Save

.dockerignore

@@ -0,0 +1,59 @@
+# .dockerignore file for the project
+
+# Language-specific patterns
+/vendor/
+*.test
+.go-cache
+
+# Development artifacts
+.idea/
+.vscode/
+*.swp
+*.swo
+dist/
+build/
+out/
+test/
+tests/
+*_test.go
+debug/
+*.log
+
+# Version control
+.git/
+.gitignore
+
+# Environment and secrets
+.env*
+*.env
+*.pem
+*.key
+*.crt
+config.local.*
+*.local.yml
+
+# Project-specific patterns
+docs/
+*.md
+README*
+Dockerfile*
+docker-compose*
+tmp/
+temp/
+*.tmp
+.local/
+local/
+
+# Exclude the following files from being ignored
+!go.mod
+!go.sum
+!cmd/main.go
+!internal/config/config.go
+!internal/domain/tasks/task.go
+!internal/domain/users/user.go
+!internal/persistance/task_manager.go
+!internal/persistance/task_repository.go
+!internal/persistance/user_repository.go
+!database/init/00-users-init.sql
+!database/init/01-tasks-init.sql
+!deployments/task-manager.yaml

Dockerfile

@@ -0,0 +1,22 @@
+# Этап сборки
+FROM golang:1.21-alpine AS builder
+
+# Устанавливаем рабочую директорию
+WORKDIR /app
+
+# Копируем файлы проекта
+COPY go.mod go.sum ./
+RUN go mod download
+
+COPY . ./
+
+# Сборка бинарного файла
+RUN go build -o /task_manager ./cmd/task_manager
+
+# Финальный минимальный образ
+FROM scratch AS final
+
+WORKDIR /app
+COPY --from=builder /task_manager .
+EXPOSE 8080
+CMD ["./task_manager"]

README.md

@@ -0,0 +1,35 @@
+# Running the Project with Docker
+
+This section provides instructions to build and run the project using Docker.
+
+## Requirements
+
+- Docker version 20.10 or later
+- Docker Compose version 1.29 or later
+
+## Environment Variables
+
+- `POSTGRES_USER`: Database username (default: `user`)
+- `POSTGRES_PASSWORD`: Database password (default: `password`)
+- `POSTGRES_DB`: Database name (default: `appdb`)
+
+## Build and Run Instructions
+
+1. Clone the repository and navigate to the project root directory.
+2. Build and start the services using Docker Compose:
+   ```bash
+   docker-compose up --build
+   ```
+3. Access the application at `http://localhost:8080`.
+
+## Configuration
+
+- The application binary is built using Go version 1.24.
+- The database service uses the `postgres:latest` image.
+
+## Exposed Ports
+
+- Application: `8080` (mapped to `8080` on the host)
+- Database: Not exposed to the host
+
+For further details, refer to the project documentation or contact the maintainers.

cmd/main.go

@@ -1,7 +0,0 @@
-package main
-
-import "fmt"
-
-func main() {
-	fmt.Println("Hello")
-}

cmd/task_manager/main.go

@@ -0,0 +1,50 @@
+package main
+
+import (
+	"database/sql"
+	"fmt"
+	"log"
+	"net/http"
+	"time"
+
+	_ "github.com/lib/pq"
+
+	"github.com/gorilla/handlers"
+	"github.com/gorilla/mux"
+
+	"task_manager/internal/app"
+	"task_manager/internal/config"
+	"task_manager/internal/persistance"
+)
+
+func main() {
+	r := mux.NewRouter()
+
+	db, err := sql.Open("postgres", config.CONNECTION_STRING)
+	if err != nil {
+		log.Fatalf("Open error database: %v", err)
+	}
+	repo := persistance.NewTaskManager(db)
+	task := app.NewTaskManager(repo)
+
+	task.RegisterRoutes(r)
+
+	corsMiddleware := handlers.CORS(
+		handlers.AllowedOrigins([]string{"*"}),
+		handlers.AllowedMethods([]string{"GET", "POST", "OPTIONS"}),
+		handlers.AllowedHeaders([]string{"Content-Type", "Authorization"}),
+	)
+
+	address := fmt.Sprintf(":%d", 8080)
+	log.Printf("The server is running on the port %s\n", address)
+	srv := &http.Server{
+		Addr:         address,
+		Handler:      corsMiddleware(r),
+		ReadTimeout:  10 * time.Second,
+		WriteTimeout: 10 * time.Second,
+		IdleTimeout:  20 * time.Second,
+	}
+	if err := srv.ListenAndServe(); err != nil {
+		log.Fatalf("Server startup error: %v", err)
+	}
+}

compose.yaml

@@ -0,0 +1,30 @@
+services:
+  app:
+    build:
+      context: .
+    ports:
+      - 8080:8080
+    restart: unless-stopped
+    depends_on:
+      - database
+  database:
+    image: postgres:latest
+    environment:
+      POSTGRES_USER: postgres
+      POSTGRES_PASSWORD: postgres
+    ports:
+      - 5432:5432
+    volumes:
+      - ./database/init:/docker-entrypoint-initdb.d
+    restart: unless-stopped
+  
+  swagger-ui:
+    image: swaggerapi/swagger-ui:latest
+    container_name: swagger-ui
+    ports:
+      - "8081:8080"
+    volumes:
+      - ./config/swagger.yaml:/tmp/swagger.yaml:ro
+    environment:
+      - SWAGGER_JSON=/tmp/swagger.yaml
+    restart: unless-stopped

config/swagger.yaml

@@ -0,0 +1,254 @@
+openapi: "3.0.0"
+info:
+  title: "Task Manager API"
+  description: "API для управления задачами, проектами и пользователями"
+  version: "1.0.0"
+
+servers:
+  - url: "http://localhost:8080/api/v1"
+    description: "Локальный сервер для тестирования API"
+
+paths:
+  /user/login:
+    post:
+      summary: "Вход пользователя в систему"
+      description: "Авторизация пользователя по имени и паролю"
+      requestBody:
+        required: true
+        content:
+          application/json:
+            schema:
+              type: object
+              properties:
+                name:
+                  type: string
+                  example: "johndoe"
+                  description: "Имя пользователя"
+                password:
+                  type: string
+                  example: "12345"
+                  description: "Пароль пользователя"
+      responses:
+        "200":
+          description: "Авторизация успешна"
+          content:
+            application/json:
+              schema:
+                type: object
+                properties:
+                  id:
+                    type: integer
+                  name:
+                    type: string
+                  email:
+                    type: string
+        "401":
+          description: "Недействительный логин или пароль"
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/ErrorResponse"
+  /user/register:
+    post:
+      summary: "Регистрация нового пользователя"
+      description: "Создание нового аккаунта пользователя"
+      requestBody:
+        required: true
+        content:
+          application/json:
+            schema:
+              $ref: "#/components/schemas/User"
+      responses:
+        "201":
+          description: "Пользователь успешно зарегистрирован"
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/User"
+        "400":
+          description: "Ошибка в запросе"
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/ErrorResponse"
+  /user/tasks:
+    get:
+      summary: "Получить задачи пользователя"
+      description: "Возвращает список задач для указанного пользователя"
+      parameters:
+        - name: "id_user"
+          in: query
+          required: true
+          schema:
+            type: integer
+            example: 1
+          description: "ID пользователя"
+      responses:
+        "200":
+          description: "Список задач пользователя"
+          content:
+            application/json:
+              schema:
+                type: array
+                items:
+                  $ref: "#/components/schemas/Task"
+        "400":
+          description: "Отсутствует ID пользователя"
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/ErrorResponse"
+  /user/projects:
+    get:
+      summary: "Получить проекты пользователя"
+      description: "Возвращает список проектов, связанных с пользователем"
+      parameters:
+        - name: "id_user"
+          in: query
+          required: true
+          schema:
+            type: integer
+            example: 1
+          description: "ID пользователя"
+      responses:
+        "200":
+          description: "Список проектов"
+          content:
+            application/json:
+              schema:
+                type: array
+                items:
+                  type: string
+        "400":
+          description: "Отсутствует ID пользователя"
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/ErrorResponse"
+  /projects:
+    post:
+      summary: "Создать проект"
+      description: "Создание нового проекта (в разработке)"
+      responses:
+        "501":
+          description: "Не реализовано"
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/UnimplementedResponse"
+    get:
+      summary: "Получить проекты"
+      description: "Получение списка всех проектов (в разработке)"
+      responses:
+        "501":
+          description: "Не реализовано"
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/UnimplementedResponse"
+  /projects/tasks:
+    post:
+      summary: "Создать задачу"
+      description: "Создание новой задачи для проекта"
+      requestBody:
+        required: true
+        content:
+          application/json:
+            schema:
+              $ref: "#/components/schemas/Task"
+      responses:
+        "201":
+          description: "Задача успешно создана"
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/Task"
+        "400":
+          description: "Ошибка в запросе"
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/ErrorResponse"
+  /projects/tasks/{task_id}:
+    patch:
+      summary: "Обновить задачу"
+      description: "Изменение данных задачи по ID"
+      parameters:
+        - name: "task_id"
+          in: path
+          required: true
+          schema:
+            type: integer
+            example: 42
+          description: "ID задачи"
+      requestBody:
+        required: true
+        content:
+          application/json:
+            schema:
+              $ref: "#/components/schemas/Task"
+      responses:
+        "200":
+          description: "Задача успешно обновлена"
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/Task"
+        "400":
+          description: "Ошибка в запросе"
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/ErrorResponse"
+  /projects/sprints:
+    post:
+      summary: "Создать спринт"
+      description: "Создание спринта в проекте (в разработке)"
+      responses:
+        "501":
+          description: "Не реализовано"
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/UnimplementedResponse"
+
+components:
+  schemas:
+    ErrorResponse:
+      type: object
+      properties:
+        code:
+          type: integer
+          description: "HTTP-код ошибки"
+        message:
+          type: string
+          description: "Сообщение об ошибке"
+        error:
+          type: string
+          description: "Машинное описание ошибки"
+    UnimplementedResponse:
+      type: object
+      properties:
+        message:
+          type: string
+          example: "Not implemented"
+    User:
+      type: object
+      properties:
+        id:
+          type: integer
+        name:
+          type: string
+        email:
+          type: string
+        password:
+          type: string
+    Task:
+      type: object
+      properties:
+        id:
+          type: integer
+        name:
+          type: string
+        description:
+          type: string

go.mod

@@ -3,6 +3,9 @@ module task_manager
 go 1.19
 
 require (
-	github.com/gorilla/mux v1.8.1 // indirect
-	github.com/lib/pq v1.10.9 // indirect
+	github.com/gorilla/handlers v1.5.2
+	github.com/gorilla/mux v1.8.1
+	github.com/lib/pq v1.10.9
 )
+
+require github.com/felixge/httpsnoop v1.0.3 // indirect

go.sum

@@ -1,3 +1,7 @@
+github.com/felixge/httpsnoop v1.0.3 h1:s/nj+GCswXYzN5v2DpNMuMQYe+0DDwt5WVCU6CWBdXk=
+github.com/felixge/httpsnoop v1.0.3/go.mod h1:m8KPJKqk1gH5J9DgRY2ASl2lWCfGKXixSwevea8zH2U=
+github.com/gorilla/handlers v1.5.2 h1:cLTUSsNkgcwhgRqvCNmdbRWG0A3N4F+M2nWKdScwyEE=
+github.com/gorilla/handlers v1.5.2/go.mod h1:dX+xVpaxdSw+q0Qek8SSsl3dfMk3jNddUkMzo0GtH0w=
 github.com/gorilla/mux v1.8.1 h1:TuBL49tXwgrFYWhqrNgrUNEY92u81SPhu7sTdzQEiWY=
 github.com/gorilla/mux v1.8.1/go.mod h1:AKf9I4AEqPTmMytcMc0KkNouC66V3BtZ4qD5fmWSiMQ=
 github.com/lib/pq v1.10.9 h1:YXG7RB+JIjhP29X+OtkiDnYaXQwpS4JEWq7dtCCRUEw=

internal/app/handlers.go

@@ -1,7 +1,13 @@
 package app
 
 import (
+	"encoding/json"
+	"errors"
 	"net/http"
+	"strconv"
+	"task_manager/internal/domain/tasks"
+	"task_manager/internal/domain/users"
+	"task_manager/internal/persistance"
 
 	gorilla "github.com/gorilla/mux"
 )
@@ -35,16 +41,174 @@ func (rm *TaskManager) RegisterRoutes(router *gorilla.Router) {
 
 }
 
-func (rm *TaskManager) handleLogin(w http.ResponseWriter, r *http.Request)               {}
-func (rm *TaskManager) handleRegistrateUser(w http.ResponseWriter, r *http.Request)      {}
-func (rm *TaskManager) handleUserTasks(w http.ResponseWriter, r *http.Request)           {}
-func (rm *TaskManager) handleUserProjects(w http.ResponseWriter, r *http.Request)        {}
-func (rm *TaskManager) handleAssignUserToProject(w http.ResponseWriter, r *http.Request) {}
+func (rm *TaskManager) handleLogin(w http.ResponseWriter, r *http.Request) {
+	var input struct {
+		Name     string `json:"name"`
+		Password string `json:"password"`
+	}
 
-func (rm *TaskManager) handleCreateProject(w http.ResponseWriter, r *http.Request)   {}
-func (rm *TaskManager) handleCreateTask(w http.ResponseWriter, r *http.Request)      {}
-func (rm *TaskManager) handleCreateSprint(w http.ResponseWriter, r *http.Request)    {}
-func (rm *TaskManager) handleGetProjectUsers(w http.ResponseWriter, r *http.Request) {}
+	err := json.NewDecoder(r.Body).Decode(&input)
+	if err != nil {
+		respondWithError(w, http.StatusBadRequest, "Invalid request payload", err)
+		return
+	}
 
-func (rm *TaskManager) handleUpdateTask(w http.ResponseWriter, r *http.Request)  {}
-func (rm *TaskManager) handleGetProjects(w http.ResponseWriter, r *http.Request) {}
+	user, err := rm.repo.GetUser(input.Name)
+	if err != nil || user.Password != persistance.GetMD5Hash(input.Password) {
+		respondWithError(w, http.StatusUnauthorized, "Invalid username or password", errors.New("authentication failed"))
+		return
+	}
+
+	respondWithJSON(w, http.StatusOK, user)
+}
+func (rm *TaskManager) handleRegistrateUser(w http.ResponseWriter, r *http.Request) {
+	var user users.User
+	err := json.NewDecoder(r.Body).Decode(&user)
+	if err != nil {
+		respondWithError(w, http.StatusBadRequest, "Invalid request payload", err)
+		return
+	}
+
+	err = rm.repo.AddUser(&user)
+	if err != nil {
+		respondWithError(w, http.StatusInternalServerError, "Failed to create user", err)
+		return
+	}
+
+	respondWithJSON(w, http.StatusCreated, user)
+}
+func (rm *TaskManager) handleUserTasks(w http.ResponseWriter, r *http.Request) {
+	userID := r.URL.Query().Get("id_user")
+	if userID == "" {
+		respondWithError(w, http.StatusBadRequest, "Missing user ID", errors.New("id_user parameter required"))
+		return
+	}
+
+	id, err := strconv.Atoi(userID)
+	if err != nil {
+		respondWithError(w, http.StatusBadRequest, "Invalid user ID", err)
+		return
+	}
+
+	tasks, err := rm.repo.GetUserTasks(id)
+	if err != nil {
+		respondWithError(w, http.StatusInternalServerError, "Failed to fetch user tasks", err)
+		return
+	}
+
+	respondWithJSON(w, http.StatusOK, tasks)
+}
+func (rm *TaskManager) handleUserProjects(w http.ResponseWriter, r *http.Request) {
+	userID := r.URL.Query().Get("id_user")
+	if userID == "" {
+		respondWithError(w, http.StatusBadRequest, "Missing user ID", errors.New("id_user parameter required"))
+		return
+	}
+
+	_, err := strconv.Atoi(userID)
+	if err != nil {
+		respondWithError(w, http.StatusBadRequest, "Invalid user ID", err)
+		return
+	}
+
+	// Заглушка: здесь предполагается метод получения проектов пользователя
+	// Для реализации необходимо будет добавить соответствующий метод в репозиторий
+	projects := []string{"Project 1", "Project 2"} // Пример данных
+
+	respondWithJSON(w, http.StatusOK, projects)
+}
+func (rm *TaskManager) handleAssignUserToProject(w http.ResponseWriter, r *http.Request) {
+	var input struct {
+		IdUser    int `json:"id_user"`
+		IdProject int `json:"id_project"`
+	}
+
+	err := json.NewDecoder(r.Body).Decode(&input)
+	if err != nil {
+		respondWithError(w, http.StatusBadRequest, "Invalid request payload", err)
+		return
+	}
+
+	// Заглушка: реализация привязки пользователя к проекту
+	// Для добавления необходимо доработать метод в репозитории
+
+	respondWithJSON(w, http.StatusOK, map[string]string{
+		"message": "User assigned to project successfully",
+	})
+}
+
+func (rm *TaskManager) handleCreateProject(w http.ResponseWriter, r *http.Request) {
+	respondWithJSON(w, http.StatusNotImplemented, map[string]string{
+		"message": "Create project not implemented yet",
+	})
+}
+func (rm *TaskManager) handleCreateTask(w http.ResponseWriter, r *http.Request) {
+	var task tasks.Task
+	err := json.NewDecoder(r.Body).Decode(&task)
+	if err != nil {
+		respondWithError(w, http.StatusBadRequest, "Invalid request payload", err)
+		return
+	}
+
+	err = rm.repo.AddTask(task)
+	if err != nil {
+		respondWithError(w, http.StatusInternalServerError, "Failed to create task", err)
+		return
+	}
+
+	respondWithJSON(w, http.StatusCreated, task)
+}
+func (rm *TaskManager) handleCreateSprint(w http.ResponseWriter, r *http.Request) {
+	taskID := gorilla.Vars(r)["task_id"]
+	id, err := strconv.Atoi(taskID)
+	if err != nil {
+		respondWithError(w, http.StatusBadRequest, "Invalid task ID", err)
+		return
+	}
+
+	var task tasks.Task
+	err = json.NewDecoder(r.Body).Decode(&task)
+	if err != nil {
+		respondWithError(w, http.StatusBadRequest, "Invalid request payload", err)
+		return
+	}
+
+	task.Id = id
+	err = rm.repo.UpdateTask(task)
+	if err != nil {
+		respondWithError(w, http.StatusInternalServerError, "Failed to update task", err)
+		return
+	}
+
+	respondWithJSON(w, http.StatusOK, task)
+}
+func (rm *TaskManager) handleGetProjectUsers(w http.ResponseWriter, r *http.Request) {
+	respondWithJSON(w, http.StatusNotImplemented, map[string]string{
+		"message": "Get projects not implemented yet",
+	})
+}
+
+func (rm *TaskManager) handleUpdateTask(w http.ResponseWriter, r *http.Request) {
+	respondWithJSON(w, http.StatusNotImplemented, map[string]string{
+		"message": "Create sprint not implemented yet",
+	})
+}
+func (rm *TaskManager) handleGetProjects(w http.ResponseWriter, r *http.Request) {
+	respondWithJSON(w, http.StatusNotImplemented, map[string]string{
+		"message": "Get project users not implemented yet",
+	})
+}
+
+func respondWithError(w http.ResponseWriter, code int, message string, err error) {
+	w.WriteHeader(code)
+	json.NewEncoder(w).Encode(ErrorResponse{
+		Code:    code,
+		Message: message,
+		Error:   err.Error(),
+	})
+}
+
+func respondWithJSON(w http.ResponseWriter, code int, payload interface{}) {
+	w.WriteHeader(code)
+	json.NewEncoder(w).Encode(payload)
+}

vendor/github.com/felixge/httpsnoop/.travis.yml

@@ -0,0 +1,6 @@
+language: go
+
+go:
+  - 1.6
+  - 1.7
+  - 1.8

vendor/github.com/felixge/httpsnoop/LICENSE.txt

@@ -0,0 +1,19 @@
+Copyright (c) 2016 Felix Geisendörfer (felix@debuggable.com)
+
+ Permission is hereby granted, free of charge, to any person obtaining a copy
+ of this software and associated documentation files (the "Software"), to deal
+ in the Software without restriction, including without limitation the rights
+ to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ copies of the Software, and to permit persons to whom the Software is
+ furnished to do so, subject to the following conditions:
+
+ The above copyright notice and this permission notice shall be included in
+ all copies or substantial portions of the Software.
+
+ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ THE SOFTWARE.

vendor/github.com/felixge/httpsnoop/Makefile

@@ -0,0 +1,10 @@
+.PHONY: ci generate clean
+
+ci: clean generate
+	go test -v ./...
+
+generate:
+	go generate .
+
+clean:
+	rm -rf *_generated*.go

vendor/github.com/felixge/httpsnoop/README.md

@@ -0,0 +1,95 @@
+# httpsnoop
+
+Package httpsnoop provides an easy way to capture http related metrics (i.e.
+response time, bytes written, and http status code) from your application's
+http.Handlers.
+
+Doing this requires non-trivial wrapping of the http.ResponseWriter interface,
+which is also exposed for users interested in a more low-level API.
+
+[![GoDoc](https://godoc.org/github.com/felixge/httpsnoop?status.svg)](https://godoc.org/github.com/felixge/httpsnoop)
+[![Build Status](https://travis-ci.org/felixge/httpsnoop.svg?branch=master)](https://travis-ci.org/felixge/httpsnoop)
+
+## Usage Example
+
+```go
+// myH is your app's http handler, perhaps a http.ServeMux or similar.
+var myH http.Handler
+// wrappedH wraps myH in order to log every request.
+wrappedH := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+	m := httpsnoop.CaptureMetrics(myH, w, r)
+	log.Printf(
+		"%s %s (code=%d dt=%s written=%d)",
+		r.Method,
+		r.URL,
+		m.Code,
+		m.Duration,
+		m.Written,
+	)
+})
+http.ListenAndServe(":8080", wrappedH)
+```
+
+## Why this package exists
+
+Instrumenting an application's http.Handler is surprisingly difficult.
+
+However if you google for e.g. "capture ResponseWriter status code" you'll find
+lots of advise and code examples that suggest it to be a fairly trivial
+undertaking. Unfortunately everything I've seen so far has a high chance of
+breaking your application.
+
+The main problem is that a `http.ResponseWriter` often implements additional
+interfaces such as `http.Flusher`, `http.CloseNotifier`, `http.Hijacker`, `http.Pusher`, and
+`io.ReaderFrom`. So the naive approach of just wrapping `http.ResponseWriter`
+in your own struct that also implements the `http.ResponseWriter` interface
+will hide the additional interfaces mentioned above. This has a high change of
+introducing subtle bugs into any non-trivial application.
+
+Another approach I've seen people take is to return a struct that implements
+all of the interfaces above. However, that's also problematic, because it's
+difficult to fake some of these interfaces behaviors when the underlying
+`http.ResponseWriter` doesn't have an implementation. It's also dangerous,
+because an application may choose to operate differently, merely because it
+detects the presence of these additional interfaces.
+
+This package solves this problem by checking which additional interfaces a
+`http.ResponseWriter` implements, returning a wrapped version implementing the
+exact same set of interfaces.
+
+Additionally this package properly handles edge cases such as `WriteHeader` not
+being called, or called more than once, as well as concurrent calls to
+`http.ResponseWriter` methods, and even calls happening after the wrapped
+`ServeHTTP` has already returned.
+
+Unfortunately this package is not perfect either. It's possible that it is
+still missing some interfaces provided by the go core (let me know if you find
+one), and it won't work for applications adding their own interfaces into the
+mix. You can however use `httpsnoop.Unwrap(w)` to access the underlying
+`http.ResponseWriter` and type-assert the result to its other interfaces.
+
+However, hopefully the explanation above has sufficiently scared you of rolling
+your own solution to this problem. httpsnoop may still break your application,
+but at least it tries to avoid it as much as possible.
+
+Anyway, the real problem here is that smuggling additional interfaces inside
+`http.ResponseWriter` is a problematic design choice, but it probably goes as
+deep as the Go language specification itself. But that's okay, I still prefer
+Go over the alternatives ;).
+
+## Performance
+
+```
+BenchmarkBaseline-8      	   20000	     94912 ns/op
+BenchmarkCaptureMetrics-8	   20000	     95461 ns/op
+```
+
+As you can see, using `CaptureMetrics` on a vanilla http.Handler introduces an
+overhead of ~500 ns per http request on my machine. However, the margin of
+error appears to be larger than that, therefor it should be reasonable to
+assume that the overhead introduced by `CaptureMetrics` is absolutely
+negligible.
+
+## License
+
+MIT

vendor/github.com/felixge/httpsnoop/capture_metrics.go

@@ -0,0 +1,86 @@
+package httpsnoop
+
+import (
+	"io"
+	"net/http"
+	"time"
+)
+
+// Metrics holds metrics captured from CaptureMetrics.
+type Metrics struct {
+	// Code is the first http response code passed to the WriteHeader func of
+	// the ResponseWriter. If no such call is made, a default code of 200 is
+	// assumed instead.
+	Code int
+	// Duration is the time it took to execute the handler.
+	Duration time.Duration
+	// Written is the number of bytes successfully written by the Write or
+	// ReadFrom function of the ResponseWriter. ResponseWriters may also write
+	// data to their underlaying connection directly (e.g. headers), but those
+	// are not tracked. Therefor the number of Written bytes will usually match
+	// the size of the response body.
+	Written int64
+}
+
+// CaptureMetrics wraps the given hnd, executes it with the given w and r, and
+// returns the metrics it captured from it.
+func CaptureMetrics(hnd http.Handler, w http.ResponseWriter, r *http.Request) Metrics {
+	return CaptureMetricsFn(w, func(ww http.ResponseWriter) {
+		hnd.ServeHTTP(ww, r)
+	})
+}
+
+// CaptureMetricsFn wraps w and calls fn with the wrapped w and returns the
+// resulting metrics. This is very similar to CaptureMetrics (which is just
+// sugar on top of this func), but is a more usable interface if your
+// application doesn't use the Go http.Handler interface.
+func CaptureMetricsFn(w http.ResponseWriter, fn func(http.ResponseWriter)) Metrics {
+	m := Metrics{Code: http.StatusOK}
+	m.CaptureMetrics(w, fn)
+	return m
+}
+
+// CaptureMetrics wraps w and calls fn with the wrapped w and updates
+// Metrics m with the resulting metrics. This is similar to CaptureMetricsFn,
+// but allows one to customize starting Metrics object.
+func (m *Metrics) CaptureMetrics(w http.ResponseWriter, fn func(http.ResponseWriter)) {
+	var (
+		start         = time.Now()
+		headerWritten bool
+		hooks         = Hooks{
+			WriteHeader: func(next WriteHeaderFunc) WriteHeaderFunc {
+				return func(code int) {
+					next(code)
+
+					if !headerWritten {
+						m.Code = code
+						headerWritten = true
+					}
+				}
+			},
+
+			Write: func(next WriteFunc) WriteFunc {
+				return func(p []byte) (int, error) {
+					n, err := next(p)
+
+					m.Written += int64(n)
+					headerWritten = true
+					return n, err
+				}
+			},
+
+			ReadFrom: func(next ReadFromFunc) ReadFromFunc {
+				return func(src io.Reader) (int64, error) {
+					n, err := next(src)
+
+					headerWritten = true
+					m.Written += n
+					return n, err
+				}
+			},
+		}
+	)
+
+	fn(Wrap(w, hooks))
+	m.Duration += time.Since(start)
+}

vendor/github.com/felixge/httpsnoop/docs.go

@@ -0,0 +1,10 @@
+// Package httpsnoop provides an easy way to capture http related metrics (i.e.
+// response time, bytes written, and http status code) from your application's
+// http.Handlers.
+//
+// Doing this requires non-trivial wrapping of the http.ResponseWriter
+// interface, which is also exposed for users interested in a more low-level
+// API.
+package httpsnoop
+
+//go:generate go run codegen/main.go

vendor/github.com/felixge/httpsnoop/wrap_generated_gteq_1.8.go

@@ -0,0 +1,436 @@
+// +build go1.8
+// Code generated by "httpsnoop/codegen"; DO NOT EDIT
+
+package httpsnoop
+
+import (
+	"bufio"
+	"io"
+	"net"
+	"net/http"
+)
+
+// HeaderFunc is part of the http.ResponseWriter interface.
+type HeaderFunc func() http.Header
+
+// WriteHeaderFunc is part of the http.ResponseWriter interface.
+type WriteHeaderFunc func(code int)
+
+// WriteFunc is part of the http.ResponseWriter interface.
+type WriteFunc func(b []byte) (int, error)
+
+// FlushFunc is part of the http.Flusher interface.
+type FlushFunc func()
+
+// CloseNotifyFunc is part of the http.CloseNotifier interface.
+type CloseNotifyFunc func() <-chan bool
+
+// HijackFunc is part of the http.Hijacker interface.
+type HijackFunc func() (net.Conn, *bufio.ReadWriter, error)
+
+// ReadFromFunc is part of the io.ReaderFrom interface.
+type ReadFromFunc func(src io.Reader) (int64, error)
+
+// PushFunc is part of the http.Pusher interface.
+type PushFunc func(target string, opts *http.PushOptions) error
+
+// Hooks defines a set of method interceptors for methods included in
+// http.ResponseWriter as well as some others. You can think of them as
+// middleware for the function calls they target. See Wrap for more details.
+type Hooks struct {
+	Header      func(HeaderFunc) HeaderFunc
+	WriteHeader func(WriteHeaderFunc) WriteHeaderFunc
+	Write       func(WriteFunc) WriteFunc
+	Flush       func(FlushFunc) FlushFunc
+	CloseNotify func(CloseNotifyFunc) CloseNotifyFunc
+	Hijack      func(HijackFunc) HijackFunc
+	ReadFrom    func(ReadFromFunc) ReadFromFunc
+	Push        func(PushFunc) PushFunc
+}
+
+// Wrap returns a wrapped version of w that provides the exact same interface
+// as w. Specifically if w implements any combination of:
+//
+// - http.Flusher
+// - http.CloseNotifier
+// - http.Hijacker
+// - io.ReaderFrom
+// - http.Pusher
+//
+// The wrapped version will implement the exact same combination. If no hooks
+// are set, the wrapped version also behaves exactly as w. Hooks targeting
+// methods not supported by w are ignored. Any other hooks will intercept the
+// method they target and may modify the call's arguments and/or return values.
+// The CaptureMetrics implementation serves as a working example for how the
+// hooks can be used.
+func Wrap(w http.ResponseWriter, hooks Hooks) http.ResponseWriter {
+	rw := &rw{w: w, h: hooks}
+	_, i0 := w.(http.Flusher)
+	_, i1 := w.(http.CloseNotifier)
+	_, i2 := w.(http.Hijacker)
+	_, i3 := w.(io.ReaderFrom)
+	_, i4 := w.(http.Pusher)
+	switch {
+	// combination 1/32
+	case !i0 && !i1 && !i2 && !i3 && !i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+		}{rw, rw}
+	// combination 2/32
+	case !i0 && !i1 && !i2 && !i3 && i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Pusher
+		}{rw, rw, rw}
+	// combination 3/32
+	case !i0 && !i1 && !i2 && i3 && !i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			io.ReaderFrom
+		}{rw, rw, rw}
+	// combination 4/32
+	case !i0 && !i1 && !i2 && i3 && i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			io.ReaderFrom
+			http.Pusher
+		}{rw, rw, rw, rw}
+	// combination 5/32
+	case !i0 && !i1 && i2 && !i3 && !i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Hijacker
+		}{rw, rw, rw}
+	// combination 6/32
+	case !i0 && !i1 && i2 && !i3 && i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Hijacker
+			http.Pusher
+		}{rw, rw, rw, rw}
+	// combination 7/32
+	case !i0 && !i1 && i2 && i3 && !i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Hijacker
+			io.ReaderFrom
+		}{rw, rw, rw, rw}
+	// combination 8/32
+	case !i0 && !i1 && i2 && i3 && i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Hijacker
+			io.ReaderFrom
+			http.Pusher
+		}{rw, rw, rw, rw, rw}
+	// combination 9/32
+	case !i0 && i1 && !i2 && !i3 && !i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.CloseNotifier
+		}{rw, rw, rw}
+	// combination 10/32
+	case !i0 && i1 && !i2 && !i3 && i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.CloseNotifier
+			http.Pusher
+		}{rw, rw, rw, rw}
+	// combination 11/32
+	case !i0 && i1 && !i2 && i3 && !i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.CloseNotifier
+			io.ReaderFrom
+		}{rw, rw, rw, rw}
+	// combination 12/32
+	case !i0 && i1 && !i2 && i3 && i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.CloseNotifier
+			io.ReaderFrom
+			http.Pusher
+		}{rw, rw, rw, rw, rw}
+	// combination 13/32
+	case !i0 && i1 && i2 && !i3 && !i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.CloseNotifier
+			http.Hijacker
+		}{rw, rw, rw, rw}
+	// combination 14/32
+	case !i0 && i1 && i2 && !i3 && i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.CloseNotifier
+			http.Hijacker
+			http.Pusher
+		}{rw, rw, rw, rw, rw}
+	// combination 15/32
+	case !i0 && i1 && i2 && i3 && !i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.CloseNotifier
+			http.Hijacker
+			io.ReaderFrom
+		}{rw, rw, rw, rw, rw}
+	// combination 16/32
+	case !i0 && i1 && i2 && i3 && i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.CloseNotifier
+			http.Hijacker
+			io.ReaderFrom
+			http.Pusher
+		}{rw, rw, rw, rw, rw, rw}
+	// combination 17/32
+	case i0 && !i1 && !i2 && !i3 && !i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+		}{rw, rw, rw}
+	// combination 18/32
+	case i0 && !i1 && !i2 && !i3 && i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.Pusher
+		}{rw, rw, rw, rw}
+	// combination 19/32
+	case i0 && !i1 && !i2 && i3 && !i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			io.ReaderFrom
+		}{rw, rw, rw, rw}
+	// combination 20/32
+	case i0 && !i1 && !i2 && i3 && i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			io.ReaderFrom
+			http.Pusher
+		}{rw, rw, rw, rw, rw}
+	// combination 21/32
+	case i0 && !i1 && i2 && !i3 && !i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.Hijacker
+		}{rw, rw, rw, rw}
+	// combination 22/32
+	case i0 && !i1 && i2 && !i3 && i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.Hijacker
+			http.Pusher
+		}{rw, rw, rw, rw, rw}
+	// combination 23/32
+	case i0 && !i1 && i2 && i3 && !i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.Hijacker
+			io.ReaderFrom
+		}{rw, rw, rw, rw, rw}
+	// combination 24/32
+	case i0 && !i1 && i2 && i3 && i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.Hijacker
+			io.ReaderFrom
+			http.Pusher
+		}{rw, rw, rw, rw, rw, rw}
+	// combination 25/32
+	case i0 && i1 && !i2 && !i3 && !i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+		}{rw, rw, rw, rw}
+	// combination 26/32
+	case i0 && i1 && !i2 && !i3 && i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+			http.Pusher
+		}{rw, rw, rw, rw, rw}
+	// combination 27/32
+	case i0 && i1 && !i2 && i3 && !i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+			io.ReaderFrom
+		}{rw, rw, rw, rw, rw}
+	// combination 28/32
+	case i0 && i1 && !i2 && i3 && i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+			io.ReaderFrom
+			http.Pusher
+		}{rw, rw, rw, rw, rw, rw}
+	// combination 29/32
+	case i0 && i1 && i2 && !i3 && !i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+			http.Hijacker
+		}{rw, rw, rw, rw, rw}
+	// combination 30/32
+	case i0 && i1 && i2 && !i3 && i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+			http.Hijacker
+			http.Pusher
+		}{rw, rw, rw, rw, rw, rw}
+	// combination 31/32
+	case i0 && i1 && i2 && i3 && !i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+			http.Hijacker
+			io.ReaderFrom
+		}{rw, rw, rw, rw, rw, rw}
+	// combination 32/32
+	case i0 && i1 && i2 && i3 && i4:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+			http.Hijacker
+			io.ReaderFrom
+			http.Pusher
+		}{rw, rw, rw, rw, rw, rw, rw}
+	}
+	panic("unreachable")
+}
+
+type rw struct {
+	w http.ResponseWriter
+	h Hooks
+}
+
+func (w *rw) Unwrap() http.ResponseWriter {
+	return w.w
+}
+
+func (w *rw) Header() http.Header {
+	f := w.w.(http.ResponseWriter).Header
+	if w.h.Header != nil {
+		f = w.h.Header(f)
+	}
+	return f()
+}
+
+func (w *rw) WriteHeader(code int) {
+	f := w.w.(http.ResponseWriter).WriteHeader
+	if w.h.WriteHeader != nil {
+		f = w.h.WriteHeader(f)
+	}
+	f(code)
+}
+
+func (w *rw) Write(b []byte) (int, error) {
+	f := w.w.(http.ResponseWriter).Write
+	if w.h.Write != nil {
+		f = w.h.Write(f)
+	}
+	return f(b)
+}
+
+func (w *rw) Flush() {
+	f := w.w.(http.Flusher).Flush
+	if w.h.Flush != nil {
+		f = w.h.Flush(f)
+	}
+	f()
+}
+
+func (w *rw) CloseNotify() <-chan bool {
+	f := w.w.(http.CloseNotifier).CloseNotify
+	if w.h.CloseNotify != nil {
+		f = w.h.CloseNotify(f)
+	}
+	return f()
+}
+
+func (w *rw) Hijack() (net.Conn, *bufio.ReadWriter, error) {
+	f := w.w.(http.Hijacker).Hijack
+	if w.h.Hijack != nil {
+		f = w.h.Hijack(f)
+	}
+	return f()
+}
+
+func (w *rw) ReadFrom(src io.Reader) (int64, error) {
+	f := w.w.(io.ReaderFrom).ReadFrom
+	if w.h.ReadFrom != nil {
+		f = w.h.ReadFrom(f)
+	}
+	return f(src)
+}
+
+func (w *rw) Push(target string, opts *http.PushOptions) error {
+	f := w.w.(http.Pusher).Push
+	if w.h.Push != nil {
+		f = w.h.Push(f)
+	}
+	return f(target, opts)
+}
+
+type Unwrapper interface {
+	Unwrap() http.ResponseWriter
+}
+
+// Unwrap returns the underlying http.ResponseWriter from within zero or more
+// layers of httpsnoop wrappers.
+func Unwrap(w http.ResponseWriter) http.ResponseWriter {
+	if rw, ok := w.(Unwrapper); ok {
+		// recurse until rw.Unwrap() returns a non-Unwrapper
+		return Unwrap(rw.Unwrap())
+	} else {
+		return w
+	}
+}

vendor/github.com/felixge/httpsnoop/wrap_generated_lt_1.8.go

@@ -0,0 +1,278 @@
+// +build !go1.8
+// Code generated by "httpsnoop/codegen"; DO NOT EDIT
+
+package httpsnoop
+
+import (
+	"bufio"
+	"io"
+	"net"
+	"net/http"
+)
+
+// HeaderFunc is part of the http.ResponseWriter interface.
+type HeaderFunc func() http.Header
+
+// WriteHeaderFunc is part of the http.ResponseWriter interface.
+type WriteHeaderFunc func(code int)
+
+// WriteFunc is part of the http.ResponseWriter interface.
+type WriteFunc func(b []byte) (int, error)
+
+// FlushFunc is part of the http.Flusher interface.
+type FlushFunc func()
+
+// CloseNotifyFunc is part of the http.CloseNotifier interface.
+type CloseNotifyFunc func() <-chan bool
+
+// HijackFunc is part of the http.Hijacker interface.
+type HijackFunc func() (net.Conn, *bufio.ReadWriter, error)
+
+// ReadFromFunc is part of the io.ReaderFrom interface.
+type ReadFromFunc func(src io.Reader) (int64, error)
+
+// Hooks defines a set of method interceptors for methods included in
+// http.ResponseWriter as well as some others. You can think of them as
+// middleware for the function calls they target. See Wrap for more details.
+type Hooks struct {
+	Header      func(HeaderFunc) HeaderFunc
+	WriteHeader func(WriteHeaderFunc) WriteHeaderFunc
+	Write       func(WriteFunc) WriteFunc
+	Flush       func(FlushFunc) FlushFunc
+	CloseNotify func(CloseNotifyFunc) CloseNotifyFunc
+	Hijack      func(HijackFunc) HijackFunc
+	ReadFrom    func(ReadFromFunc) ReadFromFunc
+}
+
+// Wrap returns a wrapped version of w that provides the exact same interface
+// as w. Specifically if w implements any combination of:
+//
+// - http.Flusher
+// - http.CloseNotifier
+// - http.Hijacker
+// - io.ReaderFrom
+//
+// The wrapped version will implement the exact same combination. If no hooks
+// are set, the wrapped version also behaves exactly as w. Hooks targeting
+// methods not supported by w are ignored. Any other hooks will intercept the
+// method they target and may modify the call's arguments and/or return values.
+// The CaptureMetrics implementation serves as a working example for how the
+// hooks can be used.
+func Wrap(w http.ResponseWriter, hooks Hooks) http.ResponseWriter {
+	rw := &rw{w: w, h: hooks}
+	_, i0 := w.(http.Flusher)
+	_, i1 := w.(http.CloseNotifier)
+	_, i2 := w.(http.Hijacker)
+	_, i3 := w.(io.ReaderFrom)
+	switch {
+	// combination 1/16
+	case !i0 && !i1 && !i2 && !i3:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+		}{rw, rw}
+	// combination 2/16
+	case !i0 && !i1 && !i2 && i3:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			io.ReaderFrom
+		}{rw, rw, rw}
+	// combination 3/16
+	case !i0 && !i1 && i2 && !i3:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Hijacker
+		}{rw, rw, rw}
+	// combination 4/16
+	case !i0 && !i1 && i2 && i3:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Hijacker
+			io.ReaderFrom
+		}{rw, rw, rw, rw}
+	// combination 5/16
+	case !i0 && i1 && !i2 && !i3:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.CloseNotifier
+		}{rw, rw, rw}
+	// combination 6/16
+	case !i0 && i1 && !i2 && i3:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.CloseNotifier
+			io.ReaderFrom
+		}{rw, rw, rw, rw}
+	// combination 7/16
+	case !i0 && i1 && i2 && !i3:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.CloseNotifier
+			http.Hijacker
+		}{rw, rw, rw, rw}
+	// combination 8/16
+	case !i0 && i1 && i2 && i3:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.CloseNotifier
+			http.Hijacker
+			io.ReaderFrom
+		}{rw, rw, rw, rw, rw}
+	// combination 9/16
+	case i0 && !i1 && !i2 && !i3:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+		}{rw, rw, rw}
+	// combination 10/16
+	case i0 && !i1 && !i2 && i3:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			io.ReaderFrom
+		}{rw, rw, rw, rw}
+	// combination 11/16
+	case i0 && !i1 && i2 && !i3:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.Hijacker
+		}{rw, rw, rw, rw}
+	// combination 12/16
+	case i0 && !i1 && i2 && i3:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.Hijacker
+			io.ReaderFrom
+		}{rw, rw, rw, rw, rw}
+	// combination 13/16
+	case i0 && i1 && !i2 && !i3:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+		}{rw, rw, rw, rw}
+	// combination 14/16
+	case i0 && i1 && !i2 && i3:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+			io.ReaderFrom
+		}{rw, rw, rw, rw, rw}
+	// combination 15/16
+	case i0 && i1 && i2 && !i3:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+			http.Hijacker
+		}{rw, rw, rw, rw, rw}
+	// combination 16/16
+	case i0 && i1 && i2 && i3:
+		return struct {
+			Unwrapper
+			http.ResponseWriter
+			http.Flusher
+			http.CloseNotifier
+			http.Hijacker
+			io.ReaderFrom
+		}{rw, rw, rw, rw, rw, rw}
+	}
+	panic("unreachable")
+}
+
+type rw struct {
+	w http.ResponseWriter
+	h Hooks
+}
+
+func (w *rw) Unwrap() http.ResponseWriter {
+	return w.w
+}
+
+func (w *rw) Header() http.Header {
+	f := w.w.(http.ResponseWriter).Header
+	if w.h.Header != nil {
+		f = w.h.Header(f)
+	}
+	return f()
+}
+
+func (w *rw) WriteHeader(code int) {
+	f := w.w.(http.ResponseWriter).WriteHeader
+	if w.h.WriteHeader != nil {
+		f = w.h.WriteHeader(f)
+	}
+	f(code)
+}
+
+func (w *rw) Write(b []byte) (int, error) {
+	f := w.w.(http.ResponseWriter).Write
+	if w.h.Write != nil {
+		f = w.h.Write(f)
+	}
+	return f(b)
+}
+
+func (w *rw) Flush() {
+	f := w.w.(http.Flusher).Flush
+	if w.h.Flush != nil {
+		f = w.h.Flush(f)
+	}
+	f()
+}
+
+func (w *rw) CloseNotify() <-chan bool {
+	f := w.w.(http.CloseNotifier).CloseNotify
+	if w.h.CloseNotify != nil {
+		f = w.h.CloseNotify(f)
+	}
+	return f()
+}
+
+func (w *rw) Hijack() (net.Conn, *bufio.ReadWriter, error) {
+	f := w.w.(http.Hijacker).Hijack
+	if w.h.Hijack != nil {
+		f = w.h.Hijack(f)
+	}
+	return f()
+}
+
+func (w *rw) ReadFrom(src io.Reader) (int64, error) {
+	f := w.w.(io.ReaderFrom).ReadFrom
+	if w.h.ReadFrom != nil {
+		f = w.h.ReadFrom(f)
+	}
+	return f(src)
+}
+
+type Unwrapper interface {
+	Unwrap() http.ResponseWriter
+}
+
+// Unwrap returns the underlying http.ResponseWriter from within zero or more
+// layers of httpsnoop wrappers.
+func Unwrap(w http.ResponseWriter) http.ResponseWriter {
+	if rw, ok := w.(Unwrapper); ok {
+		// recurse until rw.Unwrap() returns a non-Unwrapper
+		return Unwrap(rw.Unwrap())
+	} else {
+		return w
+	}
+}

vendor/github.com/gorilla/handlers/.editorconfig

@@ -0,0 +1,20 @@
+; https://editorconfig.org/
+
+root = true
+
+[*]
+insert_final_newline = true
+charset = utf-8
+trim_trailing_whitespace = true
+indent_style = space
+indent_size = 2
+
+[{Makefile,go.mod,go.sum,*.go,.gitmodules}]
+indent_style = tab
+indent_size = 4
+
+[*.md]
+indent_size = 4
+trim_trailing_whitespace = false
+
+eclint_indent_style = unset

vendor/github.com/gorilla/handlers/.gitignore

@@ -0,0 +1,2 @@
+# Output of the go test coverage tool
+coverage.coverprofile

vendor/github.com/gorilla/handlers/LICENSE

@@ -0,0 +1,27 @@
+Copyright (c) 2023 The Gorilla Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+	 * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+	 * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+	 * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

vendor/github.com/gorilla/handlers/Makefile

@@ -0,0 +1,34 @@
+GO_LINT=$(shell which golangci-lint 2> /dev/null || echo '')
+GO_LINT_URI=github.com/golangci/golangci-lint/cmd/golangci-lint@latest
+
+GO_SEC=$(shell which gosec 2> /dev/null || echo '')
+GO_SEC_URI=github.com/securego/gosec/v2/cmd/gosec@latest
+
+GO_VULNCHECK=$(shell which govulncheck 2> /dev/null || echo '')
+GO_VULNCHECK_URI=golang.org/x/vuln/cmd/govulncheck@latest
+
+.PHONY: verify
+verify: sec govulncheck lint test
+
+.PHONY: lint
+lint:
+	$(if $(GO_LINT), ,go install $(GO_LINT_URI))
+	@echo "##### Running golangci-lint #####"
+	golangci-lint run -v
+
+.PHONY: sec
+sec:
+	$(if $(GO_SEC), ,go install $(GO_SEC_URI))
+	@echo "##### Running gosec #####"
+	gosec ./...
+
+.PHONY: govulncheck
+govulncheck:
+	$(if $(GO_VULNCHECK), ,go install $(GO_VULNCHECK_URI))
+	@echo "##### Running govulncheck #####"
+	govulncheck ./...
+
+.PHONY: test
+test:
+	@echo "##### Running tests #####"
+	go test -race -cover -coverprofile=coverage.coverprofile -covermode=atomic -v ./...

vendor/github.com/gorilla/handlers/README.md

@@ -0,0 +1,56 @@
+# gorilla/handlers
+
+![Testing](https://github.com/gorilla/handlers/actions/workflows/test.yml/badge.svg)
+[![Codecov](https://codecov.io/github/gorilla/handlers/branch/main/graph/badge.svg)](https://codecov.io/github/gorilla/handlers)
+[![GoDoc](https://godoc.org/github.com/gorilla/handlers?status.svg)](https://godoc.org/github.com/gorilla/handlers)
+[![Sourcegraph](https://sourcegraph.com/github.com/gorilla/handlers/-/badge.svg)](https://sourcegraph.com/github.com/gorilla/handlers?badge)
+
+Package handlers is a collection of handlers (aka "HTTP middleware") for use
+with Go's `net/http` package (or any framework supporting `http.Handler`), including:
+
+* [**LoggingHandler**](https://godoc.org/github.com/gorilla/handlers#LoggingHandler) for logging HTTP requests in the Apache [Common Log
+  Format](http://httpd.apache.org/docs/2.2/logs.html#common).
+* [**CombinedLoggingHandler**](https://godoc.org/github.com/gorilla/handlers#CombinedLoggingHandler) for logging HTTP requests in the Apache [Combined Log
+  Format](http://httpd.apache.org/docs/2.2/logs.html#combined) commonly used by
+  both Apache and nginx.
+* [**CompressHandler**](https://godoc.org/github.com/gorilla/handlers#CompressHandler) for gzipping responses.
+* [**ContentTypeHandler**](https://godoc.org/github.com/gorilla/handlers#ContentTypeHandler) for validating requests against a list of accepted
+  content types.
+* [**MethodHandler**](https://godoc.org/github.com/gorilla/handlers#MethodHandler) for matching HTTP methods against handlers in a
+  `map[string]http.Handler`
+* [**ProxyHeaders**](https://godoc.org/github.com/gorilla/handlers#ProxyHeaders) for populating `r.RemoteAddr` and `r.URL.Scheme` based on the
+  `X-Forwarded-For`, `X-Real-IP`, `X-Forwarded-Proto` and RFC7239 `Forwarded`
+  headers when running a Go server behind a HTTP reverse proxy.
+* [**CanonicalHost**](https://godoc.org/github.com/gorilla/handlers#CanonicalHost) for re-directing to the preferred host when handling multiple 
+  domains (i.e. multiple CNAME aliases).
+* [**RecoveryHandler**](https://godoc.org/github.com/gorilla/handlers#RecoveryHandler) for recovering from unexpected panics.
+
+Other handlers are documented [on the Gorilla
+website](https://www.gorillatoolkit.org/pkg/handlers).
+
+## Example
+
+A simple example using `handlers.LoggingHandler` and `handlers.CompressHandler`:
+
+```go
+import (
+    "net/http"
+    "github.com/gorilla/handlers"
+)
+
+func main() {
+    r := http.NewServeMux()
+
+    // Only log requests to our admin dashboard to stdout
+    r.Handle("/admin", handlers.LoggingHandler(os.Stdout, http.HandlerFunc(ShowAdminDashboard)))
+    r.HandleFunc("/", ShowIndex)
+
+    // Wrap our server with our gzip handler to gzip compress all responses.
+    http.ListenAndServe(":8000", handlers.CompressHandler(r))
+}
+```
+
+## License
+
+BSD licensed. See the included LICENSE file for details.
+

vendor/github.com/gorilla/handlers/canonical.go

@@ -0,0 +1,73 @@
+package handlers
+
+import (
+	"net/http"
+	"net/url"
+	"strings"
+)
+
+type canonical struct {
+	h      http.Handler
+	domain string
+	code   int
+}
+
+// CanonicalHost is HTTP middleware that re-directs requests to the canonical
+// domain. It accepts a domain and a status code (e.g. 301 or 302) and
+// re-directs clients to this domain. The existing request path is maintained.
+//
+// Note: If the provided domain is considered invalid by url.Parse or otherwise
+// returns an empty scheme or host, clients are not re-directed.
+//
+// Example:
+//
+//	r := mux.NewRouter()
+//	canonical := handlers.CanonicalHost("http://www.gorillatoolkit.org", 302)
+//	r.HandleFunc("/route", YourHandler)
+//
+//	log.Fatal(http.ListenAndServe(":7000", canonical(r)))
+func CanonicalHost(domain string, code int) func(h http.Handler) http.Handler {
+	fn := func(h http.Handler) http.Handler {
+		return canonical{h, domain, code}
+	}
+
+	return fn
+}
+
+func (c canonical) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	dest, err := url.Parse(c.domain)
+	if err != nil {
+		// Call the next handler if the provided domain fails to parse.
+		c.h.ServeHTTP(w, r)
+		return
+	}
+
+	if dest.Scheme == "" || dest.Host == "" {
+		// Call the next handler if the scheme or host are empty.
+		// Note that url.Parse won't fail on in this case.
+		c.h.ServeHTTP(w, r)
+		return
+	}
+
+	if !strings.EqualFold(cleanHost(r.Host), dest.Host) {
+		// Re-build the destination URL
+		dest := dest.Scheme + "://" + dest.Host + r.URL.Path
+		if r.URL.RawQuery != "" {
+			dest += "?" + r.URL.RawQuery
+		}
+		http.Redirect(w, r, dest, c.code)
+		return
+	}
+
+	c.h.ServeHTTP(w, r)
+}
+
+// cleanHost cleans invalid Host headers by stripping anything after '/' or ' '.
+// This is backported from Go 1.5 (in response to issue #11206) and attempts to
+// mitigate malformed Host headers that do not match the format in RFC7230.
+func cleanHost(in string) string {
+	if i := strings.IndexAny(in, " /"); i != -1 {
+		return in[:i]
+	}
+	return in
+}

vendor/github.com/gorilla/handlers/compress.go

@@ -0,0 +1,143 @@
+// Copyright 2013 The Gorilla Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package handlers
+
+import (
+	"compress/flate"
+	"compress/gzip"
+	"io"
+	"net/http"
+	"strings"
+
+	"github.com/felixge/httpsnoop"
+)
+
+const acceptEncoding string = "Accept-Encoding"
+
+type compressResponseWriter struct {
+	compressor io.Writer
+	w          http.ResponseWriter
+}
+
+func (cw *compressResponseWriter) WriteHeader(c int) {
+	cw.w.Header().Del("Content-Length")
+	cw.w.WriteHeader(c)
+}
+
+func (cw *compressResponseWriter) Write(b []byte) (int, error) {
+	h := cw.w.Header()
+	if h.Get("Content-Type") == "" {
+		h.Set("Content-Type", http.DetectContentType(b))
+	}
+	h.Del("Content-Length")
+
+	return cw.compressor.Write(b)
+}
+
+func (cw *compressResponseWriter) ReadFrom(r io.Reader) (int64, error) {
+	return io.Copy(cw.compressor, r)
+}
+
+type flusher interface {
+	Flush() error
+}
+
+func (cw *compressResponseWriter) Flush() {
+	// Flush compressed data if compressor supports it.
+	if f, ok := cw.compressor.(flusher); ok {
+		_ = f.Flush()
+	}
+	// Flush HTTP response.
+	if f, ok := cw.w.(http.Flusher); ok {
+		f.Flush()
+	}
+}
+
+// CompressHandler gzip compresses HTTP responses for clients that support it
+// via the 'Accept-Encoding' header.
+//
+// Compressing TLS traffic may leak the page contents to an attacker if the
+// page contains user input: http://security.stackexchange.com/a/102015/12208
+func CompressHandler(h http.Handler) http.Handler {
+	return CompressHandlerLevel(h, gzip.DefaultCompression)
+}
+
+// CompressHandlerLevel gzip compresses HTTP responses with specified compression level
+// for clients that support it via the 'Accept-Encoding' header.
+//
+// The compression level should be gzip.DefaultCompression, gzip.NoCompression,
+// or any integer value between gzip.BestSpeed and gzip.BestCompression inclusive.
+// gzip.DefaultCompression is used in case of invalid compression level.
+func CompressHandlerLevel(h http.Handler, level int) http.Handler {
+	if level < gzip.DefaultCompression || level > gzip.BestCompression {
+		level = gzip.DefaultCompression
+	}
+
+	const (
+		gzipEncoding  = "gzip"
+		flateEncoding = "deflate"
+	)
+
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		// detect what encoding to use
+		var encoding string
+		for _, curEnc := range strings.Split(r.Header.Get(acceptEncoding), ",") {
+			curEnc = strings.TrimSpace(curEnc)
+			if curEnc == gzipEncoding || curEnc == flateEncoding {
+				encoding = curEnc
+				break
+			}
+		}
+
+		// always add Accept-Encoding to Vary to prevent intermediate caches corruption
+		w.Header().Add("Vary", acceptEncoding)
+
+		// if we weren't able to identify an encoding we're familiar with, pass on the
+		// request to the handler and return
+		if encoding == "" {
+			h.ServeHTTP(w, r)
+			return
+		}
+
+		if r.Header.Get("Upgrade") != "" {
+			h.ServeHTTP(w, r)
+			return
+		}
+
+		// wrap the ResponseWriter with the writer for the chosen encoding
+		var encWriter io.WriteCloser
+		if encoding == gzipEncoding {
+			encWriter, _ = gzip.NewWriterLevel(w, level)
+		} else if encoding == flateEncoding {
+			encWriter, _ = flate.NewWriter(w, level)
+		}
+		defer encWriter.Close()
+
+		w.Header().Set("Content-Encoding", encoding)
+		r.Header.Del(acceptEncoding)
+
+		cw := &compressResponseWriter{
+			w:          w,
+			compressor: encWriter,
+		}
+
+		w = httpsnoop.Wrap(w, httpsnoop.Hooks{
+			Write: func(httpsnoop.WriteFunc) httpsnoop.WriteFunc {
+				return cw.Write
+			},
+			WriteHeader: func(httpsnoop.WriteHeaderFunc) httpsnoop.WriteHeaderFunc {
+				return cw.WriteHeader
+			},
+			Flush: func(httpsnoop.FlushFunc) httpsnoop.FlushFunc {
+				return cw.Flush
+			},
+			ReadFrom: func(rff httpsnoop.ReadFromFunc) httpsnoop.ReadFromFunc {
+				return cw.ReadFrom
+			},
+		})
+
+		h.ServeHTTP(w, r)
+	})
+}

vendor/github.com/gorilla/handlers/cors.go

@@ -0,0 +1,352 @@
+package handlers
+
+import (
+	"net/http"
+	"strconv"
+	"strings"
+)
+
+// CORSOption represents a functional option for configuring the CORS middleware.
+type CORSOption func(*cors) error
+
+type cors struct {
+	h                      http.Handler
+	allowedHeaders         []string
+	allowedMethods         []string
+	allowedOrigins         []string
+	allowedOriginValidator OriginValidator
+	exposedHeaders         []string
+	maxAge                 int
+	ignoreOptions          bool
+	allowCredentials       bool
+	optionStatusCode       int
+}
+
+// OriginValidator takes an origin string and returns whether or not that origin is allowed.
+type OriginValidator func(string) bool
+
+var (
+	defaultCorsOptionStatusCode = http.StatusOK
+	defaultCorsMethods          = []string{http.MethodGet, http.MethodHead, http.MethodPost}
+	defaultCorsHeaders          = []string{"Accept", "Accept-Language", "Content-Language", "Origin"}
+	// (WebKit/Safari v9 sends the Origin header by default in AJAX requests).
+)
+
+const (
+	corsOptionMethod           string = http.MethodOptions
+	corsAllowOriginHeader      string = "Access-Control-Allow-Origin"
+	corsExposeHeadersHeader    string = "Access-Control-Expose-Headers"
+	corsMaxAgeHeader           string = "Access-Control-Max-Age"
+	corsAllowMethodsHeader     string = "Access-Control-Allow-Methods"
+	corsAllowHeadersHeader     string = "Access-Control-Allow-Headers"
+	corsAllowCredentialsHeader string = "Access-Control-Allow-Credentials"
+	corsRequestMethodHeader    string = "Access-Control-Request-Method"
+	corsRequestHeadersHeader   string = "Access-Control-Request-Headers"
+	corsOriginHeader           string = "Origin"
+	corsVaryHeader             string = "Vary"
+	corsOriginMatchAll         string = "*"
+)
+
+func (ch *cors) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	origin := r.Header.Get(corsOriginHeader)
+	if !ch.isOriginAllowed(origin) {
+		if r.Method != corsOptionMethod || ch.ignoreOptions {
+			ch.h.ServeHTTP(w, r)
+		}
+
+		return
+	}
+
+	if r.Method == corsOptionMethod {
+		if ch.ignoreOptions {
+			ch.h.ServeHTTP(w, r)
+			return
+		}
+
+		if _, ok := r.Header[corsRequestMethodHeader]; !ok {
+			w.WriteHeader(http.StatusBadRequest)
+			return
+		}
+
+		method := r.Header.Get(corsRequestMethodHeader)
+		if !ch.isMatch(method, ch.allowedMethods) {
+			w.WriteHeader(http.StatusMethodNotAllowed)
+			return
+		}
+
+		requestHeaders := strings.Split(r.Header.Get(corsRequestHeadersHeader), ",")
+		allowedHeaders := []string{}
+		for _, v := range requestHeaders {
+			canonicalHeader := http.CanonicalHeaderKey(strings.TrimSpace(v))
+			if canonicalHeader == "" || ch.isMatch(canonicalHeader, defaultCorsHeaders) {
+				continue
+			}
+
+			if !ch.isMatch(canonicalHeader, ch.allowedHeaders) {
+				w.WriteHeader(http.StatusForbidden)
+				return
+			}
+
+			allowedHeaders = append(allowedHeaders, canonicalHeader)
+		}
+
+		if len(allowedHeaders) > 0 {
+			w.Header().Set(corsAllowHeadersHeader, strings.Join(allowedHeaders, ","))
+		}
+
+		if ch.maxAge > 0 {
+			w.Header().Set(corsMaxAgeHeader, strconv.Itoa(ch.maxAge))
+		}
+
+		if !ch.isMatch(method, defaultCorsMethods) {
+			w.Header().Set(corsAllowMethodsHeader, method)
+		}
+	} else if len(ch.exposedHeaders) > 0 {
+		w.Header().Set(corsExposeHeadersHeader, strings.Join(ch.exposedHeaders, ","))
+	}
+
+	if ch.allowCredentials {
+		w.Header().Set(corsAllowCredentialsHeader, "true")
+	}
+
+	if len(ch.allowedOrigins) > 1 {
+		w.Header().Set(corsVaryHeader, corsOriginHeader)
+	}
+
+	returnOrigin := origin
+	if ch.allowedOriginValidator == nil && len(ch.allowedOrigins) == 0 {
+		returnOrigin = "*"
+	} else {
+		for _, o := range ch.allowedOrigins {
+			// A configuration of * is different than explicitly setting an allowed
+			// origin. Returning arbitrary origin headers in an access control allow
+			// origin header is unsafe and is not required by any use case.
+			if o == corsOriginMatchAll {
+				returnOrigin = "*"
+				break
+			}
+		}
+	}
+	w.Header().Set(corsAllowOriginHeader, returnOrigin)
+
+	if r.Method == corsOptionMethod {
+		w.WriteHeader(ch.optionStatusCode)
+		return
+	}
+	ch.h.ServeHTTP(w, r)
+}
+
+// CORS provides Cross-Origin Resource Sharing middleware.
+// Example:
+//
+//	import (
+//	    "net/http"
+//
+//	    "github.com/gorilla/handlers"
+//	    "github.com/gorilla/mux"
+//	)
+//
+//	func main() {
+//	    r := mux.NewRouter()
+//	    r.HandleFunc("/users", UserEndpoint)
+//	    r.HandleFunc("/projects", ProjectEndpoint)
+//
+//	    // Apply the CORS middleware to our top-level router, with the defaults.
+//	    http.ListenAndServe(":8000", handlers.CORS()(r))
+//	}
+func CORS(opts ...CORSOption) func(http.Handler) http.Handler {
+	return func(h http.Handler) http.Handler {
+		ch := parseCORSOptions(opts...)
+		ch.h = h
+		return ch
+	}
+}
+
+func parseCORSOptions(opts ...CORSOption) *cors {
+	ch := &cors{
+		allowedMethods:   defaultCorsMethods,
+		allowedHeaders:   defaultCorsHeaders,
+		allowedOrigins:   []string{},
+		optionStatusCode: defaultCorsOptionStatusCode,
+	}
+
+	for _, option := range opts {
+		_ = option(ch) //TODO: @bharat-rajani, return error to caller if not nil?
+	}
+
+	return ch
+}
+
+//
+// Functional options for configuring CORS.
+//
+
+// AllowedHeaders adds the provided headers to the list of allowed headers in a
+// CORS request.
+// This is an append operation so the headers Accept, Accept-Language,
+// and Content-Language are always allowed.
+// Content-Type must be explicitly declared if accepting Content-Types other than
+// application/x-www-form-urlencoded, multipart/form-data, or text/plain.
+func AllowedHeaders(headers []string) CORSOption {
+	return func(ch *cors) error {
+		for _, v := range headers {
+			normalizedHeader := http.CanonicalHeaderKey(strings.TrimSpace(v))
+			if normalizedHeader == "" {
+				continue
+			}
+
+			if !ch.isMatch(normalizedHeader, ch.allowedHeaders) {
+				ch.allowedHeaders = append(ch.allowedHeaders, normalizedHeader)
+			}
+		}
+
+		return nil
+	}
+}
+
+// AllowedMethods can be used to explicitly allow methods in the
+// Access-Control-Allow-Methods header.
+// This is a replacement operation so you must also
+// pass GET, HEAD, and POST if you wish to support those methods.
+func AllowedMethods(methods []string) CORSOption {
+	return func(ch *cors) error {
+		ch.allowedMethods = []string{}
+		for _, v := range methods {
+			normalizedMethod := strings.ToUpper(strings.TrimSpace(v))
+			if normalizedMethod == "" {
+				continue
+			}
+
+			if !ch.isMatch(normalizedMethod, ch.allowedMethods) {
+				ch.allowedMethods = append(ch.allowedMethods, normalizedMethod)
+			}
+		}
+
+		return nil
+	}
+}
+
+// AllowedOrigins sets the allowed origins for CORS requests, as used in the
+// 'Allow-Access-Control-Origin' HTTP header.
+// Note: Passing in a []string{"*"} will allow any domain.
+func AllowedOrigins(origins []string) CORSOption {
+	return func(ch *cors) error {
+		for _, v := range origins {
+			if v == corsOriginMatchAll {
+				ch.allowedOrigins = []string{corsOriginMatchAll}
+				return nil
+			}
+		}
+
+		ch.allowedOrigins = origins
+		return nil
+	}
+}
+
+// AllowedOriginValidator sets a function for evaluating allowed origins in CORS requests, represented by the
+// 'Allow-Access-Control-Origin' HTTP header.
+func AllowedOriginValidator(fn OriginValidator) CORSOption {
+	return func(ch *cors) error {
+		ch.allowedOriginValidator = fn
+		return nil
+	}
+}
+
+// OptionStatusCode sets a custom status code on the OPTIONS requests.
+// Default behaviour sets it to 200 to reflect best practices. This is option is not mandatory
+// and can be used if you need a custom status code (i.e 204).
+//
+// More informations on the spec:
+// https://fetch.spec.whatwg.org/#cors-preflight-fetch
+func OptionStatusCode(code int) CORSOption {
+	return func(ch *cors) error {
+		ch.optionStatusCode = code
+		return nil
+	}
+}
+
+// ExposedHeaders can be used to specify headers that are available
+// and will not be stripped out by the user-agent.
+func ExposedHeaders(headers []string) CORSOption {
+	return func(ch *cors) error {
+		ch.exposedHeaders = []string{}
+		for _, v := range headers {
+			normalizedHeader := http.CanonicalHeaderKey(strings.TrimSpace(v))
+			if normalizedHeader == "" {
+				continue
+			}
+
+			if !ch.isMatch(normalizedHeader, ch.exposedHeaders) {
+				ch.exposedHeaders = append(ch.exposedHeaders, normalizedHeader)
+			}
+		}
+
+		return nil
+	}
+}
+
+// MaxAge determines the maximum age (in seconds) between preflight requests. A
+// maximum of 10 minutes is allowed. An age above this value will default to 10
+// minutes.
+func MaxAge(age int) CORSOption {
+	return func(ch *cors) error {
+		// Maximum of 10 minutes.
+		if age > 600 {
+			age = 600
+		}
+
+		ch.maxAge = age
+		return nil
+	}
+}
+
+// IgnoreOptions causes the CORS middleware to ignore OPTIONS requests, instead
+// passing them through to the next handler. This is useful when your application
+// or framework has a pre-existing mechanism for responding to OPTIONS requests.
+func IgnoreOptions() CORSOption {
+	return func(ch *cors) error {
+		ch.ignoreOptions = true
+		return nil
+	}
+}
+
+// AllowCredentials can be used to specify that the user agent may pass
+// authentication details along with the request.
+func AllowCredentials() CORSOption {
+	return func(ch *cors) error {
+		ch.allowCredentials = true
+		return nil
+	}
+}
+
+func (ch *cors) isOriginAllowed(origin string) bool {
+	if origin == "" {
+		return false
+	}
+
+	if ch.allowedOriginValidator != nil {
+		return ch.allowedOriginValidator(origin)
+	}
+
+	if len(ch.allowedOrigins) == 0 {
+		return true
+	}
+
+	for _, allowedOrigin := range ch.allowedOrigins {
+		if allowedOrigin == origin || allowedOrigin == corsOriginMatchAll {
+			return true
+		}
+	}
+
+	return false
+}
+
+func (ch *cors) isMatch(needle string, haystack []string) bool {
+	for _, v := range haystack {
+		if v == needle {
+			return true
+		}
+	}
+
+	return false
+}

vendor/github.com/gorilla/handlers/doc.go

@@ -0,0 +1,9 @@
+/*
+Package handlers is a collection of handlers (aka "HTTP middleware") for use
+with Go's net/http package (or any framework supporting http.Handler).
+
+The package includes handlers for logging in standardised formats, compressing
+HTTP responses, validating content types and other useful tools for manipulating
+requests and responses.
+*/
+package handlers

vendor/github.com/gorilla/handlers/handlers.go

@@ -0,0 +1,150 @@
+// Copyright 2013 The Gorilla Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package handlers
+
+import (
+	"bufio"
+	"fmt"
+	"net"
+	"net/http"
+	"sort"
+	"strings"
+)
+
+// MethodHandler is an http.Handler that dispatches to a handler whose key in the
+// MethodHandler's map matches the name of the HTTP request's method, eg: GET
+//
+// If the request's method is OPTIONS and OPTIONS is not a key in the map then
+// the handler responds with a status of 200 and sets the Allow header to a
+// comma-separated list of available methods.
+//
+// If the request's method doesn't match any of its keys the handler responds
+// with a status of HTTP 405 "Method Not Allowed" and sets the Allow header to a
+// comma-separated list of available methods.
+type MethodHandler map[string]http.Handler
+
+func (h MethodHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
+	if handler, ok := h[req.Method]; ok {
+		handler.ServeHTTP(w, req)
+	} else {
+		allow := []string{}
+		for k := range h {
+			allow = append(allow, k)
+		}
+		sort.Strings(allow)
+		w.Header().Set("Allow", strings.Join(allow, ", "))
+		if req.Method == http.MethodOptions {
+			w.WriteHeader(http.StatusOK)
+		} else {
+			http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+		}
+	}
+}
+
+// responseLogger is wrapper of http.ResponseWriter that keeps track of its HTTP
+// status code and body size.
+type responseLogger struct {
+	w      http.ResponseWriter
+	status int
+	size   int
+}
+
+func (l *responseLogger) Write(b []byte) (int, error) {
+	size, err := l.w.Write(b)
+	l.size += size
+	return size, err
+}
+
+func (l *responseLogger) WriteHeader(s int) {
+	l.w.WriteHeader(s)
+	l.status = s
+}
+
+func (l *responseLogger) Status() int {
+	return l.status
+}
+
+func (l *responseLogger) Size() int {
+	return l.size
+}
+
+func (l *responseLogger) Hijack() (net.Conn, *bufio.ReadWriter, error) {
+	conn, rw, err := l.w.(http.Hijacker).Hijack()
+	if err == nil && l.status == 0 {
+		// The status will be StatusSwitchingProtocols if there was no error and
+		// WriteHeader has not been called yet
+		l.status = http.StatusSwitchingProtocols
+	}
+	return conn, rw, err
+}
+
+// isContentType validates the Content-Type header matches the supplied
+// contentType. That is, its type and subtype match.
+func isContentType(h http.Header, contentType string) bool {
+	ct := h.Get("Content-Type")
+	if i := strings.IndexRune(ct, ';'); i != -1 {
+		ct = ct[0:i]
+	}
+	return ct == contentType
+}
+
+// ContentTypeHandler wraps and returns a http.Handler, validating the request
+// content type is compatible with the contentTypes list. It writes a HTTP 415
+// error if that fails.
+//
+// Only PUT, POST, and PATCH requests are considered.
+func ContentTypeHandler(h http.Handler, contentTypes ...string) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if !(r.Method == http.MethodPut || r.Method == http.MethodPost || r.Method == http.MethodPatch) {
+			h.ServeHTTP(w, r)
+			return
+		}
+
+		for _, ct := range contentTypes {
+			if isContentType(r.Header, ct) {
+				h.ServeHTTP(w, r)
+				return
+			}
+		}
+		http.Error(w, fmt.Sprintf("Unsupported content type %q; expected one of %q",
+			r.Header.Get("Content-Type"),
+			contentTypes),
+			http.StatusUnsupportedMediaType)
+	})
+}
+
+const (
+	// HTTPMethodOverrideHeader is a commonly used
+	// http header to override a request method.
+	HTTPMethodOverrideHeader = "X-HTTP-Method-Override"
+	// HTTPMethodOverrideFormKey is a commonly used
+	// HTML form key to override a request method.
+	HTTPMethodOverrideFormKey = "_method"
+)
+
+// HTTPMethodOverrideHandler wraps and returns a http.Handler which checks for
+// the X-HTTP-Method-Override header or the _method form key, and overrides (if
+// valid) request.Method with its value.
+//
+// This is especially useful for HTTP clients that don't support many http verbs.
+// It isn't secure to override e.g a GET to a POST, so only POST requests are
+// considered.  Likewise, the override method can only be a "write" method: PUT,
+// PATCH or DELETE.
+//
+// Form method takes precedence over header method.
+func HTTPMethodOverrideHandler(h http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.Method == http.MethodPost {
+			om := r.FormValue(HTTPMethodOverrideFormKey)
+			if om == "" {
+				om = r.Header.Get(HTTPMethodOverrideHeader)
+			}
+			if om == http.MethodPut || om == http.MethodPatch || om == http.MethodDelete {
+				r.Method = om
+			}
+		}
+		h.ServeHTTP(w, r)
+	})
+}

vendor/github.com/gorilla/handlers/logging.go

@@ -0,0 +1,246 @@
+// Copyright 2013 The Gorilla Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package handlers
+
+import (
+	"io"
+	"net"
+	"net/http"
+	"net/url"
+	"strconv"
+	"time"
+	"unicode/utf8"
+
+	"github.com/felixge/httpsnoop"
+)
+
+// Logging
+
+// LogFormatterParams is the structure any formatter will be handed when time to log comes.
+type LogFormatterParams struct {
+	Request    *http.Request
+	URL        url.URL
+	TimeStamp  time.Time
+	StatusCode int
+	Size       int
+}
+
+// LogFormatter gives the signature of the formatter function passed to CustomLoggingHandler.
+type LogFormatter func(writer io.Writer, params LogFormatterParams)
+
+// loggingHandler is the http.Handler implementation for LoggingHandlerTo and its
+// friends
+
+type loggingHandler struct {
+	writer    io.Writer
+	handler   http.Handler
+	formatter LogFormatter
+}
+
+func (h loggingHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
+	t := time.Now()
+	logger, w := makeLogger(w)
+	url := *req.URL
+
+	h.handler.ServeHTTP(w, req)
+	if req.MultipartForm != nil {
+		err := req.MultipartForm.RemoveAll()
+		if err != nil {
+			return
+		}
+	}
+
+	params := LogFormatterParams{
+		Request:    req,
+		URL:        url,
+		TimeStamp:  t,
+		StatusCode: logger.Status(),
+		Size:       logger.Size(),
+	}
+
+	h.formatter(h.writer, params)
+}
+
+func makeLogger(w http.ResponseWriter) (*responseLogger, http.ResponseWriter) {
+	logger := &responseLogger{w: w, status: http.StatusOK}
+	return logger, httpsnoop.Wrap(w, httpsnoop.Hooks{
+		Write: func(httpsnoop.WriteFunc) httpsnoop.WriteFunc {
+			return logger.Write
+		},
+		WriteHeader: func(httpsnoop.WriteHeaderFunc) httpsnoop.WriteHeaderFunc {
+			return logger.WriteHeader
+		},
+	})
+}
+
+const lowerhex = "0123456789abcdef"
+
+func appendQuoted(buf []byte, s string) []byte {
+	var runeTmp [utf8.UTFMax]byte
+	for width := 0; len(s) > 0; s = s[width:] { //nolint: wastedassign //TODO: why width starts from 0and reassigned as 1
+		r := rune(s[0])
+		width = 1
+		if r >= utf8.RuneSelf {
+			r, width = utf8.DecodeRuneInString(s)
+		}
+		if width == 1 && r == utf8.RuneError {
+			buf = append(buf, `\x`...)
+			buf = append(buf, lowerhex[s[0]>>4])
+			buf = append(buf, lowerhex[s[0]&0xF])
+			continue
+		}
+		if r == rune('"') || r == '\\' { // always backslashed
+			buf = append(buf, '\\')
+			buf = append(buf, byte(r))
+			continue
+		}
+		if strconv.IsPrint(r) {
+			n := utf8.EncodeRune(runeTmp[:], r)
+			buf = append(buf, runeTmp[:n]...)
+			continue
+		}
+		switch r {
+		case '\a':
+			buf = append(buf, `\a`...)
+		case '\b':
+			buf = append(buf, `\b`...)
+		case '\f':
+			buf = append(buf, `\f`...)
+		case '\n':
+			buf = append(buf, `\n`...)
+		case '\r':
+			buf = append(buf, `\r`...)
+		case '\t':
+			buf = append(buf, `\t`...)
+		case '\v':
+			buf = append(buf, `\v`...)
+		default:
+			switch {
+			case r < ' ':
+				buf = append(buf, `\x`...)
+				buf = append(buf, lowerhex[s[0]>>4])
+				buf = append(buf, lowerhex[s[0]&0xF])
+			case r > utf8.MaxRune:
+				r = 0xFFFD
+				fallthrough
+			case r < 0x10000:
+				buf = append(buf, `\u`...)
+				for s := 12; s >= 0; s -= 4 {
+					buf = append(buf, lowerhex[r>>uint(s)&0xF])
+				}
+			default:
+				buf = append(buf, `\U`...)
+				for s := 28; s >= 0; s -= 4 {
+					buf = append(buf, lowerhex[r>>uint(s)&0xF])
+				}
+			}
+		}
+	}
+	return buf
+}
+
+// buildCommonLogLine builds a log entry for req in Apache Common Log Format.
+// ts is the timestamp with which the entry should be logged.
+// status and size are used to provide the response HTTP status and size.
+func buildCommonLogLine(req *http.Request, url url.URL, ts time.Time, status int, size int) []byte {
+	username := "-"
+	if url.User != nil {
+		if name := url.User.Username(); name != "" {
+			username = name
+		}
+	}
+
+	host, _, err := net.SplitHostPort(req.RemoteAddr)
+	if err != nil {
+		host = req.RemoteAddr
+	}
+
+	uri := req.RequestURI
+
+	// Requests using the CONNECT method over HTTP/2.0 must use
+	// the authority field (aka r.Host) to identify the target.
+	// Refer: https://httpwg.github.io/specs/rfc7540.html#CONNECT
+	if req.ProtoMajor == 2 && req.Method == "CONNECT" {
+		uri = req.Host
+	}
+	if uri == "" {
+		uri = url.RequestURI()
+	}
+
+	buf := make([]byte, 0, 3*(len(host)+len(username)+len(req.Method)+len(uri)+len(req.Proto)+50)/2)
+	buf = append(buf, host...)
+	buf = append(buf, " - "...)
+	buf = append(buf, username...)
+	buf = append(buf, " ["...)
+	buf = append(buf, ts.Format("02/Jan/2006:15:04:05 -0700")...)
+	buf = append(buf, `] "`...)
+	buf = append(buf, req.Method...)
+	buf = append(buf, " "...)
+	buf = appendQuoted(buf, uri)
+	buf = append(buf, " "...)
+	buf = append(buf, req.Proto...)
+	buf = append(buf, `" `...)
+	buf = append(buf, strconv.Itoa(status)...)
+	buf = append(buf, " "...)
+	buf = append(buf, strconv.Itoa(size)...)
+	return buf
+}
+
+// writeLog writes a log entry for req to w in Apache Common Log Format.
+// ts is the timestamp with which the entry should be logged.
+// status and size are used to provide the response HTTP status and size.
+func writeLog(writer io.Writer, params LogFormatterParams) {
+	buf := buildCommonLogLine(params.Request, params.URL, params.TimeStamp, params.StatusCode, params.Size)
+	buf = append(buf, '\n')
+	_, _ = writer.Write(buf)
+}
+
+// writeCombinedLog writes a log entry for req to w in Apache Combined Log Format.
+// ts is the timestamp with which the entry should be logged.
+// status and size are used to provide the response HTTP status and size.
+func writeCombinedLog(writer io.Writer, params LogFormatterParams) {
+	buf := buildCommonLogLine(params.Request, params.URL, params.TimeStamp, params.StatusCode, params.Size)
+	buf = append(buf, ` "`...)
+	buf = appendQuoted(buf, params.Request.Referer())
+	buf = append(buf, `" "`...)
+	buf = appendQuoted(buf, params.Request.UserAgent())
+	buf = append(buf, '"', '\n')
+	_, _ = writer.Write(buf)
+}
+
+// CombinedLoggingHandler return a http.Handler that wraps h and logs requests to out in
+// Apache Combined Log Format.
+//
+// See http://httpd.apache.org/docs/2.2/logs.html#combined for a description of this format.
+//
+// LoggingHandler always sets the ident field of the log to -.
+func CombinedLoggingHandler(out io.Writer, h http.Handler) http.Handler {
+	return loggingHandler{out, h, writeCombinedLog}
+}
+
+// LoggingHandler return a http.Handler that wraps h and logs requests to out in
+// Apache Common Log Format (CLF).
+//
+// See http://httpd.apache.org/docs/2.2/logs.html#common for a description of this format.
+//
+// LoggingHandler always sets the ident field of the log to -
+//
+// Example:
+//
+//	r := mux.NewRouter()
+//	r.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+//		w.Write([]byte("This is a catch-all route"))
+//	})
+//	loggedRouter := handlers.LoggingHandler(os.Stdout, r)
+//	http.ListenAndServe(":1123", loggedRouter)
+func LoggingHandler(out io.Writer, h http.Handler) http.Handler {
+	return loggingHandler{out, h, writeLog}
+}
+
+// CustomLoggingHandler provides a way to supply a custom log formatter
+// while taking advantage of the mechanisms in this package.
+func CustomLoggingHandler(out io.Writer, h http.Handler, f LogFormatter) http.Handler {
+	return loggingHandler{out, h, f}
+}

vendor/github.com/gorilla/handlers/proxy_headers.go

@@ -0,0 +1,120 @@
+package handlers
+
+import (
+	"net/http"
+	"regexp"
+	"strings"
+)
+
+var (
+	// De-facto standard header keys.
+	xForwardedFor    = http.CanonicalHeaderKey("X-Forwarded-For")
+	xForwardedHost   = http.CanonicalHeaderKey("X-Forwarded-Host")
+	xForwardedProto  = http.CanonicalHeaderKey("X-Forwarded-Proto")
+	xForwardedScheme = http.CanonicalHeaderKey("X-Forwarded-Scheme")
+	xRealIP          = http.CanonicalHeaderKey("X-Real-IP")
+)
+
+var (
+	// RFC7239 defines a new "Forwarded: " header designed to replace the
+	// existing use of X-Forwarded-* headers.
+	// e.g. Forwarded: for=192.0.2.60;proto=https;by=203.0.113.43.
+	forwarded = http.CanonicalHeaderKey("Forwarded")
+	// Allows for a sub-match of the first value after 'for=' to the next
+	// comma, semi-colon or space. The match is case-insensitive.
+	forRegex = regexp.MustCompile(`(?i)(?:for=)([^(;|,| )]+)`)
+	// Allows for a sub-match for the first instance of scheme (http|https)
+	// prefixed by 'proto='. The match is case-insensitive.
+	protoRegex = regexp.MustCompile(`(?i)(?:proto=)(https|http)`)
+)
+
+// ProxyHeaders inspects common reverse proxy headers and sets the corresponding
+// fields in the HTTP request struct. These are X-Forwarded-For and X-Real-IP
+// for the remote (client) IP address, X-Forwarded-Proto or X-Forwarded-Scheme
+// for the scheme (http|https), X-Forwarded-Host for the host and the RFC7239
+// Forwarded header, which may include both client IPs and schemes.
+//
+// NOTE: This middleware should only be used when behind a reverse
+// proxy like nginx, HAProxy or Apache. Reverse proxies that don't (or are
+// configured not to) strip these headers from client requests, or where these
+// headers are accepted "as is" from a remote client (e.g. when Go is not behind
+// a proxy), can manifest as a vulnerability if your application uses these
+// headers for validating the 'trustworthiness' of a request.
+func ProxyHeaders(h http.Handler) http.Handler {
+	fn := func(w http.ResponseWriter, r *http.Request) {
+		// Set the remote IP with the value passed from the proxy.
+		if fwd := getIP(r); fwd != "" {
+			r.RemoteAddr = fwd
+		}
+
+		// Set the scheme (proto) with the value passed from the proxy.
+		if scheme := getScheme(r); scheme != "" {
+			r.URL.Scheme = scheme
+		}
+		// Set the host with the value passed by the proxy
+		if r.Header.Get(xForwardedHost) != "" {
+			r.Host = r.Header.Get(xForwardedHost)
+		}
+		// Call the next handler in the chain.
+		h.ServeHTTP(w, r)
+	}
+
+	return http.HandlerFunc(fn)
+}
+
+// getIP retrieves the IP from the X-Forwarded-For, X-Real-IP and RFC7239
+// Forwarded headers (in that order).
+func getIP(r *http.Request) string {
+	var addr string
+
+	switch {
+	case r.Header.Get(xForwardedFor) != "":
+		fwd := r.Header.Get(xForwardedFor)
+		// Only grab the first (client) address. Note that '192.168.0.1,
+		// 10.1.1.1' is a valid key for X-Forwarded-For where addresses after
+		// the first may represent forwarding proxies earlier in the chain.
+		s := strings.Index(fwd, ", ")
+		if s == -1 {
+			s = len(fwd)
+		}
+		addr = fwd[:s]
+	case r.Header.Get(xRealIP) != "":
+		addr = r.Header.Get(xRealIP)
+	case r.Header.Get(forwarded) != "":
+		// match should contain at least two elements if the protocol was
+		// specified in the Forwarded header. The first element will always be
+		// the 'for=' capture, which we ignore. In the case of multiple IP
+		// addresses (for=8.8.8.8, 8.8.4.4,172.16.1.20 is valid) we only
+		// extract the first, which should be the client IP.
+		if match := forRegex.FindStringSubmatch(r.Header.Get(forwarded)); len(match) > 1 {
+			// IPv6 addresses in Forwarded headers are quoted-strings. We strip
+			// these quotes.
+			addr = strings.Trim(match[1], `"`)
+		}
+	}
+
+	return addr
+}
+
+// getScheme retrieves the scheme from the X-Forwarded-Proto and RFC7239
+// Forwarded headers (in that order).
+func getScheme(r *http.Request) string {
+	var scheme string
+
+	// Retrieve the scheme from X-Forwarded-Proto.
+	if proto := r.Header.Get(xForwardedProto); proto != "" {
+		scheme = strings.ToLower(proto)
+	} else if proto = r.Header.Get(xForwardedScheme); proto != "" {
+		scheme = strings.ToLower(proto)
+	} else if proto = r.Header.Get(forwarded); proto != "" {
+		// match should contain at least two elements if the protocol was
+		// specified in the Forwarded header. The first element will always be
+		// the 'proto=' capture, which we ignore. In the case of multiple proto
+		// parameters (invalid) we only extract the first.
+		if match := protoRegex.FindStringSubmatch(proto); len(match) > 1 {
+			scheme = strings.ToLower(match[1])
+		}
+	}
+
+	return scheme
+}

vendor/github.com/gorilla/handlers/recovery.go

@@ -0,0 +1,98 @@
+package handlers
+
+import (
+	"log"
+	"net/http"
+	"runtime/debug"
+)
+
+// RecoveryHandlerLogger is an interface used by the recovering handler to print logs.
+type RecoveryHandlerLogger interface {
+	Println(...interface{})
+}
+
+type recoveryHandler struct {
+	handler    http.Handler
+	logger     RecoveryHandlerLogger
+	printStack bool
+}
+
+// RecoveryOption provides a functional approach to define
+// configuration for a handler; such as setting the logging
+// whether or not to print stack traces on panic.
+type RecoveryOption func(http.Handler)
+
+func parseRecoveryOptions(h http.Handler, opts ...RecoveryOption) http.Handler {
+	for _, option := range opts {
+		option(h)
+	}
+
+	return h
+}
+
+// RecoveryHandler is HTTP middleware that recovers from a panic,
+// logs the panic, writes http.StatusInternalServerError, and
+// continues to the next handler.
+//
+// Example:
+//
+//	r := mux.NewRouter()
+//	r.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+//		panic("Unexpected error!")
+//	})
+//
+//	http.ListenAndServe(":1123", handlers.RecoveryHandler()(r))
+func RecoveryHandler(opts ...RecoveryOption) func(h http.Handler) http.Handler {
+	return func(h http.Handler) http.Handler {
+		r := &recoveryHandler{handler: h}
+		return parseRecoveryOptions(r, opts...)
+	}
+}
+
+// RecoveryLogger is a functional option to override
+// the default logger.
+func RecoveryLogger(logger RecoveryHandlerLogger) RecoveryOption {
+	return func(h http.Handler) {
+		r := h.(*recoveryHandler) //nolint:errcheck //TODO:
+		// @bharat-rajani should return type-assertion error but would break the API?
+		r.logger = logger
+	}
+}
+
+// PrintRecoveryStack is a functional option to enable
+// or disable printing stack traces on panic.
+func PrintRecoveryStack(shouldPrint bool) RecoveryOption {
+	return func(h http.Handler) {
+		r := h.(*recoveryHandler) //nolint:errcheck //TODO:
+		// @bharat-rajani should return type-assertion error but would break the API?
+		r.printStack = shouldPrint
+	}
+}
+
+func (h recoveryHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
+	defer func() {
+		if err := recover(); err != nil {
+			w.WriteHeader(http.StatusInternalServerError)
+			h.log(err)
+		}
+	}()
+
+	h.handler.ServeHTTP(w, req)
+}
+
+func (h recoveryHandler) log(v ...interface{}) {
+	if h.logger != nil {
+		h.logger.Println(v...)
+	} else {
+		log.Println(v...)
+	}
+
+	if h.printStack {
+		stack := string(debug.Stack())
+		if h.logger != nil {
+			h.logger.Println(stack)
+		} else {
+			log.Println(stack)
+		}
+	}
+}

vendor/github.com/gorilla/mux/.editorconfig

@@ -0,0 +1,20 @@
+; https://editorconfig.org/
+
+root = true
+
+[*]
+insert_final_newline = true
+charset = utf-8
+trim_trailing_whitespace = true
+indent_style = space
+indent_size = 2
+
+[{Makefile,go.mod,go.sum,*.go,.gitmodules}]
+indent_style = tab
+indent_size = 4
+
+[*.md]
+indent_size = 4
+trim_trailing_whitespace = false
+
+eclint_indent_style = unset

vendor/github.com/gorilla/mux/.gitignore

@@ -0,0 +1 @@
+coverage.coverprofile

vendor/github.com/gorilla/mux/LICENSE

@@ -0,0 +1,27 @@
+Copyright (c) 2023 The Gorilla Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+	 * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+	 * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+	 * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

vendor/github.com/gorilla/mux/Makefile

@@ -0,0 +1,34 @@
+GO_LINT=$(shell which golangci-lint 2> /dev/null || echo '')
+GO_LINT_URI=github.com/golangci/golangci-lint/cmd/golangci-lint@latest
+
+GO_SEC=$(shell which gosec 2> /dev/null || echo '')
+GO_SEC_URI=github.com/securego/gosec/v2/cmd/gosec@latest
+
+GO_VULNCHECK=$(shell which govulncheck 2> /dev/null || echo '')
+GO_VULNCHECK_URI=golang.org/x/vuln/cmd/govulncheck@latest
+
+.PHONY: golangci-lint
+golangci-lint:
+	$(if $(GO_LINT), ,go install $(GO_LINT_URI))
+	@echo "##### Running golangci-lint"
+	golangci-lint run -v
+	
+.PHONY: gosec
+gosec:
+	$(if $(GO_SEC), ,go install $(GO_SEC_URI))
+	@echo "##### Running gosec"
+	gosec ./...
+
+.PHONY: govulncheck
+govulncheck:
+	$(if $(GO_VULNCHECK), ,go install $(GO_VULNCHECK_URI))
+	@echo "##### Running govulncheck"
+	govulncheck ./...
+
+.PHONY: verify
+verify: golangci-lint gosec govulncheck
+
+.PHONY: test
+test:
+	@echo "##### Running tests"
+	go test -race -cover -coverprofile=coverage.coverprofile -covermode=atomic -v ./...

vendor/github.com/gorilla/mux/README.md

@@ -0,0 +1,812 @@
+# gorilla/mux
+
+![testing](https://github.com/gorilla/mux/actions/workflows/test.yml/badge.svg)
+[![codecov](https://codecov.io/github/gorilla/mux/branch/main/graph/badge.svg)](https://codecov.io/github/gorilla/mux)
+[![godoc](https://godoc.org/github.com/gorilla/mux?status.svg)](https://godoc.org/github.com/gorilla/mux)
+[![sourcegraph](https://sourcegraph.com/github.com/gorilla/mux/-/badge.svg)](https://sourcegraph.com/github.com/gorilla/mux?badge)
+
+
+![Gorilla Logo](https://github.com/gorilla/.github/assets/53367916/d92caabf-98e0-473e-bfbf-ab554ba435e5)
+
+Package `gorilla/mux` implements a request router and dispatcher for matching incoming requests to
+their respective handler.
+
+The name mux stands for "HTTP request multiplexer". Like the standard `http.ServeMux`, `mux.Router` matches incoming requests against a list of registered routes and calls a handler for the route that matches the URL or other conditions. The main features are:
+
+* It implements the `http.Handler` interface so it is compatible with the standard `http.ServeMux`.
+* Requests can be matched based on URL host, path, path prefix, schemes, header and query values, HTTP methods or using custom matchers.
+* URL hosts, paths and query values can have variables with an optional regular expression.
+* Registered URLs can be built, or "reversed", which helps maintaining references to resources.
+* Routes can be used as subrouters: nested routes are only tested if the parent route matches. This is useful to define groups of routes that share common conditions like a host, a path prefix or other repeated attributes. As a bonus, this optimizes request matching.
+
+---
+
+* [Install](#install)
+* [Examples](#examples)
+* [Matching Routes](#matching-routes)
+* [Static Files](#static-files)
+* [Serving Single Page Applications](#serving-single-page-applications) (e.g. React, Vue, Ember.js, etc.)
+* [Registered URLs](#registered-urls)
+* [Walking Routes](#walking-routes)
+* [Graceful Shutdown](#graceful-shutdown)
+* [Middleware](#middleware)
+* [Handling CORS Requests](#handling-cors-requests)
+* [Testing Handlers](#testing-handlers)
+* [Full Example](#full-example)
+
+---
+
+## Install
+
+With a [correctly configured](https://golang.org/doc/install#testing) Go toolchain:
+
+```sh
+go get -u github.com/gorilla/mux
+```
+
+## Examples
+
+Let's start registering a couple of URL paths and handlers:
+
+```go
+func main() {
+    r := mux.NewRouter()
+    r.HandleFunc("/", HomeHandler)
+    r.HandleFunc("/products", ProductsHandler)
+    r.HandleFunc("/articles", ArticlesHandler)
+    http.Handle("/", r)
+}
+```
+
+Here we register three routes mapping URL paths to handlers. This is equivalent to how `http.HandleFunc()` works: if an incoming request URL matches one of the paths, the corresponding handler is called passing (`http.ResponseWriter`, `*http.Request`) as parameters.
+
+Paths can have variables. They are defined using the format `{name}` or `{name:pattern}`. If a regular expression pattern is not defined, the matched variable will be anything until the next slash. For example:
+
+```go
+r := mux.NewRouter()
+r.HandleFunc("/products/{key}", ProductHandler)
+r.HandleFunc("/articles/{category}/", ArticlesCategoryHandler)
+r.HandleFunc("/articles/{category}/{id:[0-9]+}", ArticleHandler)
+```
+
+The names are used to create a map of route variables which can be retrieved calling `mux.Vars()`:
+
+```go
+func ArticlesCategoryHandler(w http.ResponseWriter, r *http.Request) {
+    vars := mux.Vars(r)
+    w.WriteHeader(http.StatusOK)
+    fmt.Fprintf(w, "Category: %v\n", vars["category"])
+}
+```
+
+And this is all you need to know about the basic usage. More advanced options are explained below.
+
+### Matching Routes
+
+Routes can also be restricted to a domain or subdomain. Just define a host pattern to be matched. They can also have variables:
+
+```go
+r := mux.NewRouter()
+// Only matches if domain is "www.example.com".
+r.Host("www.example.com")
+// Matches a dynamic subdomain.
+r.Host("{subdomain:[a-z]+}.example.com")
+```
+
+There are several other matchers that can be added. To match path prefixes:
+
+```go
+r.PathPrefix("/products/")
+```
+
+...or HTTP methods:
+
+```go
+r.Methods("GET", "POST")
+```
+
+...or URL schemes:
+
+```go
+r.Schemes("https")
+```
+
+...or header values:
+
+```go
+r.Headers("X-Requested-With", "XMLHttpRequest")
+```
+
+...or query values:
+
+```go
+r.Queries("key", "value")
+```
+
+...or to use a custom matcher function:
+
+```go
+r.MatcherFunc(func(r *http.Request, rm *RouteMatch) bool {
+    return r.ProtoMajor == 0
+})
+```
+
+...and finally, it is possible to combine several matchers in a single route:
+
+```go
+r.HandleFunc("/products", ProductsHandler).
+  Host("www.example.com").
+  Methods("GET").
+  Schemes("http")
+```
+
+Routes are tested in the order they were added to the router. If two routes match, the first one wins:
+
+```go
+r := mux.NewRouter()
+r.HandleFunc("/specific", specificHandler)
+r.PathPrefix("/").Handler(catchAllHandler)
+```
+
+Setting the same matching conditions again and again can be boring, so we have a way to group several routes that share the same requirements. We call it "subrouting".
+
+For example, let's say we have several URLs that should only match when the host is `www.example.com`. Create a route for that host and get a "subrouter" from it:
+
+```go
+r := mux.NewRouter()
+s := r.Host("www.example.com").Subrouter()
+```
+
+Then register routes in the subrouter:
+
+```go
+s.HandleFunc("/products/", ProductsHandler)
+s.HandleFunc("/products/{key}", ProductHandler)
+s.HandleFunc("/articles/{category}/{id:[0-9]+}", ArticleHandler)
+```
+
+The three URL paths we registered above will only be tested if the domain is `www.example.com`, because the subrouter is tested first. This is not only convenient, but also optimizes request matching. You can create subrouters combining any attribute matchers accepted by a route.
+
+Subrouters can be used to create domain or path "namespaces": you define subrouters in a central place and then parts of the app can register its paths relatively to a given subrouter.
+
+There's one more thing about subroutes. When a subrouter has a path prefix, the inner routes use it as base for their paths:
+
+```go
+r := mux.NewRouter()
+s := r.PathPrefix("/products").Subrouter()
+// "/products/"
+s.HandleFunc("/", ProductsHandler)
+// "/products/{key}/"
+s.HandleFunc("/{key}/", ProductHandler)
+// "/products/{key}/details"
+s.HandleFunc("/{key}/details", ProductDetailsHandler)
+```
+
+
+### Static Files
+
+Note that the path provided to `PathPrefix()` represents a "wildcard": calling
+`PathPrefix("/static/").Handler(...)` means that the handler will be passed any
+request that matches "/static/\*". This makes it easy to serve static files with mux:
+
+```go
+func main() {
+    var dir string
+
+    flag.StringVar(&dir, "dir", ".", "the directory to serve files from. Defaults to the current dir")
+    flag.Parse()
+    r := mux.NewRouter()
+
+    // This will serve files under http://localhost:8000/static/<filename>
+    r.PathPrefix("/static/").Handler(http.StripPrefix("/static/", http.FileServer(http.Dir(dir))))
+
+    srv := &http.Server{
+        Handler:      r,
+        Addr:         "127.0.0.1:8000",
+        // Good practice: enforce timeouts for servers you create!
+        WriteTimeout: 15 * time.Second,
+        ReadTimeout:  15 * time.Second,
+    }
+
+    log.Fatal(srv.ListenAndServe())
+}
+```
+
+### Serving Single Page Applications
+
+Most of the time it makes sense to serve your SPA on a separate web server from your API,
+but sometimes it's desirable to serve them both from one place. It's possible to write a simple
+handler for serving your SPA (for use with React Router's [BrowserRouter](https://reacttraining.com/react-router/web/api/BrowserRouter) for example), and leverage
+mux's powerful routing for your API endpoints.
+
+```go
+package main
+
+import (
+	"encoding/json"
+	"log"
+	"net/http"
+	"os"
+	"path/filepath"
+	"time"
+
+	"github.com/gorilla/mux"
+)
+
+// spaHandler implements the http.Handler interface, so we can use it
+// to respond to HTTP requests. The path to the static directory and
+// path to the index file within that static directory are used to
+// serve the SPA in the given static directory.
+type spaHandler struct {
+	staticPath string
+	indexPath  string
+}
+
+// ServeHTTP inspects the URL path to locate a file within the static dir
+// on the SPA handler. If a file is found, it will be served. If not, the
+// file located at the index path on the SPA handler will be served. This
+// is suitable behavior for serving an SPA (single page application).
+func (h spaHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	// Join internally call path.Clean to prevent directory traversal
+	path := filepath.Join(h.staticPath, r.URL.Path)
+
+	// check whether a file exists or is a directory at the given path
+	fi, err := os.Stat(path)
+	if os.IsNotExist(err) || fi.IsDir() {
+		// file does not exist or path is a directory, serve index.html
+		http.ServeFile(w, r, filepath.Join(h.staticPath, h.indexPath))
+		return
+	}
+
+	if err != nil {
+		// if we got an error (that wasn't that the file doesn't exist) stating the
+		// file, return a 500 internal server error and stop
+		http.Error(w, err.Error(), http.StatusInternalServerError)
+        return
+	}
+
+	// otherwise, use http.FileServer to serve the static file
+	http.FileServer(http.Dir(h.staticPath)).ServeHTTP(w, r)
+}
+
+func main() {
+	router := mux.NewRouter()
+
+	router.HandleFunc("/api/health", func(w http.ResponseWriter, r *http.Request) {
+		// an example API handler
+		json.NewEncoder(w).Encode(map[string]bool{"ok": true})
+	})
+
+	spa := spaHandler{staticPath: "build", indexPath: "index.html"}
+	router.PathPrefix("/").Handler(spa)
+
+	srv := &http.Server{
+		Handler: router,
+		Addr:    "127.0.0.1:8000",
+		// Good practice: enforce timeouts for servers you create!
+		WriteTimeout: 15 * time.Second,
+		ReadTimeout:  15 * time.Second,
+	}
+
+	log.Fatal(srv.ListenAndServe())
+}
+```
+
+### Registered URLs
+
+Now let's see how to build registered URLs.
+
+Routes can be named. All routes that define a name can have their URLs built, or "reversed". We define a name calling `Name()` on a route. For example:
+
+```go
+r := mux.NewRouter()
+r.HandleFunc("/articles/{category}/{id:[0-9]+}", ArticleHandler).
+  Name("article")
+```
+
+To build a URL, get the route and call the `URL()` method, passing a sequence of key/value pairs for the route variables. For the previous route, we would do:
+
+```go
+url, err := r.Get("article").URL("category", "technology", "id", "42")
+```
+
+...and the result will be a `url.URL` with the following path:
+
+```
+"/articles/technology/42"
+```
+
+This also works for host and query value variables:
+
+```go
+r := mux.NewRouter()
+r.Host("{subdomain}.example.com").
+  Path("/articles/{category}/{id:[0-9]+}").
+  Queries("filter", "{filter}").
+  HandlerFunc(ArticleHandler).
+  Name("article")
+
+// url.String() will be "http://news.example.com/articles/technology/42?filter=gorilla"
+url, err := r.Get("article").URL("subdomain", "news",
+                                 "category", "technology",
+                                 "id", "42",
+                                 "filter", "gorilla")
+```
+
+All variables defined in the route are required, and their values must conform to the corresponding patterns. These requirements guarantee that a generated URL will always match a registered route -- the only exception is for explicitly defined "build-only" routes which never match.
+
+Regex support also exists for matching Headers within a route. For example, we could do:
+
+```go
+r.HeadersRegexp("Content-Type", "application/(text|json)")
+```
+
+...and the route will match both requests with a Content-Type of `application/json` as well as `application/text`
+
+There's also a way to build only the URL host or path for a route: use the methods `URLHost()` or `URLPath()` instead. For the previous route, we would do:
+
+```go
+// "http://news.example.com/"
+host, err := r.Get("article").URLHost("subdomain", "news")
+
+// "/articles/technology/42"
+path, err := r.Get("article").URLPath("category", "technology", "id", "42")
+```
+
+And if you use subrouters, host and path defined separately can be built as well:
+
+```go
+r := mux.NewRouter()
+s := r.Host("{subdomain}.example.com").Subrouter()
+s.Path("/articles/{category}/{id:[0-9]+}").
+  HandlerFunc(ArticleHandler).
+  Name("article")
+
+// "http://news.example.com/articles/technology/42"
+url, err := r.Get("article").URL("subdomain", "news",
+                                 "category", "technology",
+                                 "id", "42")
+```
+
+To find all the required variables for a given route when calling `URL()`, the method `GetVarNames()` is available:
+```go
+r := mux.NewRouter()
+r.Host("{domain}").
+    Path("/{group}/{item_id}").
+    Queries("some_data1", "{some_data1}").
+    Queries("some_data2", "{some_data2}").
+    Name("article")
+
+// Will print [domain group item_id some_data1 some_data2] <nil>
+fmt.Println(r.Get("article").GetVarNames())
+
+```
+### Walking Routes
+
+The `Walk` function on `mux.Router` can be used to visit all of the routes that are registered on a router. For example,
+the following prints all of the registered routes:
+
+```go
+package main
+
+import (
+	"fmt"
+	"net/http"
+	"strings"
+
+	"github.com/gorilla/mux"
+)
+
+func handler(w http.ResponseWriter, r *http.Request) {
+	return
+}
+
+func main() {
+	r := mux.NewRouter()
+	r.HandleFunc("/", handler)
+	r.HandleFunc("/products", handler).Methods("POST")
+	r.HandleFunc("/articles", handler).Methods("GET")
+	r.HandleFunc("/articles/{id}", handler).Methods("GET", "PUT")
+	r.HandleFunc("/authors", handler).Queries("surname", "{surname}")
+	err := r.Walk(func(route *mux.Route, router *mux.Router, ancestors []*mux.Route) error {
+		pathTemplate, err := route.GetPathTemplate()
+		if err == nil {
+			fmt.Println("ROUTE:", pathTemplate)
+		}
+		pathRegexp, err := route.GetPathRegexp()
+		if err == nil {
+			fmt.Println("Path regexp:", pathRegexp)
+		}
+		queriesTemplates, err := route.GetQueriesTemplates()
+		if err == nil {
+			fmt.Println("Queries templates:", strings.Join(queriesTemplates, ","))
+		}
+		queriesRegexps, err := route.GetQueriesRegexp()
+		if err == nil {
+			fmt.Println("Queries regexps:", strings.Join(queriesRegexps, ","))
+		}
+		methods, err := route.GetMethods()
+		if err == nil {
+			fmt.Println("Methods:", strings.Join(methods, ","))
+		}
+		fmt.Println()
+		return nil
+	})
+
+	if err != nil {
+		fmt.Println(err)
+	}
+
+	http.Handle("/", r)
+}
+```
+
+### Graceful Shutdown
+
+Go 1.8 introduced the ability to [gracefully shutdown](https://golang.org/doc/go1.8#http_shutdown) a `*http.Server`. Here's how to do that alongside `mux`:
+
+```go
+package main
+
+import (
+    "context"
+    "flag"
+    "log"
+    "net/http"
+    "os"
+    "os/signal"
+    "time"
+
+    "github.com/gorilla/mux"
+)
+
+func main() {
+    var wait time.Duration
+    flag.DurationVar(&wait, "graceful-timeout", time.Second * 15, "the duration for which the server gracefully wait for existing connections to finish - e.g. 15s or 1m")
+    flag.Parse()
+
+    r := mux.NewRouter()
+    // Add your routes as needed
+
+    srv := &http.Server{
+        Addr:         "0.0.0.0:8080",
+        // Good practice to set timeouts to avoid Slowloris attacks.
+        WriteTimeout: time.Second * 15,
+        ReadTimeout:  time.Second * 15,
+        IdleTimeout:  time.Second * 60,
+        Handler: r, // Pass our instance of gorilla/mux in.
+    }
+
+    // Run our server in a goroutine so that it doesn't block.
+    go func() {
+        if err := srv.ListenAndServe(); err != nil {
+            log.Println(err)
+        }
+    }()
+
+    c := make(chan os.Signal, 1)
+    // We'll accept graceful shutdowns when quit via SIGINT (Ctrl+C)
+    // SIGKILL, SIGQUIT or SIGTERM (Ctrl+/) will not be caught.
+    signal.Notify(c, os.Interrupt)
+
+    // Block until we receive our signal.
+    <-c
+
+    // Create a deadline to wait for.
+    ctx, cancel := context.WithTimeout(context.Background(), wait)
+    defer cancel()
+    // Doesn't block if no connections, but will otherwise wait
+    // until the timeout deadline.
+    srv.Shutdown(ctx)
+    // Optionally, you could run srv.Shutdown in a goroutine and block on
+    // <-ctx.Done() if your application should wait for other services
+    // to finalize based on context cancellation.
+    log.Println("shutting down")
+    os.Exit(0)
+}
+```
+
+### Middleware
+
+Mux supports the addition of middlewares to a [Router](https://godoc.org/github.com/gorilla/mux#Router), which are executed in the order they are added if a match is found, including its subrouters.
+Middlewares are (typically) small pieces of code which take one request, do something with it, and pass it down to another middleware or the final handler. Some common use cases for middleware are request logging, header manipulation, or `ResponseWriter` hijacking.
+
+Mux middlewares are defined using the de facto standard type:
+
+```go
+type MiddlewareFunc func(http.Handler) http.Handler
+```
+
+Typically, the returned handler is a closure which does something with the http.ResponseWriter and http.Request passed to it, and then calls the handler passed as parameter to the MiddlewareFunc. This takes advantage of closures being able access variables from the context where they are created, while retaining the signature enforced by the receivers.
+
+A very basic middleware which logs the URI of the request being handled could be written as:
+
+```go
+func loggingMiddleware(next http.Handler) http.Handler {
+    return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+        // Do stuff here
+        log.Println(r.RequestURI)
+        // Call the next handler, which can be another middleware in the chain, or the final handler.
+        next.ServeHTTP(w, r)
+    })
+}
+```
+
+Middlewares can be added to a router using `Router.Use()`:
+
+```go
+r := mux.NewRouter()
+r.HandleFunc("/", handler)
+r.Use(loggingMiddleware)
+```
+
+A more complex authentication middleware, which maps session token to users, could be written as:
+
+```go
+// Define our struct
+type authenticationMiddleware struct {
+	tokenUsers map[string]string
+}
+
+// Initialize it somewhere
+func (amw *authenticationMiddleware) Populate() {
+	amw.tokenUsers["00000000"] = "user0"
+	amw.tokenUsers["aaaaaaaa"] = "userA"
+	amw.tokenUsers["05f717e5"] = "randomUser"
+	amw.tokenUsers["deadbeef"] = "user0"
+}
+
+// Middleware function, which will be called for each request
+func (amw *authenticationMiddleware) Middleware(next http.Handler) http.Handler {
+    return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+        token := r.Header.Get("X-Session-Token")
+
+        if user, found := amw.tokenUsers[token]; found {
+        	// We found the token in our map
+        	log.Printf("Authenticated user %s\n", user)
+        	// Pass down the request to the next middleware (or final handler)
+        	next.ServeHTTP(w, r)
+        } else {
+        	// Write an error and stop the handler chain
+        	http.Error(w, "Forbidden", http.StatusForbidden)
+        }
+    })
+}
+```
+
+```go
+r := mux.NewRouter()
+r.HandleFunc("/", handler)
+
+amw := authenticationMiddleware{tokenUsers: make(map[string]string)}
+amw.Populate()
+
+r.Use(amw.Middleware)
+```
+
+Note: The handler chain will be stopped if your middleware doesn't call `next.ServeHTTP()` with the corresponding parameters. This can be used to abort a request if the middleware writer wants to. Middlewares _should_ write to `ResponseWriter` if they _are_ going to terminate the request, and they _should not_ write to `ResponseWriter` if they _are not_ going to terminate it.
+
+### Handling CORS Requests
+
+[CORSMethodMiddleware](https://godoc.org/github.com/gorilla/mux#CORSMethodMiddleware) intends to make it easier to strictly set the `Access-Control-Allow-Methods` response header.
+
+* You will still need to use your own CORS handler to set the other CORS headers such as `Access-Control-Allow-Origin`
+* The middleware will set the `Access-Control-Allow-Methods` header to all the method matchers (e.g. `r.Methods(http.MethodGet, http.MethodPut, http.MethodOptions)` -> `Access-Control-Allow-Methods: GET,PUT,OPTIONS`) on a route
+* If you do not specify any methods, then:
+> _Important_: there must be an `OPTIONS` method matcher for the middleware to set the headers.
+
+Here is an example of using `CORSMethodMiddleware` along with a custom `OPTIONS` handler to set all the required CORS headers:
+
+```go
+package main
+
+import (
+	"net/http"
+	"github.com/gorilla/mux"
+)
+
+func main() {
+    r := mux.NewRouter()
+
+    // IMPORTANT: you must specify an OPTIONS method matcher for the middleware to set CORS headers
+    r.HandleFunc("/foo", fooHandler).Methods(http.MethodGet, http.MethodPut, http.MethodPatch, http.MethodOptions)
+    r.Use(mux.CORSMethodMiddleware(r))
+    
+    http.ListenAndServe(":8080", r)
+}
+
+func fooHandler(w http.ResponseWriter, r *http.Request) {
+    w.Header().Set("Access-Control-Allow-Origin", "*")
+    if r.Method == http.MethodOptions {
+        return
+    }
+
+    w.Write([]byte("foo"))
+}
+```
+
+And an request to `/foo` using something like:
+
+```bash
+curl localhost:8080/foo -v
+```
+
+Would look like:
+
+```bash
+*   Trying ::1...
+* TCP_NODELAY set
+* Connected to localhost (::1) port 8080 (#0)
+> GET /foo HTTP/1.1
+> Host: localhost:8080
+> User-Agent: curl/7.59.0
+> Accept: */*
+> 
+< HTTP/1.1 200 OK
+< Access-Control-Allow-Methods: GET,PUT,PATCH,OPTIONS
+< Access-Control-Allow-Origin: *
+< Date: Fri, 28 Jun 2019 20:13:30 GMT
+< Content-Length: 3
+< Content-Type: text/plain; charset=utf-8
+< 
+* Connection #0 to host localhost left intact
+foo
+```
+
+### Testing Handlers
+
+Testing handlers in a Go web application is straightforward, and _mux_ doesn't complicate this any further. Given two files: `endpoints.go` and `endpoints_test.go`, here's how we'd test an application using _mux_.
+
+First, our simple HTTP handler:
+
+```go
+// endpoints.go
+package main
+
+func HealthCheckHandler(w http.ResponseWriter, r *http.Request) {
+    // A very simple health check.
+    w.Header().Set("Content-Type", "application/json")
+    w.WriteHeader(http.StatusOK)
+
+    // In the future we could report back on the status of our DB, or our cache
+    // (e.g. Redis) by performing a simple PING, and include them in the response.
+    io.WriteString(w, `{"alive": true}`)
+}
+
+func main() {
+    r := mux.NewRouter()
+    r.HandleFunc("/health", HealthCheckHandler)
+
+    log.Fatal(http.ListenAndServe("localhost:8080", r))
+}
+```
+
+Our test code:
+
+```go
+// endpoints_test.go
+package main
+
+import (
+    "net/http"
+    "net/http/httptest"
+    "testing"
+)
+
+func TestHealthCheckHandler(t *testing.T) {
+    // Create a request to pass to our handler. We don't have any query parameters for now, so we'll
+    // pass 'nil' as the third parameter.
+    req, err := http.NewRequest("GET", "/health", nil)
+    if err != nil {
+        t.Fatal(err)
+    }
+
+    // We create a ResponseRecorder (which satisfies http.ResponseWriter) to record the response.
+    rr := httptest.NewRecorder()
+    handler := http.HandlerFunc(HealthCheckHandler)
+
+    // Our handlers satisfy http.Handler, so we can call their ServeHTTP method
+    // directly and pass in our Request and ResponseRecorder.
+    handler.ServeHTTP(rr, req)
+
+    // Check the status code is what we expect.
+    if status := rr.Code; status != http.StatusOK {
+        t.Errorf("handler returned wrong status code: got %v want %v",
+            status, http.StatusOK)
+    }
+
+    // Check the response body is what we expect.
+    expected := `{"alive": true}`
+    if rr.Body.String() != expected {
+        t.Errorf("handler returned unexpected body: got %v want %v",
+            rr.Body.String(), expected)
+    }
+}
+```
+
+In the case that our routes have [variables](#examples), we can pass those in the request. We could write
+[table-driven tests](https://dave.cheney.net/2013/06/09/writing-table-driven-tests-in-go) to test multiple
+possible route variables as needed.
+
+```go
+// endpoints.go
+func main() {
+    r := mux.NewRouter()
+    // A route with a route variable:
+    r.HandleFunc("/metrics/{type}", MetricsHandler)
+
+    log.Fatal(http.ListenAndServe("localhost:8080", r))
+}
+```
+
+Our test file, with a table-driven test of `routeVariables`:
+
+```go
+// endpoints_test.go
+func TestMetricsHandler(t *testing.T) {
+    tt := []struct{
+        routeVariable string
+        shouldPass bool
+    }{
+        {"goroutines", true},
+        {"heap", true},
+        {"counters", true},
+        {"queries", true},
+        {"adhadaeqm3k", false},
+    }
+
+    for _, tc := range tt {
+        path := fmt.Sprintf("/metrics/%s", tc.routeVariable)
+        req, err := http.NewRequest("GET", path, nil)
+        if err != nil {
+            t.Fatal(err)
+        }
+
+        rr := httptest.NewRecorder()
+	
+	// To add the vars to the context, 
+	// we need to create a router through which we can pass the request.
+	router := mux.NewRouter()
+        router.HandleFunc("/metrics/{type}", MetricsHandler)
+        router.ServeHTTP(rr, req)
+
+        // In this case, our MetricsHandler returns a non-200 response
+        // for a route variable it doesn't know about.
+        if rr.Code == http.StatusOK && !tc.shouldPass {
+            t.Errorf("handler should have failed on routeVariable %s: got %v want %v",
+                tc.routeVariable, rr.Code, http.StatusOK)
+        }
+    }
+}
+```
+
+## Full Example
+
+Here's a complete, runnable example of a small `mux` based server:
+
+```go
+package main
+
+import (
+    "net/http"
+    "log"
+    "github.com/gorilla/mux"
+)
+
+func YourHandler(w http.ResponseWriter, r *http.Request) {
+    w.Write([]byte("Gorilla!\n"))
+}
+
+func main() {
+    r := mux.NewRouter()
+    // Routes consist of a path and a handler function.
+    r.HandleFunc("/", YourHandler)
+
+    // Bind to a port and pass our router in
+    log.Fatal(http.ListenAndServe(":8000", r))
+}
+```
+
+## License
+
+BSD licensed. See the LICENSE file for details.

vendor/github.com/gorilla/mux/doc.go

@@ -0,0 +1,305 @@
+// Copyright 2012 The Gorilla Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+/*
+Package mux implements a request router and dispatcher.
+
+The name mux stands for "HTTP request multiplexer". Like the standard
+http.ServeMux, mux.Router matches incoming requests against a list of
+registered routes and calls a handler for the route that matches the URL
+or other conditions. The main features are:
+
+  - Requests can be matched based on URL host, path, path prefix, schemes,
+    header and query values, HTTP methods or using custom matchers.
+  - URL hosts, paths and query values can have variables with an optional
+    regular expression.
+  - Registered URLs can be built, or "reversed", which helps maintaining
+    references to resources.
+  - Routes can be used as subrouters: nested routes are only tested if the
+    parent route matches. This is useful to define groups of routes that
+    share common conditions like a host, a path prefix or other repeated
+    attributes. As a bonus, this optimizes request matching.
+  - It implements the http.Handler interface so it is compatible with the
+    standard http.ServeMux.
+
+Let's start registering a couple of URL paths and handlers:
+
+	func main() {
+		r := mux.NewRouter()
+		r.HandleFunc("/", HomeHandler)
+		r.HandleFunc("/products", ProductsHandler)
+		r.HandleFunc("/articles", ArticlesHandler)
+		http.Handle("/", r)
+	}
+
+Here we register three routes mapping URL paths to handlers. This is
+equivalent to how http.HandleFunc() works: if an incoming request URL matches
+one of the paths, the corresponding handler is called passing
+(http.ResponseWriter, *http.Request) as parameters.
+
+Paths can have variables. They are defined using the format {name} or
+{name:pattern}. If a regular expression pattern is not defined, the matched
+variable will be anything until the next slash. For example:
+
+	r := mux.NewRouter()
+	r.HandleFunc("/products/{key}", ProductHandler)
+	r.HandleFunc("/articles/{category}/", ArticlesCategoryHandler)
+	r.HandleFunc("/articles/{category}/{id:[0-9]+}", ArticleHandler)
+
+Groups can be used inside patterns, as long as they are non-capturing (?:re). For example:
+
+	r.HandleFunc("/articles/{category}/{sort:(?:asc|desc|new)}", ArticlesCategoryHandler)
+
+The names are used to create a map of route variables which can be retrieved
+calling mux.Vars():
+
+	vars := mux.Vars(request)
+	category := vars["category"]
+
+Note that if any capturing groups are present, mux will panic() during parsing. To prevent
+this, convert any capturing groups to non-capturing, e.g. change "/{sort:(asc|desc)}" to
+"/{sort:(?:asc|desc)}". This is a change from prior versions which behaved unpredictably
+when capturing groups were present.
+
+And this is all you need to know about the basic usage. More advanced options
+are explained below.
+
+Routes can also be restricted to a domain or subdomain. Just define a host
+pattern to be matched. They can also have variables:
+
+	r := mux.NewRouter()
+	// Only matches if domain is "www.example.com".
+	r.Host("www.example.com")
+	// Matches a dynamic subdomain.
+	r.Host("{subdomain:[a-z]+}.domain.com")
+
+There are several other matchers that can be added. To match path prefixes:
+
+	r.PathPrefix("/products/")
+
+...or HTTP methods:
+
+	r.Methods("GET", "POST")
+
+...or URL schemes:
+
+	r.Schemes("https")
+
+...or header values:
+
+	r.Headers("X-Requested-With", "XMLHttpRequest")
+
+...or query values:
+
+	r.Queries("key", "value")
+
+...or to use a custom matcher function:
+
+	r.MatcherFunc(func(r *http.Request, rm *RouteMatch) bool {
+		return r.ProtoMajor == 0
+	})
+
+...and finally, it is possible to combine several matchers in a single route:
+
+	r.HandleFunc("/products", ProductsHandler).
+	  Host("www.example.com").
+	  Methods("GET").
+	  Schemes("http")
+
+Setting the same matching conditions again and again can be boring, so we have
+a way to group several routes that share the same requirements.
+We call it "subrouting".
+
+For example, let's say we have several URLs that should only match when the
+host is "www.example.com". Create a route for that host and get a "subrouter"
+from it:
+
+	r := mux.NewRouter()
+	s := r.Host("www.example.com").Subrouter()
+
+Then register routes in the subrouter:
+
+	s.HandleFunc("/products/", ProductsHandler)
+	s.HandleFunc("/products/{key}", ProductHandler)
+	s.HandleFunc("/articles/{category}/{id:[0-9]+}"), ArticleHandler)
+
+The three URL paths we registered above will only be tested if the domain is
+"www.example.com", because the subrouter is tested first. This is not
+only convenient, but also optimizes request matching. You can create
+subrouters combining any attribute matchers accepted by a route.
+
+Subrouters can be used to create domain or path "namespaces": you define
+subrouters in a central place and then parts of the app can register its
+paths relatively to a given subrouter.
+
+There's one more thing about subroutes. When a subrouter has a path prefix,
+the inner routes use it as base for their paths:
+
+	r := mux.NewRouter()
+	s := r.PathPrefix("/products").Subrouter()
+	// "/products/"
+	s.HandleFunc("/", ProductsHandler)
+	// "/products/{key}/"
+	s.HandleFunc("/{key}/", ProductHandler)
+	// "/products/{key}/details"
+	s.HandleFunc("/{key}/details", ProductDetailsHandler)
+
+Note that the path provided to PathPrefix() represents a "wildcard": calling
+PathPrefix("/static/").Handler(...) means that the handler will be passed any
+request that matches "/static/*". This makes it easy to serve static files with mux:
+
+	func main() {
+		var dir string
+
+		flag.StringVar(&dir, "dir", ".", "the directory to serve files from. Defaults to the current dir")
+		flag.Parse()
+		r := mux.NewRouter()
+
+		// This will serve files under http://localhost:8000/static/<filename>
+		r.PathPrefix("/static/").Handler(http.StripPrefix("/static/", http.FileServer(http.Dir(dir))))
+
+		srv := &http.Server{
+			Handler:      r,
+			Addr:         "127.0.0.1:8000",
+			// Good practice: enforce timeouts for servers you create!
+			WriteTimeout: 15 * time.Second,
+			ReadTimeout:  15 * time.Second,
+		}
+
+		log.Fatal(srv.ListenAndServe())
+	}
+
+Now let's see how to build registered URLs.
+
+Routes can be named. All routes that define a name can have their URLs built,
+or "reversed". We define a name calling Name() on a route. For example:
+
+	r := mux.NewRouter()
+	r.HandleFunc("/articles/{category}/{id:[0-9]+}", ArticleHandler).
+	  Name("article")
+
+To build a URL, get the route and call the URL() method, passing a sequence of
+key/value pairs for the route variables. For the previous route, we would do:
+
+	url, err := r.Get("article").URL("category", "technology", "id", "42")
+
+...and the result will be a url.URL with the following path:
+
+	"/articles/technology/42"
+
+This also works for host and query value variables:
+
+	r := mux.NewRouter()
+	r.Host("{subdomain}.domain.com").
+	  Path("/articles/{category}/{id:[0-9]+}").
+	  Queries("filter", "{filter}").
+	  HandlerFunc(ArticleHandler).
+	  Name("article")
+
+	// url.String() will be "http://news.domain.com/articles/technology/42?filter=gorilla"
+	url, err := r.Get("article").URL("subdomain", "news",
+	                                 "category", "technology",
+	                                 "id", "42",
+	                                 "filter", "gorilla")
+
+All variables defined in the route are required, and their values must
+conform to the corresponding patterns. These requirements guarantee that a
+generated URL will always match a registered route -- the only exception is
+for explicitly defined "build-only" routes which never match.
+
+Regex support also exists for matching Headers within a route. For example, we could do:
+
+	r.HeadersRegexp("Content-Type", "application/(text|json)")
+
+...and the route will match both requests with a Content-Type of `application/json` as well as
+`application/text`
+
+There's also a way to build only the URL host or path for a route:
+use the methods URLHost() or URLPath() instead. For the previous route,
+we would do:
+
+	// "http://news.domain.com/"
+	host, err := r.Get("article").URLHost("subdomain", "news")
+
+	// "/articles/technology/42"
+	path, err := r.Get("article").URLPath("category", "technology", "id", "42")
+
+And if you use subrouters, host and path defined separately can be built
+as well:
+
+	r := mux.NewRouter()
+	s := r.Host("{subdomain}.domain.com").Subrouter()
+	s.Path("/articles/{category}/{id:[0-9]+}").
+	  HandlerFunc(ArticleHandler).
+	  Name("article")
+
+	// "http://news.domain.com/articles/technology/42"
+	url, err := r.Get("article").URL("subdomain", "news",
+	                                 "category", "technology",
+	                                 "id", "42")
+
+Mux supports the addition of middlewares to a Router, which are executed in the order they are added if a match is found, including its subrouters. Middlewares are (typically) small pieces of code which take one request, do something with it, and pass it down to another middleware or the final handler. Some common use cases for middleware are request logging, header manipulation, or ResponseWriter hijacking.
+
+	type MiddlewareFunc func(http.Handler) http.Handler
+
+Typically, the returned handler is a closure which does something with the http.ResponseWriter and http.Request passed to it, and then calls the handler passed as parameter to the MiddlewareFunc (closures can access variables from the context where they are created).
+
+A very basic middleware which logs the URI of the request being handled could be written as:
+
+	func simpleMw(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			// Do stuff here
+			log.Println(r.RequestURI)
+			// Call the next handler, which can be another middleware in the chain, or the final handler.
+			next.ServeHTTP(w, r)
+		})
+	}
+
+Middlewares can be added to a router using `Router.Use()`:
+
+	r := mux.NewRouter()
+	r.HandleFunc("/", handler)
+	r.Use(simpleMw)
+
+A more complex authentication middleware, which maps session token to users, could be written as:
+
+	// Define our struct
+	type authenticationMiddleware struct {
+		tokenUsers map[string]string
+	}
+
+	// Initialize it somewhere
+	func (amw *authenticationMiddleware) Populate() {
+		amw.tokenUsers["00000000"] = "user0"
+		amw.tokenUsers["aaaaaaaa"] = "userA"
+		amw.tokenUsers["05f717e5"] = "randomUser"
+		amw.tokenUsers["deadbeef"] = "user0"
+	}
+
+	// Middleware function, which will be called for each request
+	func (amw *authenticationMiddleware) Middleware(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			token := r.Header.Get("X-Session-Token")
+
+			if user, found := amw.tokenUsers[token]; found {
+				// We found the token in our map
+				log.Printf("Authenticated user %s\n", user)
+				next.ServeHTTP(w, r)
+			} else {
+				http.Error(w, "Forbidden", http.StatusForbidden)
+			}
+		})
+	}
+
+	r := mux.NewRouter()
+	r.HandleFunc("/", handler)
+
+	amw := authenticationMiddleware{tokenUsers: make(map[string]string)}
+	amw.Populate()
+
+	r.Use(amw.Middleware)
+
+Note: The handler chain will be stopped if your middleware doesn't call `next.ServeHTTP()` with the corresponding parameters. This can be used to abort a request if the middleware writer wants to.
+*/
+package mux

vendor/github.com/gorilla/mux/middleware.go

@@ -0,0 +1,74 @@
+package mux
+
+import (
+	"net/http"
+	"strings"
+)
+
+// MiddlewareFunc is a function which receives an http.Handler and returns another http.Handler.
+// Typically, the returned handler is a closure which does something with the http.ResponseWriter and http.Request passed
+// to it, and then calls the handler passed as parameter to the MiddlewareFunc.
+type MiddlewareFunc func(http.Handler) http.Handler
+
+// middleware interface is anything which implements a MiddlewareFunc named Middleware.
+type middleware interface {
+	Middleware(handler http.Handler) http.Handler
+}
+
+// Middleware allows MiddlewareFunc to implement the middleware interface.
+func (mw MiddlewareFunc) Middleware(handler http.Handler) http.Handler {
+	return mw(handler)
+}
+
+// Use appends a MiddlewareFunc to the chain. Middleware can be used to intercept or otherwise modify requests and/or responses, and are executed in the order that they are applied to the Router.
+func (r *Router) Use(mwf ...MiddlewareFunc) {
+	for _, fn := range mwf {
+		r.middlewares = append(r.middlewares, fn)
+	}
+}
+
+// useInterface appends a middleware to the chain. Middleware can be used to intercept or otherwise modify requests and/or responses, and are executed in the order that they are applied to the Router.
+func (r *Router) useInterface(mw middleware) {
+	r.middlewares = append(r.middlewares, mw)
+}
+
+// CORSMethodMiddleware automatically sets the Access-Control-Allow-Methods response header
+// on requests for routes that have an OPTIONS method matcher to all the method matchers on
+// the route. Routes that do not explicitly handle OPTIONS requests will not be processed
+// by the middleware. See examples for usage.
+func CORSMethodMiddleware(r *Router) MiddlewareFunc {
+	return func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
+			allMethods, err := getAllMethodsForRoute(r, req)
+			if err == nil {
+				for _, v := range allMethods {
+					if v == http.MethodOptions {
+						w.Header().Set("Access-Control-Allow-Methods", strings.Join(allMethods, ","))
+					}
+				}
+			}
+
+			next.ServeHTTP(w, req)
+		})
+	}
+}
+
+// getAllMethodsForRoute returns all the methods from method matchers matching a given
+// request.
+func getAllMethodsForRoute(r *Router, req *http.Request) ([]string, error) {
+	var allMethods []string
+
+	for _, route := range r.routes {
+		var match RouteMatch
+		if route.Match(req, &match) || match.MatchErr == ErrMethodMismatch {
+			methods, err := route.GetMethods()
+			if err != nil {
+				return nil, err
+			}
+
+			allMethods = append(allMethods, methods...)
+		}
+	}
+
+	return allMethods, nil
+}

vendor/github.com/gorilla/mux/mux.go

@@ -0,0 +1,608 @@
+// Copyright 2012 The Gorilla Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package mux
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"net/http"
+	"path"
+	"regexp"
+)
+
+var (
+	// ErrMethodMismatch is returned when the method in the request does not match
+	// the method defined against the route.
+	ErrMethodMismatch = errors.New("method is not allowed")
+	// ErrNotFound is returned when no route match is found.
+	ErrNotFound = errors.New("no matching route was found")
+)
+
+// NewRouter returns a new router instance.
+func NewRouter() *Router {
+	return &Router{namedRoutes: make(map[string]*Route)}
+}
+
+// Router registers routes to be matched and dispatches a handler.
+//
+// It implements the http.Handler interface, so it can be registered to serve
+// requests:
+//
+//	var router = mux.NewRouter()
+//
+//	func main() {
+//	    http.Handle("/", router)
+//	}
+//
+// Or, for Google App Engine, register it in a init() function:
+//
+//	func init() {
+//	    http.Handle("/", router)
+//	}
+//
+// This will send all incoming requests to the router.
+type Router struct {
+	// Configurable Handler to be used when no route matches.
+	// This can be used to render your own 404 Not Found errors.
+	NotFoundHandler http.Handler
+
+	// Configurable Handler to be used when the request method does not match the route.
+	// This can be used to render your own 405 Method Not Allowed errors.
+	MethodNotAllowedHandler http.Handler
+
+	// Routes to be matched, in order.
+	routes []*Route
+
+	// Routes by name for URL building.
+	namedRoutes map[string]*Route
+
+	// If true, do not clear the request context after handling the request.
+	//
+	// Deprecated: No effect, since the context is stored on the request itself.
+	KeepContext bool
+
+	// Slice of middlewares to be called after a match is found
+	middlewares []middleware
+
+	// configuration shared with `Route`
+	routeConf
+}
+
+// common route configuration shared between `Router` and `Route`
+type routeConf struct {
+	// If true, "/path/foo%2Fbar/to" will match the path "/path/{var}/to"
+	useEncodedPath bool
+
+	// If true, when the path pattern is "/path/", accessing "/path" will
+	// redirect to the former and vice versa.
+	strictSlash bool
+
+	// If true, when the path pattern is "/path//to", accessing "/path//to"
+	// will not redirect
+	skipClean bool
+
+	// Manager for the variables from host and path.
+	regexp routeRegexpGroup
+
+	// List of matchers.
+	matchers []matcher
+
+	// The scheme used when building URLs.
+	buildScheme string
+
+	buildVarsFunc BuildVarsFunc
+}
+
+// returns an effective deep copy of `routeConf`
+func copyRouteConf(r routeConf) routeConf {
+	c := r
+
+	if r.regexp.path != nil {
+		c.regexp.path = copyRouteRegexp(r.regexp.path)
+	}
+
+	if r.regexp.host != nil {
+		c.regexp.host = copyRouteRegexp(r.regexp.host)
+	}
+
+	c.regexp.queries = make([]*routeRegexp, 0, len(r.regexp.queries))
+	for _, q := range r.regexp.queries {
+		c.regexp.queries = append(c.regexp.queries, copyRouteRegexp(q))
+	}
+
+	c.matchers = make([]matcher, len(r.matchers))
+	copy(c.matchers, r.matchers)
+
+	return c
+}
+
+func copyRouteRegexp(r *routeRegexp) *routeRegexp {
+	c := *r
+	return &c
+}
+
+// Match attempts to match the given request against the router's registered routes.
+//
+// If the request matches a route of this router or one of its subrouters the Route,
+// Handler, and Vars fields of the the match argument are filled and this function
+// returns true.
+//
+// If the request does not match any of this router's or its subrouters' routes
+// then this function returns false. If available, a reason for the match failure
+// will be filled in the match argument's MatchErr field. If the match failure type
+// (eg: not found) has a registered handler, the handler is assigned to the Handler
+// field of the match argument.
+func (r *Router) Match(req *http.Request, match *RouteMatch) bool {
+	for _, route := range r.routes {
+		if route.Match(req, match) {
+			// Build middleware chain if no error was found
+			if match.MatchErr == nil {
+				for i := len(r.middlewares) - 1; i >= 0; i-- {
+					match.Handler = r.middlewares[i].Middleware(match.Handler)
+				}
+			}
+			return true
+		}
+	}
+
+	if match.MatchErr == ErrMethodMismatch {
+		if r.MethodNotAllowedHandler != nil {
+			match.Handler = r.MethodNotAllowedHandler
+			return true
+		}
+
+		return false
+	}
+
+	// Closest match for a router (includes sub-routers)
+	if r.NotFoundHandler != nil {
+		match.Handler = r.NotFoundHandler
+		match.MatchErr = ErrNotFound
+		return true
+	}
+
+	match.MatchErr = ErrNotFound
+	return false
+}
+
+// ServeHTTP dispatches the handler registered in the matched route.
+//
+// When there is a match, the route variables can be retrieved calling
+// mux.Vars(request).
+func (r *Router) ServeHTTP(w http.ResponseWriter, req *http.Request) {
+	if !r.skipClean {
+		path := req.URL.Path
+		if r.useEncodedPath {
+			path = req.URL.EscapedPath()
+		}
+		// Clean path to canonical form and redirect.
+		if p := cleanPath(path); p != path {
+
+			// Added 3 lines (Philip Schlump) - It was dropping the query string and #whatever from query.
+			// This matches with fix in go 1.2 r.c. 4 for same problem.  Go Issue:
+			// http://code.google.com/p/go/issues/detail?id=5252
+			url := *req.URL
+			url.Path = p
+			p = url.String()
+
+			w.Header().Set("Location", p)
+			w.WriteHeader(http.StatusMovedPermanently)
+			return
+		}
+	}
+	var match RouteMatch
+	var handler http.Handler
+	if r.Match(req, &match) {
+		handler = match.Handler
+		req = requestWithVars(req, match.Vars)
+		req = requestWithRoute(req, match.Route)
+	}
+
+	if handler == nil && match.MatchErr == ErrMethodMismatch {
+		handler = methodNotAllowedHandler()
+	}
+
+	if handler == nil {
+		handler = http.NotFoundHandler()
+	}
+
+	handler.ServeHTTP(w, req)
+}
+
+// Get returns a route registered with the given name.
+func (r *Router) Get(name string) *Route {
+	return r.namedRoutes[name]
+}
+
+// GetRoute returns a route registered with the given name. This method
+// was renamed to Get() and remains here for backwards compatibility.
+func (r *Router) GetRoute(name string) *Route {
+	return r.namedRoutes[name]
+}
+
+// StrictSlash defines the trailing slash behavior for new routes. The initial
+// value is false.
+//
+// When true, if the route path is "/path/", accessing "/path" will perform a redirect
+// to the former and vice versa. In other words, your application will always
+// see the path as specified in the route.
+//
+// When false, if the route path is "/path", accessing "/path/" will not match
+// this route and vice versa.
+//
+// The re-direct is a HTTP 301 (Moved Permanently). Note that when this is set for
+// routes with a non-idempotent method (e.g. POST, PUT), the subsequent re-directed
+// request will be made as a GET by most clients. Use middleware or client settings
+// to modify this behaviour as needed.
+//
+// Special case: when a route sets a path prefix using the PathPrefix() method,
+// strict slash is ignored for that route because the redirect behavior can't
+// be determined from a prefix alone. However, any subrouters created from that
+// route inherit the original StrictSlash setting.
+func (r *Router) StrictSlash(value bool) *Router {
+	r.strictSlash = value
+	return r
+}
+
+// SkipClean defines the path cleaning behaviour for new routes. The initial
+// value is false. Users should be careful about which routes are not cleaned
+//
+// When true, if the route path is "/path//to", it will remain with the double
+// slash. This is helpful if you have a route like: /fetch/http://xkcd.com/534/
+//
+// When false, the path will be cleaned, so /fetch/http://xkcd.com/534/ will
+// become /fetch/http/xkcd.com/534
+func (r *Router) SkipClean(value bool) *Router {
+	r.skipClean = value
+	return r
+}
+
+// UseEncodedPath tells the router to match the encoded original path
+// to the routes.
+// For eg. "/path/foo%2Fbar/to" will match the path "/path/{var}/to".
+//
+// If not called, the router will match the unencoded path to the routes.
+// For eg. "/path/foo%2Fbar/to" will match the path "/path/foo/bar/to"
+func (r *Router) UseEncodedPath() *Router {
+	r.useEncodedPath = true
+	return r
+}
+
+// ----------------------------------------------------------------------------
+// Route factories
+// ----------------------------------------------------------------------------
+
+// NewRoute registers an empty route.
+func (r *Router) NewRoute() *Route {
+	// initialize a route with a copy of the parent router's configuration
+	route := &Route{routeConf: copyRouteConf(r.routeConf), namedRoutes: r.namedRoutes}
+	r.routes = append(r.routes, route)
+	return route
+}
+
+// Name registers a new route with a name.
+// See Route.Name().
+func (r *Router) Name(name string) *Route {
+	return r.NewRoute().Name(name)
+}
+
+// Handle registers a new route with a matcher for the URL path.
+// See Route.Path() and Route.Handler().
+func (r *Router) Handle(path string, handler http.Handler) *Route {
+	return r.NewRoute().Path(path).Handler(handler)
+}
+
+// HandleFunc registers a new route with a matcher for the URL path.
+// See Route.Path() and Route.HandlerFunc().
+func (r *Router) HandleFunc(path string, f func(http.ResponseWriter,
+	*http.Request)) *Route {
+	return r.NewRoute().Path(path).HandlerFunc(f)
+}
+
+// Headers registers a new route with a matcher for request header values.
+// See Route.Headers().
+func (r *Router) Headers(pairs ...string) *Route {
+	return r.NewRoute().Headers(pairs...)
+}
+
+// Host registers a new route with a matcher for the URL host.
+// See Route.Host().
+func (r *Router) Host(tpl string) *Route {
+	return r.NewRoute().Host(tpl)
+}
+
+// MatcherFunc registers a new route with a custom matcher function.
+// See Route.MatcherFunc().
+func (r *Router) MatcherFunc(f MatcherFunc) *Route {
+	return r.NewRoute().MatcherFunc(f)
+}
+
+// Methods registers a new route with a matcher for HTTP methods.
+// See Route.Methods().
+func (r *Router) Methods(methods ...string) *Route {
+	return r.NewRoute().Methods(methods...)
+}
+
+// Path registers a new route with a matcher for the URL path.
+// See Route.Path().
+func (r *Router) Path(tpl string) *Route {
+	return r.NewRoute().Path(tpl)
+}
+
+// PathPrefix registers a new route with a matcher for the URL path prefix.
+// See Route.PathPrefix().
+func (r *Router) PathPrefix(tpl string) *Route {
+	return r.NewRoute().PathPrefix(tpl)
+}
+
+// Queries registers a new route with a matcher for URL query values.
+// See Route.Queries().
+func (r *Router) Queries(pairs ...string) *Route {
+	return r.NewRoute().Queries(pairs...)
+}
+
+// Schemes registers a new route with a matcher for URL schemes.
+// See Route.Schemes().
+func (r *Router) Schemes(schemes ...string) *Route {
+	return r.NewRoute().Schemes(schemes...)
+}
+
+// BuildVarsFunc registers a new route with a custom function for modifying
+// route variables before building a URL.
+func (r *Router) BuildVarsFunc(f BuildVarsFunc) *Route {
+	return r.NewRoute().BuildVarsFunc(f)
+}
+
+// Walk walks the router and all its sub-routers, calling walkFn for each route
+// in the tree. The routes are walked in the order they were added. Sub-routers
+// are explored depth-first.
+func (r *Router) Walk(walkFn WalkFunc) error {
+	return r.walk(walkFn, []*Route{})
+}
+
+// SkipRouter is used as a return value from WalkFuncs to indicate that the
+// router that walk is about to descend down to should be skipped.
+var SkipRouter = errors.New("skip this router")
+
+// WalkFunc is the type of the function called for each route visited by Walk.
+// At every invocation, it is given the current route, and the current router,
+// and a list of ancestor routes that lead to the current route.
+type WalkFunc func(route *Route, router *Router, ancestors []*Route) error
+
+func (r *Router) walk(walkFn WalkFunc, ancestors []*Route) error {
+	for _, t := range r.routes {
+		err := walkFn(t, r, ancestors)
+		if err == SkipRouter {
+			continue
+		}
+		if err != nil {
+			return err
+		}
+		for _, sr := range t.matchers {
+			if h, ok := sr.(*Router); ok {
+				ancestors = append(ancestors, t)
+				err := h.walk(walkFn, ancestors)
+				if err != nil {
+					return err
+				}
+				ancestors = ancestors[:len(ancestors)-1]
+			}
+		}
+		if h, ok := t.handler.(*Router); ok {
+			ancestors = append(ancestors, t)
+			err := h.walk(walkFn, ancestors)
+			if err != nil {
+				return err
+			}
+			ancestors = ancestors[:len(ancestors)-1]
+		}
+	}
+	return nil
+}
+
+// ----------------------------------------------------------------------------
+// Context
+// ----------------------------------------------------------------------------
+
+// RouteMatch stores information about a matched route.
+type RouteMatch struct {
+	Route   *Route
+	Handler http.Handler
+	Vars    map[string]string
+
+	// MatchErr is set to appropriate matching error
+	// It is set to ErrMethodMismatch if there is a mismatch in
+	// the request method and route method
+	MatchErr error
+}
+
+type contextKey int
+
+const (
+	varsKey contextKey = iota
+	routeKey
+)
+
+// Vars returns the route variables for the current request, if any.
+func Vars(r *http.Request) map[string]string {
+	if rv := r.Context().Value(varsKey); rv != nil {
+		return rv.(map[string]string)
+	}
+	return nil
+}
+
+// CurrentRoute returns the matched route for the current request, if any.
+// This only works when called inside the handler of the matched route
+// because the matched route is stored in the request context which is cleared
+// after the handler returns.
+func CurrentRoute(r *http.Request) *Route {
+	if rv := r.Context().Value(routeKey); rv != nil {
+		return rv.(*Route)
+	}
+	return nil
+}
+
+func requestWithVars(r *http.Request, vars map[string]string) *http.Request {
+	ctx := context.WithValue(r.Context(), varsKey, vars)
+	return r.WithContext(ctx)
+}
+
+func requestWithRoute(r *http.Request, route *Route) *http.Request {
+	ctx := context.WithValue(r.Context(), routeKey, route)
+	return r.WithContext(ctx)
+}
+
+// ----------------------------------------------------------------------------
+// Helpers
+// ----------------------------------------------------------------------------
+
+// cleanPath returns the canonical path for p, eliminating . and .. elements.
+// Borrowed from the net/http package.
+func cleanPath(p string) string {
+	if p == "" {
+		return "/"
+	}
+	if p[0] != '/' {
+		p = "/" + p
+	}
+	np := path.Clean(p)
+	// path.Clean removes trailing slash except for root;
+	// put the trailing slash back if necessary.
+	if p[len(p)-1] == '/' && np != "/" {
+		np += "/"
+	}
+
+	return np
+}
+
+// uniqueVars returns an error if two slices contain duplicated strings.
+func uniqueVars(s1, s2 []string) error {
+	for _, v1 := range s1 {
+		for _, v2 := range s2 {
+			if v1 == v2 {
+				return fmt.Errorf("mux: duplicated route variable %q", v2)
+			}
+		}
+	}
+	return nil
+}
+
+// checkPairs returns the count of strings passed in, and an error if
+// the count is not an even number.
+func checkPairs(pairs ...string) (int, error) {
+	length := len(pairs)
+	if length%2 != 0 {
+		return length, fmt.Errorf(
+			"mux: number of parameters must be multiple of 2, got %v", pairs)
+	}
+	return length, nil
+}
+
+// mapFromPairsToString converts variadic string parameters to a
+// string to string map.
+func mapFromPairsToString(pairs ...string) (map[string]string, error) {
+	length, err := checkPairs(pairs...)
+	if err != nil {
+		return nil, err
+	}
+	m := make(map[string]string, length/2)
+	for i := 0; i < length; i += 2 {
+		m[pairs[i]] = pairs[i+1]
+	}
+	return m, nil
+}
+
+// mapFromPairsToRegex converts variadic string parameters to a
+// string to regex map.
+func mapFromPairsToRegex(pairs ...string) (map[string]*regexp.Regexp, error) {
+	length, err := checkPairs(pairs...)
+	if err != nil {
+		return nil, err
+	}
+	m := make(map[string]*regexp.Regexp, length/2)
+	for i := 0; i < length; i += 2 {
+		regex, err := regexp.Compile(pairs[i+1])
+		if err != nil {
+			return nil, err
+		}
+		m[pairs[i]] = regex
+	}
+	return m, nil
+}
+
+// matchInArray returns true if the given string value is in the array.
+func matchInArray(arr []string, value string) bool {
+	for _, v := range arr {
+		if v == value {
+			return true
+		}
+	}
+	return false
+}
+
+// matchMapWithString returns true if the given key/value pairs exist in a given map.
+func matchMapWithString(toCheck map[string]string, toMatch map[string][]string, canonicalKey bool) bool {
+	for k, v := range toCheck {
+		// Check if key exists.
+		if canonicalKey {
+			k = http.CanonicalHeaderKey(k)
+		}
+		if values := toMatch[k]; values == nil {
+			return false
+		} else if v != "" {
+			// If value was defined as an empty string we only check that the
+			// key exists. Otherwise we also check for equality.
+			valueExists := false
+			for _, value := range values {
+				if v == value {
+					valueExists = true
+					break
+				}
+			}
+			if !valueExists {
+				return false
+			}
+		}
+	}
+	return true
+}
+
+// matchMapWithRegex returns true if the given key/value pairs exist in a given map compiled against
+// the given regex
+func matchMapWithRegex(toCheck map[string]*regexp.Regexp, toMatch map[string][]string, canonicalKey bool) bool {
+	for k, v := range toCheck {
+		// Check if key exists.
+		if canonicalKey {
+			k = http.CanonicalHeaderKey(k)
+		}
+		if values := toMatch[k]; values == nil {
+			return false
+		} else if v != nil {
+			// If value was defined as an empty string we only check that the
+			// key exists. Otherwise we also check for equality.
+			valueExists := false
+			for _, value := range values {
+				if v.MatchString(value) {
+					valueExists = true
+					break
+				}
+			}
+			if !valueExists {
+				return false
+			}
+		}
+	}
+	return true
+}
+
+// methodNotAllowed replies to the request with an HTTP status code 405.
+func methodNotAllowed(w http.ResponseWriter, r *http.Request) {
+	w.WriteHeader(http.StatusMethodNotAllowed)
+}
+
+// methodNotAllowedHandler returns a simple request handler
+// that replies to each request with a status code 405.
+func methodNotAllowedHandler() http.Handler { return http.HandlerFunc(methodNotAllowed) }

vendor/github.com/gorilla/mux/regexp.go

@@ -0,0 +1,388 @@
+// Copyright 2012 The Gorilla Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package mux
+
+import (
+	"bytes"
+	"fmt"
+	"net/http"
+	"net/url"
+	"regexp"
+	"strconv"
+	"strings"
+)
+
+type routeRegexpOptions struct {
+	strictSlash    bool
+	useEncodedPath bool
+}
+
+type regexpType int
+
+const (
+	regexpTypePath regexpType = iota
+	regexpTypeHost
+	regexpTypePrefix
+	regexpTypeQuery
+)
+
+// newRouteRegexp parses a route template and returns a routeRegexp,
+// used to match a host, a path or a query string.
+//
+// It will extract named variables, assemble a regexp to be matched, create
+// a "reverse" template to build URLs and compile regexps to validate variable
+// values used in URL building.
+//
+// Previously we accepted only Python-like identifiers for variable
+// names ([a-zA-Z_][a-zA-Z0-9_]*), but currently the only restriction is that
+// name and pattern can't be empty, and names can't contain a colon.
+func newRouteRegexp(tpl string, typ regexpType, options routeRegexpOptions) (*routeRegexp, error) {
+	// Check if it is well-formed.
+	idxs, errBraces := braceIndices(tpl)
+	if errBraces != nil {
+		return nil, errBraces
+	}
+	// Backup the original.
+	template := tpl
+	// Now let's parse it.
+	defaultPattern := "[^/]+"
+	if typ == regexpTypeQuery {
+		defaultPattern = ".*"
+	} else if typ == regexpTypeHost {
+		defaultPattern = "[^.]+"
+	}
+	// Only match strict slash if not matching
+	if typ != regexpTypePath {
+		options.strictSlash = false
+	}
+	// Set a flag for strictSlash.
+	endSlash := false
+	if options.strictSlash && strings.HasSuffix(tpl, "/") {
+		tpl = tpl[:len(tpl)-1]
+		endSlash = true
+	}
+	varsN := make([]string, len(idxs)/2)
+	varsR := make([]*regexp.Regexp, len(idxs)/2)
+	pattern := bytes.NewBufferString("")
+	pattern.WriteByte('^')
+	reverse := bytes.NewBufferString("")
+	var end int
+	var err error
+	for i := 0; i < len(idxs); i += 2 {
+		// Set all values we are interested in.
+		raw := tpl[end:idxs[i]]
+		end = idxs[i+1]
+		parts := strings.SplitN(tpl[idxs[i]+1:end-1], ":", 2)
+		name := parts[0]
+		patt := defaultPattern
+		if len(parts) == 2 {
+			patt = parts[1]
+		}
+		// Name or pattern can't be empty.
+		if name == "" || patt == "" {
+			return nil, fmt.Errorf("mux: missing name or pattern in %q",
+				tpl[idxs[i]:end])
+		}
+		// Build the regexp pattern.
+		fmt.Fprintf(pattern, "%s(?P<%s>%s)", regexp.QuoteMeta(raw), varGroupName(i/2), patt)
+
+		// Build the reverse template.
+		fmt.Fprintf(reverse, "%s%%s", raw)
+
+		// Append variable name and compiled pattern.
+		varsN[i/2] = name
+		varsR[i/2], err = regexp.Compile(fmt.Sprintf("^%s$", patt))
+		if err != nil {
+			return nil, err
+		}
+	}
+	// Add the remaining.
+	raw := tpl[end:]
+	pattern.WriteString(regexp.QuoteMeta(raw))
+	if options.strictSlash {
+		pattern.WriteString("[/]?")
+	}
+	if typ == regexpTypeQuery {
+		// Add the default pattern if the query value is empty
+		if queryVal := strings.SplitN(template, "=", 2)[1]; queryVal == "" {
+			pattern.WriteString(defaultPattern)
+		}
+	}
+	if typ != regexpTypePrefix {
+		pattern.WriteByte('$')
+	}
+
+	var wildcardHostPort bool
+	if typ == regexpTypeHost {
+		if !strings.Contains(pattern.String(), ":") {
+			wildcardHostPort = true
+		}
+	}
+	reverse.WriteString(raw)
+	if endSlash {
+		reverse.WriteByte('/')
+	}
+	// Compile full regexp.
+	reg, errCompile := regexp.Compile(pattern.String())
+	if errCompile != nil {
+		return nil, errCompile
+	}
+
+	// Check for capturing groups which used to work in older versions
+	if reg.NumSubexp() != len(idxs)/2 {
+		panic(fmt.Sprintf("route %s contains capture groups in its regexp. ", template) +
+			"Only non-capturing groups are accepted: e.g. (?:pattern) instead of (pattern)")
+	}
+
+	// Done!
+	return &routeRegexp{
+		template:         template,
+		regexpType:       typ,
+		options:          options,
+		regexp:           reg,
+		reverse:          reverse.String(),
+		varsN:            varsN,
+		varsR:            varsR,
+		wildcardHostPort: wildcardHostPort,
+	}, nil
+}
+
+// routeRegexp stores a regexp to match a host or path and information to
+// collect and validate route variables.
+type routeRegexp struct {
+	// The unmodified template.
+	template string
+	// The type of match
+	regexpType regexpType
+	// Options for matching
+	options routeRegexpOptions
+	// Expanded regexp.
+	regexp *regexp.Regexp
+	// Reverse template.
+	reverse string
+	// Variable names.
+	varsN []string
+	// Variable regexps (validators).
+	varsR []*regexp.Regexp
+	// Wildcard host-port (no strict port match in hostname)
+	wildcardHostPort bool
+}
+
+// Match matches the regexp against the URL host or path.
+func (r *routeRegexp) Match(req *http.Request, match *RouteMatch) bool {
+	if r.regexpType == regexpTypeHost {
+		host := getHost(req)
+		if r.wildcardHostPort {
+			// Don't be strict on the port match
+			if i := strings.Index(host, ":"); i != -1 {
+				host = host[:i]
+			}
+		}
+		return r.regexp.MatchString(host)
+	}
+
+	if r.regexpType == regexpTypeQuery {
+		return r.matchQueryString(req)
+	}
+	path := req.URL.Path
+	if r.options.useEncodedPath {
+		path = req.URL.EscapedPath()
+	}
+	return r.regexp.MatchString(path)
+}
+
+// url builds a URL part using the given values.
+func (r *routeRegexp) url(values map[string]string) (string, error) {
+	urlValues := make([]interface{}, len(r.varsN))
+	for k, v := range r.varsN {
+		value, ok := values[v]
+		if !ok {
+			return "", fmt.Errorf("mux: missing route variable %q", v)
+		}
+		if r.regexpType == regexpTypeQuery {
+			value = url.QueryEscape(value)
+		}
+		urlValues[k] = value
+	}
+	rv := fmt.Sprintf(r.reverse, urlValues...)
+	if !r.regexp.MatchString(rv) {
+		// The URL is checked against the full regexp, instead of checking
+		// individual variables. This is faster but to provide a good error
+		// message, we check individual regexps if the URL doesn't match.
+		for k, v := range r.varsN {
+			if !r.varsR[k].MatchString(values[v]) {
+				return "", fmt.Errorf(
+					"mux: variable %q doesn't match, expected %q", values[v],
+					r.varsR[k].String())
+			}
+		}
+	}
+	return rv, nil
+}
+
+// getURLQuery returns a single query parameter from a request URL.
+// For a URL with foo=bar&baz=ding, we return only the relevant key
+// value pair for the routeRegexp.
+func (r *routeRegexp) getURLQuery(req *http.Request) string {
+	if r.regexpType != regexpTypeQuery {
+		return ""
+	}
+	templateKey := strings.SplitN(r.template, "=", 2)[0]
+	val, ok := findFirstQueryKey(req.URL.RawQuery, templateKey)
+	if ok {
+		return templateKey + "=" + val
+	}
+	return ""
+}
+
+// findFirstQueryKey returns the same result as (*url.URL).Query()[key][0].
+// If key was not found, empty string and false is returned.
+func findFirstQueryKey(rawQuery, key string) (value string, ok bool) {
+	query := []byte(rawQuery)
+	for len(query) > 0 {
+		foundKey := query
+		if i := bytes.IndexAny(foundKey, "&;"); i >= 0 {
+			foundKey, query = foundKey[:i], foundKey[i+1:]
+		} else {
+			query = query[:0]
+		}
+		if len(foundKey) == 0 {
+			continue
+		}
+		var value []byte
+		if i := bytes.IndexByte(foundKey, '='); i >= 0 {
+			foundKey, value = foundKey[:i], foundKey[i+1:]
+		}
+		if len(foundKey) < len(key) {
+			// Cannot possibly be key.
+			continue
+		}
+		keyString, err := url.QueryUnescape(string(foundKey))
+		if err != nil {
+			continue
+		}
+		if keyString != key {
+			continue
+		}
+		valueString, err := url.QueryUnescape(string(value))
+		if err != nil {
+			continue
+		}
+		return valueString, true
+	}
+	return "", false
+}
+
+func (r *routeRegexp) matchQueryString(req *http.Request) bool {
+	return r.regexp.MatchString(r.getURLQuery(req))
+}
+
+// braceIndices returns the first level curly brace indices from a string.
+// It returns an error in case of unbalanced braces.
+func braceIndices(s string) ([]int, error) {
+	var level, idx int
+	var idxs []int
+	for i := 0; i < len(s); i++ {
+		switch s[i] {
+		case '{':
+			if level++; level == 1 {
+				idx = i
+			}
+		case '}':
+			if level--; level == 0 {
+				idxs = append(idxs, idx, i+1)
+			} else if level < 0 {
+				return nil, fmt.Errorf("mux: unbalanced braces in %q", s)
+			}
+		}
+	}
+	if level != 0 {
+		return nil, fmt.Errorf("mux: unbalanced braces in %q", s)
+	}
+	return idxs, nil
+}
+
+// varGroupName builds a capturing group name for the indexed variable.
+func varGroupName(idx int) string {
+	return "v" + strconv.Itoa(idx)
+}
+
+// ----------------------------------------------------------------------------
+// routeRegexpGroup
+// ----------------------------------------------------------------------------
+
+// routeRegexpGroup groups the route matchers that carry variables.
+type routeRegexpGroup struct {
+	host    *routeRegexp
+	path    *routeRegexp
+	queries []*routeRegexp
+}
+
+// setMatch extracts the variables from the URL once a route matches.
+func (v routeRegexpGroup) setMatch(req *http.Request, m *RouteMatch, r *Route) {
+	// Store host variables.
+	if v.host != nil {
+		host := getHost(req)
+		if v.host.wildcardHostPort {
+			// Don't be strict on the port match
+			if i := strings.Index(host, ":"); i != -1 {
+				host = host[:i]
+			}
+		}
+		matches := v.host.regexp.FindStringSubmatchIndex(host)
+		if len(matches) > 0 {
+			extractVars(host, matches, v.host.varsN, m.Vars)
+		}
+	}
+	path := req.URL.Path
+	if r.useEncodedPath {
+		path = req.URL.EscapedPath()
+	}
+	// Store path variables.
+	if v.path != nil {
+		matches := v.path.regexp.FindStringSubmatchIndex(path)
+		if len(matches) > 0 {
+			extractVars(path, matches, v.path.varsN, m.Vars)
+			// Check if we should redirect.
+			if v.path.options.strictSlash {
+				p1 := strings.HasSuffix(path, "/")
+				p2 := strings.HasSuffix(v.path.template, "/")
+				if p1 != p2 {
+					u, _ := url.Parse(req.URL.String())
+					if p1 {
+						u.Path = u.Path[:len(u.Path)-1]
+					} else {
+						u.Path += "/"
+					}
+					m.Handler = http.RedirectHandler(u.String(), http.StatusMovedPermanently)
+				}
+			}
+		}
+	}
+	// Store query string variables.
+	for _, q := range v.queries {
+		queryURL := q.getURLQuery(req)
+		matches := q.regexp.FindStringSubmatchIndex(queryURL)
+		if len(matches) > 0 {
+			extractVars(queryURL, matches, q.varsN, m.Vars)
+		}
+	}
+}
+
+// getHost tries its best to return the request host.
+// According to section 14.23 of RFC 2616 the Host header
+// can include the port number if the default value of 80 is not used.
+func getHost(r *http.Request) string {
+	if r.URL.IsAbs() {
+		return r.URL.Host
+	}
+	return r.Host
+}
+
+func extractVars(input string, matches []int, names []string, output map[string]string) {
+	for i, name := range names {
+		output[name] = input[matches[2*i+2]:matches[2*i+3]]
+	}
+}

vendor/github.com/gorilla/mux/route.go

@@ -0,0 +1,765 @@
+// Copyright 2012 The Gorilla Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package mux
+
+import (
+	"errors"
+	"fmt"
+	"net/http"
+	"net/url"
+	"regexp"
+	"strings"
+)
+
+// Route stores information to match a request and build URLs.
+type Route struct {
+	// Request handler for the route.
+	handler http.Handler
+	// If true, this route never matches: it is only used to build URLs.
+	buildOnly bool
+	// The name used to build URLs.
+	name string
+	// Error resulted from building a route.
+	err error
+
+	// "global" reference to all named routes
+	namedRoutes map[string]*Route
+
+	// config possibly passed in from `Router`
+	routeConf
+}
+
+// SkipClean reports whether path cleaning is enabled for this route via
+// Router.SkipClean.
+func (r *Route) SkipClean() bool {
+	return r.skipClean
+}
+
+// Match matches the route against the request.
+func (r *Route) Match(req *http.Request, match *RouteMatch) bool {
+	if r.buildOnly || r.err != nil {
+		return false
+	}
+
+	var matchErr error
+
+	// Match everything.
+	for _, m := range r.matchers {
+		if matched := m.Match(req, match); !matched {
+			if _, ok := m.(methodMatcher); ok {
+				matchErr = ErrMethodMismatch
+				continue
+			}
+
+			// Ignore ErrNotFound errors. These errors arise from match call
+			// to Subrouters.
+			//
+			// This prevents subsequent matching subrouters from failing to
+			// run middleware. If not ignored, the middleware would see a
+			// non-nil MatchErr and be skipped, even when there was a
+			// matching route.
+			if match.MatchErr == ErrNotFound {
+				match.MatchErr = nil
+			}
+
+			matchErr = nil // nolint:ineffassign
+			return false
+		} else {
+			// Multiple routes may share the same path but use different HTTP methods. For instance:
+			// Route 1: POST "/users/{id}".
+			// Route 2: GET "/users/{id}", parameters: "id": "[0-9]+".
+			//
+			// The router must handle these cases correctly. For a GET request to "/users/abc" with "id" as "-2",
+			// The router should return a "Not Found" error as no route fully matches this request.
+			if match.MatchErr == ErrMethodMismatch {
+				match.MatchErr = nil
+			}
+		}
+	}
+
+	if matchErr != nil {
+		match.MatchErr = matchErr
+		return false
+	}
+
+	if match.MatchErr == ErrMethodMismatch && r.handler != nil {
+		// We found a route which matches request method, clear MatchErr
+		match.MatchErr = nil
+		// Then override the mis-matched handler
+		match.Handler = r.handler
+	}
+
+	// Yay, we have a match. Let's collect some info about it.
+	if match.Route == nil {
+		match.Route = r
+	}
+	if match.Handler == nil {
+		match.Handler = r.handler
+	}
+	if match.Vars == nil {
+		match.Vars = make(map[string]string)
+	}
+
+	// Set variables.
+	r.regexp.setMatch(req, match, r)
+	return true
+}
+
+// ----------------------------------------------------------------------------
+// Route attributes
+// ----------------------------------------------------------------------------
+
+// GetError returns an error resulted from building the route, if any.
+func (r *Route) GetError() error {
+	return r.err
+}
+
+// BuildOnly sets the route to never match: it is only used to build URLs.
+func (r *Route) BuildOnly() *Route {
+	r.buildOnly = true
+	return r
+}
+
+// Handler --------------------------------------------------------------------
+
+// Handler sets a handler for the route.
+func (r *Route) Handler(handler http.Handler) *Route {
+	if r.err == nil {
+		r.handler = handler
+	}
+	return r
+}
+
+// HandlerFunc sets a handler function for the route.
+func (r *Route) HandlerFunc(f func(http.ResponseWriter, *http.Request)) *Route {
+	return r.Handler(http.HandlerFunc(f))
+}
+
+// GetHandler returns the handler for the route, if any.
+func (r *Route) GetHandler() http.Handler {
+	return r.handler
+}
+
+// Name -----------------------------------------------------------------------
+
+// Name sets the name for the route, used to build URLs.
+// It is an error to call Name more than once on a route.
+func (r *Route) Name(name string) *Route {
+	if r.name != "" {
+		r.err = fmt.Errorf("mux: route already has name %q, can't set %q",
+			r.name, name)
+	}
+	if r.err == nil {
+		r.name = name
+		r.namedRoutes[name] = r
+	}
+	return r
+}
+
+// GetName returns the name for the route, if any.
+func (r *Route) GetName() string {
+	return r.name
+}
+
+// ----------------------------------------------------------------------------
+// Matchers
+// ----------------------------------------------------------------------------
+
+// matcher types try to match a request.
+type matcher interface {
+	Match(*http.Request, *RouteMatch) bool
+}
+
+// addMatcher adds a matcher to the route.
+func (r *Route) addMatcher(m matcher) *Route {
+	if r.err == nil {
+		r.matchers = append(r.matchers, m)
+	}
+	return r
+}
+
+// addRegexpMatcher adds a host or path matcher and builder to a route.
+func (r *Route) addRegexpMatcher(tpl string, typ regexpType) error {
+	if r.err != nil {
+		return r.err
+	}
+	if typ == regexpTypePath || typ == regexpTypePrefix {
+		if len(tpl) > 0 && tpl[0] != '/' {
+			return fmt.Errorf("mux: path must start with a slash, got %q", tpl)
+		}
+		if r.regexp.path != nil {
+			tpl = strings.TrimRight(r.regexp.path.template, "/") + tpl
+		}
+	}
+	rr, err := newRouteRegexp(tpl, typ, routeRegexpOptions{
+		strictSlash:    r.strictSlash,
+		useEncodedPath: r.useEncodedPath,
+	})
+	if err != nil {
+		return err
+	}
+	for _, q := range r.regexp.queries {
+		if err = uniqueVars(rr.varsN, q.varsN); err != nil {
+			return err
+		}
+	}
+	if typ == regexpTypeHost {
+		if r.regexp.path != nil {
+			if err = uniqueVars(rr.varsN, r.regexp.path.varsN); err != nil {
+				return err
+			}
+		}
+		r.regexp.host = rr
+	} else {
+		if r.regexp.host != nil {
+			if err = uniqueVars(rr.varsN, r.regexp.host.varsN); err != nil {
+				return err
+			}
+		}
+		if typ == regexpTypeQuery {
+			r.regexp.queries = append(r.regexp.queries, rr)
+		} else {
+			r.regexp.path = rr
+		}
+	}
+	r.addMatcher(rr)
+	return nil
+}
+
+// Headers --------------------------------------------------------------------
+
+// headerMatcher matches the request against header values.
+type headerMatcher map[string]string
+
+func (m headerMatcher) Match(r *http.Request, match *RouteMatch) bool {
+	return matchMapWithString(m, r.Header, true)
+}
+
+// Headers adds a matcher for request header values.
+// It accepts a sequence of key/value pairs to be matched. For example:
+//
+//	r := mux.NewRouter().NewRoute()
+//	r.Headers("Content-Type", "application/json",
+//	          "X-Requested-With", "XMLHttpRequest")
+//
+// The above route will only match if both request header values match.
+// If the value is an empty string, it will match any value if the key is set.
+func (r *Route) Headers(pairs ...string) *Route {
+	if r.err == nil {
+		var headers map[string]string
+		headers, r.err = mapFromPairsToString(pairs...)
+		return r.addMatcher(headerMatcher(headers))
+	}
+	return r
+}
+
+// headerRegexMatcher matches the request against the route given a regex for the header
+type headerRegexMatcher map[string]*regexp.Regexp
+
+func (m headerRegexMatcher) Match(r *http.Request, match *RouteMatch) bool {
+	return matchMapWithRegex(m, r.Header, true)
+}
+
+// HeadersRegexp accepts a sequence of key/value pairs, where the value has regex
+// support. For example:
+//
+//	r := mux.NewRouter().NewRoute()
+//	r.HeadersRegexp("Content-Type", "application/(text|json)",
+//	          "X-Requested-With", "XMLHttpRequest")
+//
+// The above route will only match if both the request header matches both regular expressions.
+// If the value is an empty string, it will match any value if the key is set.
+// Use the start and end of string anchors (^ and $) to match an exact value.
+func (r *Route) HeadersRegexp(pairs ...string) *Route {
+	if r.err == nil {
+		var headers map[string]*regexp.Regexp
+		headers, r.err = mapFromPairsToRegex(pairs...)
+		return r.addMatcher(headerRegexMatcher(headers))
+	}
+	return r
+}
+
+// Host -----------------------------------------------------------------------
+
+// Host adds a matcher for the URL host.
+// It accepts a template with zero or more URL variables enclosed by {}.
+// Variables can define an optional regexp pattern to be matched:
+//
+// - {name} matches anything until the next dot.
+//
+// - {name:pattern} matches the given regexp pattern.
+//
+// For example:
+//
+//	r := mux.NewRouter().NewRoute()
+//	r.Host("www.example.com")
+//	r.Host("{subdomain}.domain.com")
+//	r.Host("{subdomain:[a-z]+}.domain.com")
+//
+// Variable names must be unique in a given route. They can be retrieved
+// calling mux.Vars(request).
+func (r *Route) Host(tpl string) *Route {
+	r.err = r.addRegexpMatcher(tpl, regexpTypeHost)
+	return r
+}
+
+// MatcherFunc ----------------------------------------------------------------
+
+// MatcherFunc is the function signature used by custom matchers.
+type MatcherFunc func(*http.Request, *RouteMatch) bool
+
+// Match returns the match for a given request.
+func (m MatcherFunc) Match(r *http.Request, match *RouteMatch) bool {
+	return m(r, match)
+}
+
+// MatcherFunc adds a custom function to be used as request matcher.
+func (r *Route) MatcherFunc(f MatcherFunc) *Route {
+	return r.addMatcher(f)
+}
+
+// Methods --------------------------------------------------------------------
+
+// methodMatcher matches the request against HTTP methods.
+type methodMatcher []string
+
+func (m methodMatcher) Match(r *http.Request, match *RouteMatch) bool {
+	return matchInArray(m, r.Method)
+}
+
+// Methods adds a matcher for HTTP methods.
+// It accepts a sequence of one or more methods to be matched, e.g.:
+// "GET", "POST", "PUT".
+func (r *Route) Methods(methods ...string) *Route {
+	for k, v := range methods {
+		methods[k] = strings.ToUpper(v)
+	}
+	return r.addMatcher(methodMatcher(methods))
+}
+
+// Path -----------------------------------------------------------------------
+
+// Path adds a matcher for the URL path.
+// It accepts a template with zero or more URL variables enclosed by {}. The
+// template must start with a "/".
+// Variables can define an optional regexp pattern to be matched:
+//
+// - {name} matches anything until the next slash.
+//
+// - {name:pattern} matches the given regexp pattern.
+//
+// For example:
+//
+//	r := mux.NewRouter().NewRoute()
+//	r.Path("/products/").Handler(ProductsHandler)
+//	r.Path("/products/{key}").Handler(ProductsHandler)
+//	r.Path("/articles/{category}/{id:[0-9]+}").
+//	  Handler(ArticleHandler)
+//
+// Variable names must be unique in a given route. They can be retrieved
+// calling mux.Vars(request).
+func (r *Route) Path(tpl string) *Route {
+	r.err = r.addRegexpMatcher(tpl, regexpTypePath)
+	return r
+}
+
+// PathPrefix -----------------------------------------------------------------
+
+// PathPrefix adds a matcher for the URL path prefix. This matches if the given
+// template is a prefix of the full URL path. See Route.Path() for details on
+// the tpl argument.
+//
+// Note that it does not treat slashes specially ("/foobar/" will be matched by
+// the prefix "/foo") so you may want to use a trailing slash here.
+//
+// Also note that the setting of Router.StrictSlash() has no effect on routes
+// with a PathPrefix matcher.
+func (r *Route) PathPrefix(tpl string) *Route {
+	r.err = r.addRegexpMatcher(tpl, regexpTypePrefix)
+	return r
+}
+
+// Query ----------------------------------------------------------------------
+
+// Queries adds a matcher for URL query values.
+// It accepts a sequence of key/value pairs. Values may define variables.
+// For example:
+//
+//	r := mux.NewRouter().NewRoute()
+//	r.Queries("foo", "bar", "id", "{id:[0-9]+}")
+//
+// The above route will only match if the URL contains the defined queries
+// values, e.g.: ?foo=bar&id=42.
+//
+// If the value is an empty string, it will match any value if the key is set.
+//
+// Variables can define an optional regexp pattern to be matched:
+//
+// - {name} matches anything until the next slash.
+//
+// - {name:pattern} matches the given regexp pattern.
+func (r *Route) Queries(pairs ...string) *Route {
+	length := len(pairs)
+	if length%2 != 0 {
+		r.err = fmt.Errorf(
+			"mux: number of parameters must be multiple of 2, got %v", pairs)
+		return nil
+	}
+	for i := 0; i < length; i += 2 {
+		if r.err = r.addRegexpMatcher(pairs[i]+"="+pairs[i+1], regexpTypeQuery); r.err != nil {
+			return r
+		}
+	}
+
+	return r
+}
+
+// Schemes --------------------------------------------------------------------
+
+// schemeMatcher matches the request against URL schemes.
+type schemeMatcher []string
+
+func (m schemeMatcher) Match(r *http.Request, match *RouteMatch) bool {
+	scheme := r.URL.Scheme
+	// https://golang.org/pkg/net/http/#Request
+	// "For [most] server requests, fields other than Path and RawQuery will be
+	// empty."
+	// Since we're an http muxer, the scheme is either going to be http or https
+	// though, so we can just set it based on the tls termination state.
+	if scheme == "" {
+		if r.TLS == nil {
+			scheme = "http"
+		} else {
+			scheme = "https"
+		}
+	}
+	return matchInArray(m, scheme)
+}
+
+// Schemes adds a matcher for URL schemes.
+// It accepts a sequence of schemes to be matched, e.g.: "http", "https".
+// If the request's URL has a scheme set, it will be matched against.
+// Generally, the URL scheme will only be set if a previous handler set it,
+// such as the ProxyHeaders handler from gorilla/handlers.
+// If unset, the scheme will be determined based on the request's TLS
+// termination state.
+// The first argument to Schemes will be used when constructing a route URL.
+func (r *Route) Schemes(schemes ...string) *Route {
+	for k, v := range schemes {
+		schemes[k] = strings.ToLower(v)
+	}
+	if len(schemes) > 0 {
+		r.buildScheme = schemes[0]
+	}
+	return r.addMatcher(schemeMatcher(schemes))
+}
+
+// BuildVarsFunc --------------------------------------------------------------
+
+// BuildVarsFunc is the function signature used by custom build variable
+// functions (which can modify route variables before a route's URL is built).
+type BuildVarsFunc func(map[string]string) map[string]string
+
+// BuildVarsFunc adds a custom function to be used to modify build variables
+// before a route's URL is built.
+func (r *Route) BuildVarsFunc(f BuildVarsFunc) *Route {
+	if r.buildVarsFunc != nil {
+		// compose the old and new functions
+		old := r.buildVarsFunc
+		r.buildVarsFunc = func(m map[string]string) map[string]string {
+			return f(old(m))
+		}
+	} else {
+		r.buildVarsFunc = f
+	}
+	return r
+}
+
+// Subrouter ------------------------------------------------------------------
+
+// Subrouter creates a subrouter for the route.
+//
+// It will test the inner routes only if the parent route matched. For example:
+//
+//	r := mux.NewRouter().NewRoute()
+//	s := r.Host("www.example.com").Subrouter()
+//	s.HandleFunc("/products/", ProductsHandler)
+//	s.HandleFunc("/products/{key}", ProductHandler)
+//	s.HandleFunc("/articles/{category}/{id:[0-9]+}"), ArticleHandler)
+//
+// Here, the routes registered in the subrouter won't be tested if the host
+// doesn't match.
+func (r *Route) Subrouter() *Router {
+	// initialize a subrouter with a copy of the parent route's configuration
+	router := &Router{routeConf: copyRouteConf(r.routeConf), namedRoutes: r.namedRoutes}
+	r.addMatcher(router)
+	return router
+}
+
+// ----------------------------------------------------------------------------
+// URL building
+// ----------------------------------------------------------------------------
+
+// URL builds a URL for the route.
+//
+// It accepts a sequence of key/value pairs for the route variables. For
+// example, given this route:
+//
+//	r := mux.NewRouter()
+//	r.HandleFunc("/articles/{category}/{id:[0-9]+}", ArticleHandler).
+//	  Name("article")
+//
+// ...a URL for it can be built using:
+//
+//	url, err := r.Get("article").URL("category", "technology", "id", "42")
+//
+// ...which will return an url.URL with the following path:
+//
+//	"/articles/technology/42"
+//
+// This also works for host variables:
+//
+//	r := mux.NewRouter()
+//	r.HandleFunc("/articles/{category}/{id:[0-9]+}", ArticleHandler).
+//	  Host("{subdomain}.domain.com").
+//	  Name("article")
+//
+//	// url.String() will be "http://news.domain.com/articles/technology/42"
+//	url, err := r.Get("article").URL("subdomain", "news",
+//	                                 "category", "technology",
+//	                                 "id", "42")
+//
+// The scheme of the resulting url will be the first argument that was passed to Schemes:
+//
+//	// url.String() will be "https://example.com"
+//	r := mux.NewRouter().NewRoute()
+//	url, err := r.Host("example.com")
+//	             .Schemes("https", "http").URL()
+//
+// All variables defined in the route are required, and their values must
+// conform to the corresponding patterns.
+func (r *Route) URL(pairs ...string) (*url.URL, error) {
+	if r.err != nil {
+		return nil, r.err
+	}
+	values, err := r.prepareVars(pairs...)
+	if err != nil {
+		return nil, err
+	}
+	var scheme, host, path string
+	queries := make([]string, 0, len(r.regexp.queries))
+	if r.regexp.host != nil {
+		if host, err = r.regexp.host.url(values); err != nil {
+			return nil, err
+		}
+		scheme = "http"
+		if r.buildScheme != "" {
+			scheme = r.buildScheme
+		}
+	}
+	if r.regexp.path != nil {
+		if path, err = r.regexp.path.url(values); err != nil {
+			return nil, err
+		}
+	}
+	for _, q := range r.regexp.queries {
+		var query string
+		if query, err = q.url(values); err != nil {
+			return nil, err
+		}
+		queries = append(queries, query)
+	}
+	return &url.URL{
+		Scheme:   scheme,
+		Host:     host,
+		Path:     path,
+		RawQuery: strings.Join(queries, "&"),
+	}, nil
+}
+
+// URLHost builds the host part of the URL for a route. See Route.URL().
+//
+// The route must have a host defined.
+func (r *Route) URLHost(pairs ...string) (*url.URL, error) {
+	if r.err != nil {
+		return nil, r.err
+	}
+	if r.regexp.host == nil {
+		return nil, errors.New("mux: route doesn't have a host")
+	}
+	values, err := r.prepareVars(pairs...)
+	if err != nil {
+		return nil, err
+	}
+	host, err := r.regexp.host.url(values)
+	if err != nil {
+		return nil, err
+	}
+	u := &url.URL{
+		Scheme: "http",
+		Host:   host,
+	}
+	if r.buildScheme != "" {
+		u.Scheme = r.buildScheme
+	}
+	return u, nil
+}
+
+// URLPath builds the path part of the URL for a route. See Route.URL().
+//
+// The route must have a path defined.
+func (r *Route) URLPath(pairs ...string) (*url.URL, error) {
+	if r.err != nil {
+		return nil, r.err
+	}
+	if r.regexp.path == nil {
+		return nil, errors.New("mux: route doesn't have a path")
+	}
+	values, err := r.prepareVars(pairs...)
+	if err != nil {
+		return nil, err
+	}
+	path, err := r.regexp.path.url(values)
+	if err != nil {
+		return nil, err
+	}
+	return &url.URL{
+		Path: path,
+	}, nil
+}
+
+// GetPathTemplate returns the template used to build the
+// route match.
+// This is useful for building simple REST API documentation and for instrumentation
+// against third-party services.
+// An error will be returned if the route does not define a path.
+func (r *Route) GetPathTemplate() (string, error) {
+	if r.err != nil {
+		return "", r.err
+	}
+	if r.regexp.path == nil {
+		return "", errors.New("mux: route doesn't have a path")
+	}
+	return r.regexp.path.template, nil
+}
+
+// GetPathRegexp returns the expanded regular expression used to match route path.
+// This is useful for building simple REST API documentation and for instrumentation
+// against third-party services.
+// An error will be returned if the route does not define a path.
+func (r *Route) GetPathRegexp() (string, error) {
+	if r.err != nil {
+		return "", r.err
+	}
+	if r.regexp.path == nil {
+		return "", errors.New("mux: route does not have a path")
+	}
+	return r.regexp.path.regexp.String(), nil
+}
+
+// GetQueriesRegexp returns the expanded regular expressions used to match the
+// route queries.
+// This is useful for building simple REST API documentation and for instrumentation
+// against third-party services.
+// An error will be returned if the route does not have queries.
+func (r *Route) GetQueriesRegexp() ([]string, error) {
+	if r.err != nil {
+		return nil, r.err
+	}
+	if r.regexp.queries == nil {
+		return nil, errors.New("mux: route doesn't have queries")
+	}
+	queries := make([]string, 0, len(r.regexp.queries))
+	for _, query := range r.regexp.queries {
+		queries = append(queries, query.regexp.String())
+	}
+	return queries, nil
+}
+
+// GetQueriesTemplates returns the templates used to build the
+// query matching.
+// This is useful for building simple REST API documentation and for instrumentation
+// against third-party services.
+// An error will be returned if the route does not define queries.
+func (r *Route) GetQueriesTemplates() ([]string, error) {
+	if r.err != nil {
+		return nil, r.err
+	}
+	if r.regexp.queries == nil {
+		return nil, errors.New("mux: route doesn't have queries")
+	}
+	queries := make([]string, 0, len(r.regexp.queries))
+	for _, query := range r.regexp.queries {
+		queries = append(queries, query.template)
+	}
+	return queries, nil
+}
+
+// GetMethods returns the methods the route matches against
+// This is useful for building simple REST API documentation and for instrumentation
+// against third-party services.
+// An error will be returned if route does not have methods.
+func (r *Route) GetMethods() ([]string, error) {
+	if r.err != nil {
+		return nil, r.err
+	}
+	for _, m := range r.matchers {
+		if methods, ok := m.(methodMatcher); ok {
+			return []string(methods), nil
+		}
+	}
+	return nil, errors.New("mux: route doesn't have methods")
+}
+
+// GetHostTemplate returns the template used to build the
+// route match.
+// This is useful for building simple REST API documentation and for instrumentation
+// against third-party services.
+// An error will be returned if the route does not define a host.
+func (r *Route) GetHostTemplate() (string, error) {
+	if r.err != nil {
+		return "", r.err
+	}
+	if r.regexp.host == nil {
+		return "", errors.New("mux: route doesn't have a host")
+	}
+	return r.regexp.host.template, nil
+}
+
+// GetVarNames returns the names of all variables added by regexp matchers
+// These can be used to know which route variables should be passed into r.URL()
+func (r *Route) GetVarNames() ([]string, error) {
+	if r.err != nil {
+		return nil, r.err
+	}
+	var varNames []string
+	if r.regexp.host != nil {
+		varNames = append(varNames, r.regexp.host.varsN...)
+	}
+	if r.regexp.path != nil {
+		varNames = append(varNames, r.regexp.path.varsN...)
+	}
+	for _, regx := range r.regexp.queries {
+		varNames = append(varNames, regx.varsN...)
+	}
+	return varNames, nil
+}
+
+// prepareVars converts the route variable pairs into a map. If the route has a
+// BuildVarsFunc, it is invoked.
+func (r *Route) prepareVars(pairs ...string) (map[string]string, error) {
+	m, err := mapFromPairsToString(pairs...)
+	if err != nil {
+		return nil, err
+	}
+	return r.buildVars(m), nil
+}
+
+func (r *Route) buildVars(m map[string]string) map[string]string {
+	if r.buildVarsFunc != nil {
+		m = r.buildVarsFunc(m)
+	}
+	return m
+}

vendor/github.com/gorilla/mux/test_helpers.go

@@ -0,0 +1,19 @@
+// Copyright 2012 The Gorilla Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package mux
+
+import "net/http"
+
+// SetURLVars sets the URL variables for the given request, to be accessed via
+// mux.Vars for testing route behaviour. Arguments are not modified, a shallow
+// copy is returned.
+//
+// This API should only be used for testing purposes; it provides a way to
+// inject variables into the request context. Alternatively, URL variables
+// can be set by making a route that captures the required variables,
+// starting a server and sending the request to that server.
+func SetURLVars(r *http.Request, val map[string]string) *http.Request {
+	return requestWithVars(r, val)
+}

vendor/github.com/lib/pq/.gitignore

@@ -0,0 +1,6 @@
+.db
+*.test
+*~
+*.swp
+.idea
+.vscode

vendor/github.com/lib/pq/LICENSE.md

@@ -0,0 +1,8 @@
+Copyright (c) 2011-2013, 'pq' Contributors
+Portions Copyright (C) 2011 Blake Mizerany
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

vendor/github.com/lib/pq/README.md

@@ -0,0 +1,36 @@
+# pq - A pure Go postgres driver for Go's database/sql package
+
+[![GoDoc](https://godoc.org/github.com/lib/pq?status.svg)](https://pkg.go.dev/github.com/lib/pq?tab=doc)
+
+## Install
+
+	go get github.com/lib/pq
+
+## Features
+
+* SSL
+* Handles bad connections for `database/sql`
+* Scan `time.Time` correctly (i.e. `timestamp[tz]`, `time[tz]`, `date`)
+* Scan binary blobs correctly (i.e. `bytea`)
+* Package for `hstore` support
+* COPY FROM support
+* pq.ParseURL for converting urls to connection strings for sql.Open.
+* Many libpq compatible environment variables
+* Unix socket support
+* Notifications: `LISTEN`/`NOTIFY`
+* pgpass support
+* GSS (Kerberos) auth
+
+## Tests
+
+`go test` is used for testing.  See [TESTS.md](TESTS.md) for more details.
+
+## Status
+
+This package is currently in maintenance mode, which means:
+1.   It generally does not accept new features.
+2.   It does accept bug fixes and version compatability changes provided by the community.
+3.   Maintainers usually do not resolve reported issues.
+4.   Community members are encouraged to help each other with reported issues.
+
+For users that require new features or reliable resolution of reported bugs, we recommend using [pgx](https://github.com/jackc/pgx) which is under active development.

vendor/github.com/lib/pq/TESTS.md

@@ -0,0 +1,33 @@
+# Tests
+
+## Running Tests
+
+`go test` is used for testing. A running PostgreSQL
+server is required, with the ability to log in. The
+database to connect to test with is "pqgotest," on
+"localhost" but these can be overridden using [environment
+variables](https://www.postgresql.org/docs/9.3/static/libpq-envars.html).
+
+Example:
+
+	PGHOST=/run/postgresql go test
+
+## Benchmarks
+
+A benchmark suite can be run as part of the tests:
+
+	go test -bench .
+
+## Example setup (Docker)
+
+Run a postgres container:
+
+```
+docker run --expose 5432:5432 postgres
+```
+
+Run tests:
+
+```
+PGHOST=localhost PGPORT=5432 PGUSER=postgres PGSSLMODE=disable PGDATABASE=postgres go test
+```

vendor/github.com/lib/pq/array.go

@@ -0,0 +1,895 @@
+package pq
+
+import (
+	"bytes"
+	"database/sql"
+	"database/sql/driver"
+	"encoding/hex"
+	"fmt"
+	"reflect"
+	"strconv"
+	"strings"
+)
+
+var typeByteSlice = reflect.TypeOf([]byte{})
+var typeDriverValuer = reflect.TypeOf((*driver.Valuer)(nil)).Elem()
+var typeSQLScanner = reflect.TypeOf((*sql.Scanner)(nil)).Elem()
+
+// Array returns the optimal driver.Valuer and sql.Scanner for an array or
+// slice of any dimension.
+//
+// For example:
+//  db.Query(`SELECT * FROM t WHERE id = ANY($1)`, pq.Array([]int{235, 401}))
+//
+//  var x []sql.NullInt64
+//  db.QueryRow(`SELECT ARRAY[235, 401]`).Scan(pq.Array(&x))
+//
+// Scanning multi-dimensional arrays is not supported.  Arrays where the lower
+// bound is not one (such as `[0:0]={1}') are not supported.
+func Array(a interface{}) interface {
+	driver.Valuer
+	sql.Scanner
+} {
+	switch a := a.(type) {
+	case []bool:
+		return (*BoolArray)(&a)
+	case []float64:
+		return (*Float64Array)(&a)
+	case []float32:
+		return (*Float32Array)(&a)
+	case []int64:
+		return (*Int64Array)(&a)
+	case []int32:
+		return (*Int32Array)(&a)
+	case []string:
+		return (*StringArray)(&a)
+	case [][]byte:
+		return (*ByteaArray)(&a)
+
+	case *[]bool:
+		return (*BoolArray)(a)
+	case *[]float64:
+		return (*Float64Array)(a)
+	case *[]float32:
+		return (*Float32Array)(a)
+	case *[]int64:
+		return (*Int64Array)(a)
+	case *[]int32:
+		return (*Int32Array)(a)
+	case *[]string:
+		return (*StringArray)(a)
+	case *[][]byte:
+		return (*ByteaArray)(a)
+	}
+
+	return GenericArray{a}
+}
+
+// ArrayDelimiter may be optionally implemented by driver.Valuer or sql.Scanner
+// to override the array delimiter used by GenericArray.
+type ArrayDelimiter interface {
+	// ArrayDelimiter returns the delimiter character(s) for this element's type.
+	ArrayDelimiter() string
+}
+
+// BoolArray represents a one-dimensional array of the PostgreSQL boolean type.
+type BoolArray []bool
+
+// Scan implements the sql.Scanner interface.
+func (a *BoolArray) Scan(src interface{}) error {
+	switch src := src.(type) {
+	case []byte:
+		return a.scanBytes(src)
+	case string:
+		return a.scanBytes([]byte(src))
+	case nil:
+		*a = nil
+		return nil
+	}
+
+	return fmt.Errorf("pq: cannot convert %T to BoolArray", src)
+}
+
+func (a *BoolArray) scanBytes(src []byte) error {
+	elems, err := scanLinearArray(src, []byte{','}, "BoolArray")
+	if err != nil {
+		return err
+	}
+	if *a != nil && len(elems) == 0 {
+		*a = (*a)[:0]
+	} else {
+		b := make(BoolArray, len(elems))
+		for i, v := range elems {
+			if len(v) != 1 {
+				return fmt.Errorf("pq: could not parse boolean array index %d: invalid boolean %q", i, v)
+			}
+			switch v[0] {
+			case 't':
+				b[i] = true
+			case 'f':
+				b[i] = false
+			default:
+				return fmt.Errorf("pq: could not parse boolean array index %d: invalid boolean %q", i, v)
+			}
+		}
+		*a = b
+	}
+	return nil
+}
+
+// Value implements the driver.Valuer interface.
+func (a BoolArray) Value() (driver.Value, error) {
+	if a == nil {
+		return nil, nil
+	}
+
+	if n := len(a); n > 0 {
+		// There will be exactly two curly brackets, N bytes of values,
+		// and N-1 bytes of delimiters.
+		b := make([]byte, 1+2*n)
+
+		for i := 0; i < n; i++ {
+			b[2*i] = ','
+			if a[i] {
+				b[1+2*i] = 't'
+			} else {
+				b[1+2*i] = 'f'
+			}
+		}
+
+		b[0] = '{'
+		b[2*n] = '}'
+
+		return string(b), nil
+	}
+
+	return "{}", nil
+}
+
+// ByteaArray represents a one-dimensional array of the PostgreSQL bytea type.
+type ByteaArray [][]byte
+
+// Scan implements the sql.Scanner interface.
+func (a *ByteaArray) Scan(src interface{}) error {
+	switch src := src.(type) {
+	case []byte:
+		return a.scanBytes(src)
+	case string:
+		return a.scanBytes([]byte(src))
+	case nil:
+		*a = nil
+		return nil
+	}
+
+	return fmt.Errorf("pq: cannot convert %T to ByteaArray", src)
+}
+
+func (a *ByteaArray) scanBytes(src []byte) error {
+	elems, err := scanLinearArray(src, []byte{','}, "ByteaArray")
+	if err != nil {
+		return err
+	}
+	if *a != nil && len(elems) == 0 {
+		*a = (*a)[:0]
+	} else {
+		b := make(ByteaArray, len(elems))
+		for i, v := range elems {
+			b[i], err = parseBytea(v)
+			if err != nil {
+				return fmt.Errorf("could not parse bytea array index %d: %s", i, err.Error())
+			}
+		}
+		*a = b
+	}
+	return nil
+}
+
+// Value implements the driver.Valuer interface. It uses the "hex" format which
+// is only supported on PostgreSQL 9.0 or newer.
+func (a ByteaArray) Value() (driver.Value, error) {
+	if a == nil {
+		return nil, nil
+	}
+
+	if n := len(a); n > 0 {
+		// There will be at least two curly brackets, 2*N bytes of quotes,
+		// 3*N bytes of hex formatting, and N-1 bytes of delimiters.
+		size := 1 + 6*n
+		for _, x := range a {
+			size += hex.EncodedLen(len(x))
+		}
+
+		b := make([]byte, size)
+
+		for i, s := 0, b; i < n; i++ {
+			o := copy(s, `,"\\x`)
+			o += hex.Encode(s[o:], a[i])
+			s[o] = '"'
+			s = s[o+1:]
+		}
+
+		b[0] = '{'
+		b[size-1] = '}'
+
+		return string(b), nil
+	}
+
+	return "{}", nil
+}
+
+// Float64Array represents a one-dimensional array of the PostgreSQL double
+// precision type.
+type Float64Array []float64
+
+// Scan implements the sql.Scanner interface.
+func (a *Float64Array) Scan(src interface{}) error {
+	switch src := src.(type) {
+	case []byte:
+		return a.scanBytes(src)
+	case string:
+		return a.scanBytes([]byte(src))
+	case nil:
+		*a = nil
+		return nil
+	}
+
+	return fmt.Errorf("pq: cannot convert %T to Float64Array", src)
+}
+
+func (a *Float64Array) scanBytes(src []byte) error {
+	elems, err := scanLinearArray(src, []byte{','}, "Float64Array")
+	if err != nil {
+		return err
+	}
+	if *a != nil && len(elems) == 0 {
+		*a = (*a)[:0]
+	} else {
+		b := make(Float64Array, len(elems))
+		for i, v := range elems {
+			if b[i], err = strconv.ParseFloat(string(v), 64); err != nil {
+				return fmt.Errorf("pq: parsing array element index %d: %v", i, err)
+			}
+		}
+		*a = b
+	}
+	return nil
+}
+
+// Value implements the driver.Valuer interface.
+func (a Float64Array) Value() (driver.Value, error) {
+	if a == nil {
+		return nil, nil
+	}
+
+	if n := len(a); n > 0 {
+		// There will be at least two curly brackets, N bytes of values,
+		// and N-1 bytes of delimiters.
+		b := make([]byte, 1, 1+2*n)
+		b[0] = '{'
+
+		b = strconv.AppendFloat(b, a[0], 'f', -1, 64)
+		for i := 1; i < n; i++ {
+			b = append(b, ',')
+			b = strconv.AppendFloat(b, a[i], 'f', -1, 64)
+		}
+
+		return string(append(b, '}')), nil
+	}
+
+	return "{}", nil
+}
+
+// Float32Array represents a one-dimensional array of the PostgreSQL double
+// precision type.
+type Float32Array []float32
+
+// Scan implements the sql.Scanner interface.
+func (a *Float32Array) Scan(src interface{}) error {
+	switch src := src.(type) {
+	case []byte:
+		return a.scanBytes(src)
+	case string:
+		return a.scanBytes([]byte(src))
+	case nil:
+		*a = nil
+		return nil
+	}
+
+	return fmt.Errorf("pq: cannot convert %T to Float32Array", src)
+}
+
+func (a *Float32Array) scanBytes(src []byte) error {
+	elems, err := scanLinearArray(src, []byte{','}, "Float32Array")
+	if err != nil {
+		return err
+	}
+	if *a != nil && len(elems) == 0 {
+		*a = (*a)[:0]
+	} else {
+		b := make(Float32Array, len(elems))
+		for i, v := range elems {
+			var x float64
+			if x, err = strconv.ParseFloat(string(v), 32); err != nil {
+				return fmt.Errorf("pq: parsing array element index %d: %v", i, err)
+			}
+			b[i] = float32(x)
+		}
+		*a = b
+	}
+	return nil
+}
+
+// Value implements the driver.Valuer interface.
+func (a Float32Array) Value() (driver.Value, error) {
+	if a == nil {
+		return nil, nil
+	}
+
+	if n := len(a); n > 0 {
+		// There will be at least two curly brackets, N bytes of values,
+		// and N-1 bytes of delimiters.
+		b := make([]byte, 1, 1+2*n)
+		b[0] = '{'
+
+		b = strconv.AppendFloat(b, float64(a[0]), 'f', -1, 32)
+		for i := 1; i < n; i++ {
+			b = append(b, ',')
+			b = strconv.AppendFloat(b, float64(a[i]), 'f', -1, 32)
+		}
+
+		return string(append(b, '}')), nil
+	}
+
+	return "{}", nil
+}
+
+// GenericArray implements the driver.Valuer and sql.Scanner interfaces for
+// an array or slice of any dimension.
+type GenericArray struct{ A interface{} }
+
+func (GenericArray) evaluateDestination(rt reflect.Type) (reflect.Type, func([]byte, reflect.Value) error, string) {
+	var assign func([]byte, reflect.Value) error
+	var del = ","
+
+	// TODO calculate the assign function for other types
+	// TODO repeat this section on the element type of arrays or slices (multidimensional)
+	{
+		if reflect.PtrTo(rt).Implements(typeSQLScanner) {
+			// dest is always addressable because it is an element of a slice.
+			assign = func(src []byte, dest reflect.Value) (err error) {
+				ss := dest.Addr().Interface().(sql.Scanner)
+				if src == nil {
+					err = ss.Scan(nil)
+				} else {
+					err = ss.Scan(src)
+				}
+				return
+			}
+			goto FoundType
+		}
+
+		assign = func([]byte, reflect.Value) error {
+			return fmt.Errorf("pq: scanning to %s is not implemented; only sql.Scanner", rt)
+		}
+	}
+
+FoundType:
+
+	if ad, ok := reflect.Zero(rt).Interface().(ArrayDelimiter); ok {
+		del = ad.ArrayDelimiter()
+	}
+
+	return rt, assign, del
+}
+
+// Scan implements the sql.Scanner interface.
+func (a GenericArray) Scan(src interface{}) error {
+	dpv := reflect.ValueOf(a.A)
+	switch {
+	case dpv.Kind() != reflect.Ptr:
+		return fmt.Errorf("pq: destination %T is not a pointer to array or slice", a.A)
+	case dpv.IsNil():
+		return fmt.Errorf("pq: destination %T is nil", a.A)
+	}
+
+	dv := dpv.Elem()
+	switch dv.Kind() {
+	case reflect.Slice:
+	case reflect.Array:
+	default:
+		return fmt.Errorf("pq: destination %T is not a pointer to array or slice", a.A)
+	}
+
+	switch src := src.(type) {
+	case []byte:
+		return a.scanBytes(src, dv)
+	case string:
+		return a.scanBytes([]byte(src), dv)
+	case nil:
+		if dv.Kind() == reflect.Slice {
+			dv.Set(reflect.Zero(dv.Type()))
+			return nil
+		}
+	}
+
+	return fmt.Errorf("pq: cannot convert %T to %s", src, dv.Type())
+}
+
+func (a GenericArray) scanBytes(src []byte, dv reflect.Value) error {
+	dtype, assign, del := a.evaluateDestination(dv.Type().Elem())
+	dims, elems, err := parseArray(src, []byte(del))
+	if err != nil {
+		return err
+	}
+
+	// TODO allow multidimensional
+
+	if len(dims) > 1 {
+		return fmt.Errorf("pq: scanning from multidimensional ARRAY%s is not implemented",
+			strings.Replace(fmt.Sprint(dims), " ", "][", -1))
+	}
+
+	// Treat a zero-dimensional array like an array with a single dimension of zero.
+	if len(dims) == 0 {
+		dims = append(dims, 0)
+	}
+
+	for i, rt := 0, dv.Type(); i < len(dims); i, rt = i+1, rt.Elem() {
+		switch rt.Kind() {
+		case reflect.Slice:
+		case reflect.Array:
+			if rt.Len() != dims[i] {
+				return fmt.Errorf("pq: cannot convert ARRAY%s to %s",
+					strings.Replace(fmt.Sprint(dims), " ", "][", -1), dv.Type())
+			}
+		default:
+			// TODO handle multidimensional
+		}
+	}
+
+	values := reflect.MakeSlice(reflect.SliceOf(dtype), len(elems), len(elems))
+	for i, e := range elems {
+		if err := assign(e, values.Index(i)); err != nil {
+			return fmt.Errorf("pq: parsing array element index %d: %v", i, err)
+		}
+	}
+
+	// TODO handle multidimensional
+
+	switch dv.Kind() {
+	case reflect.Slice:
+		dv.Set(values.Slice(0, dims[0]))
+	case reflect.Array:
+		for i := 0; i < dims[0]; i++ {
+			dv.Index(i).Set(values.Index(i))
+		}
+	}
+
+	return nil
+}
+
+// Value implements the driver.Valuer interface.
+func (a GenericArray) Value() (driver.Value, error) {
+	if a.A == nil {
+		return nil, nil
+	}
+
+	rv := reflect.ValueOf(a.A)
+
+	switch rv.Kind() {
+	case reflect.Slice:
+		if rv.IsNil() {
+			return nil, nil
+		}
+	case reflect.Array:
+	default:
+		return nil, fmt.Errorf("pq: Unable to convert %T to array", a.A)
+	}
+
+	if n := rv.Len(); n > 0 {
+		// There will be at least two curly brackets, N bytes of values,
+		// and N-1 bytes of delimiters.
+		b := make([]byte, 0, 1+2*n)
+
+		b, _, err := appendArray(b, rv, n)
+		return string(b), err
+	}
+
+	return "{}", nil
+}
+
+// Int64Array represents a one-dimensional array of the PostgreSQL integer types.
+type Int64Array []int64
+
+// Scan implements the sql.Scanner interface.
+func (a *Int64Array) Scan(src interface{}) error {
+	switch src := src.(type) {
+	case []byte:
+		return a.scanBytes(src)
+	case string:
+		return a.scanBytes([]byte(src))
+	case nil:
+		*a = nil
+		return nil
+	}
+
+	return fmt.Errorf("pq: cannot convert %T to Int64Array", src)
+}
+
+func (a *Int64Array) scanBytes(src []byte) error {
+	elems, err := scanLinearArray(src, []byte{','}, "Int64Array")
+	if err != nil {
+		return err
+	}
+	if *a != nil && len(elems) == 0 {
+		*a = (*a)[:0]
+	} else {
+		b := make(Int64Array, len(elems))
+		for i, v := range elems {
+			if b[i], err = strconv.ParseInt(string(v), 10, 64); err != nil {
+				return fmt.Errorf("pq: parsing array element index %d: %v", i, err)
+			}
+		}
+		*a = b
+	}
+	return nil
+}
+
+// Value implements the driver.Valuer interface.
+func (a Int64Array) Value() (driver.Value, error) {
+	if a == nil {
+		return nil, nil
+	}
+
+	if n := len(a); n > 0 {
+		// There will be at least two curly brackets, N bytes of values,
+		// and N-1 bytes of delimiters.
+		b := make([]byte, 1, 1+2*n)
+		b[0] = '{'
+
+		b = strconv.AppendInt(b, a[0], 10)
+		for i := 1; i < n; i++ {
+			b = append(b, ',')
+			b = strconv.AppendInt(b, a[i], 10)
+		}
+
+		return string(append(b, '}')), nil
+	}
+
+	return "{}", nil
+}
+
+// Int32Array represents a one-dimensional array of the PostgreSQL integer types.
+type Int32Array []int32
+
+// Scan implements the sql.Scanner interface.
+func (a *Int32Array) Scan(src interface{}) error {
+	switch src := src.(type) {
+	case []byte:
+		return a.scanBytes(src)
+	case string:
+		return a.scanBytes([]byte(src))
+	case nil:
+		*a = nil
+		return nil
+	}
+
+	return fmt.Errorf("pq: cannot convert %T to Int32Array", src)
+}
+
+func (a *Int32Array) scanBytes(src []byte) error {
+	elems, err := scanLinearArray(src, []byte{','}, "Int32Array")
+	if err != nil {
+		return err
+	}
+	if *a != nil && len(elems) == 0 {
+		*a = (*a)[:0]
+	} else {
+		b := make(Int32Array, len(elems))
+		for i, v := range elems {
+			x, err := strconv.ParseInt(string(v), 10, 32)
+			if err != nil {
+				return fmt.Errorf("pq: parsing array element index %d: %v", i, err)
+			}
+			b[i] = int32(x)
+		}
+		*a = b
+	}
+	return nil
+}
+
+// Value implements the driver.Valuer interface.
+func (a Int32Array) Value() (driver.Value, error) {
+	if a == nil {
+		return nil, nil
+	}
+
+	if n := len(a); n > 0 {
+		// There will be at least two curly brackets, N bytes of values,
+		// and N-1 bytes of delimiters.
+		b := make([]byte, 1, 1+2*n)
+		b[0] = '{'
+
+		b = strconv.AppendInt(b, int64(a[0]), 10)
+		for i := 1; i < n; i++ {
+			b = append(b, ',')
+			b = strconv.AppendInt(b, int64(a[i]), 10)
+		}
+
+		return string(append(b, '}')), nil
+	}
+
+	return "{}", nil
+}
+
+// StringArray represents a one-dimensional array of the PostgreSQL character types.
+type StringArray []string
+
+// Scan implements the sql.Scanner interface.
+func (a *StringArray) Scan(src interface{}) error {
+	switch src := src.(type) {
+	case []byte:
+		return a.scanBytes(src)
+	case string:
+		return a.scanBytes([]byte(src))
+	case nil:
+		*a = nil
+		return nil
+	}
+
+	return fmt.Errorf("pq: cannot convert %T to StringArray", src)
+}
+
+func (a *StringArray) scanBytes(src []byte) error {
+	elems, err := scanLinearArray(src, []byte{','}, "StringArray")
+	if err != nil {
+		return err
+	}
+	if *a != nil && len(elems) == 0 {
+		*a = (*a)[:0]
+	} else {
+		b := make(StringArray, len(elems))
+		for i, v := range elems {
+			if b[i] = string(v); v == nil {
+				return fmt.Errorf("pq: parsing array element index %d: cannot convert nil to string", i)
+			}
+		}
+		*a = b
+	}
+	return nil
+}
+
+// Value implements the driver.Valuer interface.
+func (a StringArray) Value() (driver.Value, error) {
+	if a == nil {
+		return nil, nil
+	}
+
+	if n := len(a); n > 0 {
+		// There will be at least two curly brackets, 2*N bytes of quotes,
+		// and N-1 bytes of delimiters.
+		b := make([]byte, 1, 1+3*n)
+		b[0] = '{'
+
+		b = appendArrayQuotedBytes(b, []byte(a[0]))
+		for i := 1; i < n; i++ {
+			b = append(b, ',')
+			b = appendArrayQuotedBytes(b, []byte(a[i]))
+		}
+
+		return string(append(b, '}')), nil
+	}
+
+	return "{}", nil
+}
+
+// appendArray appends rv to the buffer, returning the extended buffer and
+// the delimiter used between elements.
+//
+// It panics when n <= 0 or rv's Kind is not reflect.Array nor reflect.Slice.
+func appendArray(b []byte, rv reflect.Value, n int) ([]byte, string, error) {
+	var del string
+	var err error
+
+	b = append(b, '{')
+
+	if b, del, err = appendArrayElement(b, rv.Index(0)); err != nil {
+		return b, del, err
+	}
+
+	for i := 1; i < n; i++ {
+		b = append(b, del...)
+		if b, del, err = appendArrayElement(b, rv.Index(i)); err != nil {
+			return b, del, err
+		}
+	}
+
+	return append(b, '}'), del, nil
+}
+
+// appendArrayElement appends rv to the buffer, returning the extended buffer
+// and the delimiter to use before the next element.
+//
+// When rv's Kind is neither reflect.Array nor reflect.Slice, it is converted
+// using driver.DefaultParameterConverter and the resulting []byte or string
+// is double-quoted.
+//
+// See http://www.postgresql.org/docs/current/static/arrays.html#ARRAYS-IO
+func appendArrayElement(b []byte, rv reflect.Value) ([]byte, string, error) {
+	if k := rv.Kind(); k == reflect.Array || k == reflect.Slice {
+		if t := rv.Type(); t != typeByteSlice && !t.Implements(typeDriverValuer) {
+			if n := rv.Len(); n > 0 {
+				return appendArray(b, rv, n)
+			}
+
+			return b, "", nil
+		}
+	}
+
+	var del = ","
+	var err error
+	var iv interface{} = rv.Interface()
+
+	if ad, ok := iv.(ArrayDelimiter); ok {
+		del = ad.ArrayDelimiter()
+	}
+
+	if iv, err = driver.DefaultParameterConverter.ConvertValue(iv); err != nil {
+		return b, del, err
+	}
+
+	switch v := iv.(type) {
+	case nil:
+		return append(b, "NULL"...), del, nil
+	case []byte:
+		return appendArrayQuotedBytes(b, v), del, nil
+	case string:
+		return appendArrayQuotedBytes(b, []byte(v)), del, nil
+	}
+
+	b, err = appendValue(b, iv)
+	return b, del, err
+}
+
+func appendArrayQuotedBytes(b, v []byte) []byte {
+	b = append(b, '"')
+	for {
+		i := bytes.IndexAny(v, `"\`)
+		if i < 0 {
+			b = append(b, v...)
+			break
+		}
+		if i > 0 {
+			b = append(b, v[:i]...)
+		}
+		b = append(b, '\\', v[i])
+		v = v[i+1:]
+	}
+	return append(b, '"')
+}
+
+func appendValue(b []byte, v driver.Value) ([]byte, error) {
+	return append(b, encode(nil, v, 0)...), nil
+}
+
+// parseArray extracts the dimensions and elements of an array represented in
+// text format. Only representations emitted by the backend are supported.
+// Notably, whitespace around brackets and delimiters is significant, and NULL
+// is case-sensitive.
+//
+// See http://www.postgresql.org/docs/current/static/arrays.html#ARRAYS-IO
+func parseArray(src, del []byte) (dims []int, elems [][]byte, err error) {
+	var depth, i int
+
+	if len(src) < 1 || src[0] != '{' {
+		return nil, nil, fmt.Errorf("pq: unable to parse array; expected %q at offset %d", '{', 0)
+	}
+
+Open:
+	for i < len(src) {
+		switch src[i] {
+		case '{':
+			depth++
+			i++
+		case '}':
+			elems = make([][]byte, 0)
+			goto Close
+		default:
+			break Open
+		}
+	}
+	dims = make([]int, i)
+
+Element:
+	for i < len(src) {
+		switch src[i] {
+		case '{':
+			if depth == len(dims) {
+				break Element
+			}
+			depth++
+			dims[depth-1] = 0
+			i++
+		case '"':
+			var elem = []byte{}
+			var escape bool
+			for i++; i < len(src); i++ {
+				if escape {
+					elem = append(elem, src[i])
+					escape = false
+				} else {
+					switch src[i] {
+					default:
+						elem = append(elem, src[i])
+					case '\\':
+						escape = true
+					case '"':
+						elems = append(elems, elem)
+						i++
+						break Element
+					}
+				}
+			}
+		default:
+			for start := i; i < len(src); i++ {
+				if bytes.HasPrefix(src[i:], del) || src[i] == '}' {
+					elem := src[start:i]
+					if len(elem) == 0 {
+						return nil, nil, fmt.Errorf("pq: unable to parse array; unexpected %q at offset %d", src[i], i)
+					}
+					if bytes.Equal(elem, []byte("NULL")) {
+						elem = nil
+					}
+					elems = append(elems, elem)
+					break Element
+				}
+			}
+		}
+	}
+
+	for i < len(src) {
+		if bytes.HasPrefix(src[i:], del) && depth > 0 {
+			dims[depth-1]++
+			i += len(del)
+			goto Element
+		} else if src[i] == '}' && depth > 0 {
+			dims[depth-1]++
+			depth--
+			i++
+		} else {
+			return nil, nil, fmt.Errorf("pq: unable to parse array; unexpected %q at offset %d", src[i], i)
+		}
+	}
+
+Close:
+	for i < len(src) {
+		if src[i] == '}' && depth > 0 {
+			depth--
+			i++
+		} else {
+			return nil, nil, fmt.Errorf("pq: unable to parse array; unexpected %q at offset %d", src[i], i)
+		}
+	}
+	if depth > 0 {
+		err = fmt.Errorf("pq: unable to parse array; expected %q at offset %d", '}', i)
+	}
+	if err == nil {
+		for _, d := range dims {
+			if (len(elems) % d) != 0 {
+				err = fmt.Errorf("pq: multidimensional arrays must have elements with matching dimensions")
+			}
+		}
+	}
+	return
+}
+
+func scanLinearArray(src, del []byte, typ string) (elems [][]byte, err error) {
+	dims, elems, err := parseArray(src, del)
+	if err != nil {
+		return nil, err
+	}
+	if len(dims) > 1 {
+		return nil, fmt.Errorf("pq: cannot convert ARRAY%s to %s", strings.Replace(fmt.Sprint(dims), " ", "][", -1), typ)
+	}
+	return elems, err
+}

vendor/github.com/lib/pq/buf.go

@@ -0,0 +1,91 @@
+package pq
+
+import (
+	"bytes"
+	"encoding/binary"
+
+	"github.com/lib/pq/oid"
+)
+
+type readBuf []byte
+
+func (b *readBuf) int32() (n int) {
+	n = int(int32(binary.BigEndian.Uint32(*b)))
+	*b = (*b)[4:]
+	return
+}
+
+func (b *readBuf) oid() (n oid.Oid) {
+	n = oid.Oid(binary.BigEndian.Uint32(*b))
+	*b = (*b)[4:]
+	return
+}
+
+// N.B: this is actually an unsigned 16-bit integer, unlike int32
+func (b *readBuf) int16() (n int) {
+	n = int(binary.BigEndian.Uint16(*b))
+	*b = (*b)[2:]
+	return
+}
+
+func (b *readBuf) string() string {
+	i := bytes.IndexByte(*b, 0)
+	if i < 0 {
+		errorf("invalid message format; expected string terminator")
+	}
+	s := (*b)[:i]
+	*b = (*b)[i+1:]
+	return string(s)
+}
+
+func (b *readBuf) next(n int) (v []byte) {
+	v = (*b)[:n]
+	*b = (*b)[n:]
+	return
+}
+
+func (b *readBuf) byte() byte {
+	return b.next(1)[0]
+}
+
+type writeBuf struct {
+	buf []byte
+	pos int
+}
+
+func (b *writeBuf) int32(n int) {
+	x := make([]byte, 4)
+	binary.BigEndian.PutUint32(x, uint32(n))
+	b.buf = append(b.buf, x...)
+}
+
+func (b *writeBuf) int16(n int) {
+	x := make([]byte, 2)
+	binary.BigEndian.PutUint16(x, uint16(n))
+	b.buf = append(b.buf, x...)
+}
+
+func (b *writeBuf) string(s string) {
+	b.buf = append(append(b.buf, s...), '\000')
+}
+
+func (b *writeBuf) byte(c byte) {
+	b.buf = append(b.buf, c)
+}
+
+func (b *writeBuf) bytes(v []byte) {
+	b.buf = append(b.buf, v...)
+}
+
+func (b *writeBuf) wrap() []byte {
+	p := b.buf[b.pos:]
+	binary.BigEndian.PutUint32(p, uint32(len(p)))
+	return b.buf
+}
+
+func (b *writeBuf) next(c byte) {
+	p := b.buf[b.pos:]
+	binary.BigEndian.PutUint32(p, uint32(len(p)))
+	b.pos = len(b.buf) + 1
+	b.buf = append(b.buf, c, 0, 0, 0, 0)
+}

vendor/github.com/lib/pq/conn_go115.go

@@ -0,0 +1,8 @@
+//go:build go1.15
+// +build go1.15
+
+package pq
+
+import "database/sql/driver"
+
+var _ driver.Validator = &conn{}

vendor/github.com/lib/pq/conn_go18.go

@@ -0,0 +1,247 @@
+package pq
+
+import (
+	"context"
+	"database/sql"
+	"database/sql/driver"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"time"
+)
+
+const (
+	watchCancelDialContextTimeout = time.Second * 10
+)
+
+// Implement the "QueryerContext" interface
+func (cn *conn) QueryContext(ctx context.Context, query string, args []driver.NamedValue) (driver.Rows, error) {
+	list := make([]driver.Value, len(args))
+	for i, nv := range args {
+		list[i] = nv.Value
+	}
+	finish := cn.watchCancel(ctx)
+	r, err := cn.query(query, list)
+	if err != nil {
+		if finish != nil {
+			finish()
+		}
+		return nil, err
+	}
+	r.finish = finish
+	return r, nil
+}
+
+// Implement the "ExecerContext" interface
+func (cn *conn) ExecContext(ctx context.Context, query string, args []driver.NamedValue) (driver.Result, error) {
+	list := make([]driver.Value, len(args))
+	for i, nv := range args {
+		list[i] = nv.Value
+	}
+
+	if finish := cn.watchCancel(ctx); finish != nil {
+		defer finish()
+	}
+
+	return cn.Exec(query, list)
+}
+
+// Implement the "ConnPrepareContext" interface
+func (cn *conn) PrepareContext(ctx context.Context, query string) (driver.Stmt, error) {
+	if finish := cn.watchCancel(ctx); finish != nil {
+		defer finish()
+	}
+	return cn.Prepare(query)
+}
+
+// Implement the "ConnBeginTx" interface
+func (cn *conn) BeginTx(ctx context.Context, opts driver.TxOptions) (driver.Tx, error) {
+	var mode string
+
+	switch sql.IsolationLevel(opts.Isolation) {
+	case sql.LevelDefault:
+		// Don't touch mode: use the server's default
+	case sql.LevelReadUncommitted:
+		mode = " ISOLATION LEVEL READ UNCOMMITTED"
+	case sql.LevelReadCommitted:
+		mode = " ISOLATION LEVEL READ COMMITTED"
+	case sql.LevelRepeatableRead:
+		mode = " ISOLATION LEVEL REPEATABLE READ"
+	case sql.LevelSerializable:
+		mode = " ISOLATION LEVEL SERIALIZABLE"
+	default:
+		return nil, fmt.Errorf("pq: isolation level not supported: %d", opts.Isolation)
+	}
+
+	if opts.ReadOnly {
+		mode += " READ ONLY"
+	} else {
+		mode += " READ WRITE"
+	}
+
+	tx, err := cn.begin(mode)
+	if err != nil {
+		return nil, err
+	}
+	cn.txnFinish = cn.watchCancel(ctx)
+	return tx, nil
+}
+
+func (cn *conn) Ping(ctx context.Context) error {
+	if finish := cn.watchCancel(ctx); finish != nil {
+		defer finish()
+	}
+	rows, err := cn.simpleQuery(";")
+	if err != nil {
+		return driver.ErrBadConn // https://golang.org/pkg/database/sql/driver/#Pinger
+	}
+	rows.Close()
+	return nil
+}
+
+func (cn *conn) watchCancel(ctx context.Context) func() {
+	if done := ctx.Done(); done != nil {
+		finished := make(chan struct{}, 1)
+		go func() {
+			select {
+			case <-done:
+				select {
+				case finished <- struct{}{}:
+				default:
+					// We raced with the finish func, let the next query handle this with the
+					// context.
+					return
+				}
+
+				// Set the connection state to bad so it does not get reused.
+				cn.err.set(ctx.Err())
+
+				// At this point the function level context is canceled,
+				// so it must not be used for the additional network
+				// request to cancel the query.
+				// Create a new context to pass into the dial.
+				ctxCancel, cancel := context.WithTimeout(context.Background(), watchCancelDialContextTimeout)
+				defer cancel()
+
+				_ = cn.cancel(ctxCancel)
+			case <-finished:
+			}
+		}()
+		return func() {
+			select {
+			case <-finished:
+				cn.err.set(ctx.Err())
+				cn.Close()
+			case finished <- struct{}{}:
+			}
+		}
+	}
+	return nil
+}
+
+func (cn *conn) cancel(ctx context.Context) error {
+	// Create a new values map (copy). This makes sure the connection created
+	// in this method cannot write to the same underlying data, which could
+	// cause a concurrent map write panic. This is necessary because cancel
+	// is called from a goroutine in watchCancel.
+	o := make(values)
+	for k, v := range cn.opts {
+		o[k] = v
+	}
+
+	c, err := dial(ctx, cn.dialer, o)
+	if err != nil {
+		return err
+	}
+	defer c.Close()
+
+	{
+		can := conn{
+			c: c,
+		}
+		err = can.ssl(o)
+		if err != nil {
+			return err
+		}
+
+		w := can.writeBuf(0)
+		w.int32(80877102) // cancel request code
+		w.int32(cn.processID)
+		w.int32(cn.secretKey)
+
+		if err := can.sendStartupPacket(w); err != nil {
+			return err
+		}
+	}
+
+	// Read until EOF to ensure that the server received the cancel.
+	{
+		_, err := io.Copy(ioutil.Discard, c)
+		return err
+	}
+}
+
+// Implement the "StmtQueryContext" interface
+func (st *stmt) QueryContext(ctx context.Context, args []driver.NamedValue) (driver.Rows, error) {
+	list := make([]driver.Value, len(args))
+	for i, nv := range args {
+		list[i] = nv.Value
+	}
+	finish := st.watchCancel(ctx)
+	r, err := st.query(list)
+	if err != nil {
+		if finish != nil {
+			finish()
+		}
+		return nil, err
+	}
+	r.finish = finish
+	return r, nil
+}
+
+// Implement the "StmtExecContext" interface
+func (st *stmt) ExecContext(ctx context.Context, args []driver.NamedValue) (driver.Result, error) {
+	list := make([]driver.Value, len(args))
+	for i, nv := range args {
+		list[i] = nv.Value
+	}
+
+	if finish := st.watchCancel(ctx); finish != nil {
+		defer finish()
+	}
+
+	return st.Exec(list)
+}
+
+// watchCancel is implemented on stmt in order to not mark the parent conn as bad
+func (st *stmt) watchCancel(ctx context.Context) func() {
+	if done := ctx.Done(); done != nil {
+		finished := make(chan struct{})
+		go func() {
+			select {
+			case <-done:
+				// At this point the function level context is canceled,
+				// so it must not be used for the additional network
+				// request to cancel the query.
+				// Create a new context to pass into the dial.
+				ctxCancel, cancel := context.WithTimeout(context.Background(), watchCancelDialContextTimeout)
+				defer cancel()
+
+				_ = st.cancel(ctxCancel)
+				finished <- struct{}{}
+			case <-finished:
+			}
+		}()
+		return func() {
+			select {
+			case <-finished:
+			case finished <- struct{}{}:
+			}
+		}
+	}
+	return nil
+}
+
+func (st *stmt) cancel(ctx context.Context) error {
+	return st.cn.cancel(ctx)
+}

vendor/github.com/lib/pq/connector.go

@@ -0,0 +1,120 @@
+package pq
+
+import (
+	"context"
+	"database/sql/driver"
+	"errors"
+	"fmt"
+	"os"
+	"strings"
+)
+
+// Connector represents a fixed configuration for the pq driver with a given
+// name. Connector satisfies the database/sql/driver Connector interface and
+// can be used to create any number of DB Conn's via the database/sql OpenDB
+// function.
+//
+// See https://golang.org/pkg/database/sql/driver/#Connector.
+// See https://golang.org/pkg/database/sql/#OpenDB.
+type Connector struct {
+	opts   values
+	dialer Dialer
+}
+
+// Connect returns a connection to the database using the fixed configuration
+// of this Connector. Context is not used.
+func (c *Connector) Connect(ctx context.Context) (driver.Conn, error) {
+	return c.open(ctx)
+}
+
+// Dialer allows change the dialer used to open connections.
+func (c *Connector) Dialer(dialer Dialer) {
+	c.dialer = dialer
+}
+
+// Driver returns the underlying driver of this Connector.
+func (c *Connector) Driver() driver.Driver {
+	return &Driver{}
+}
+
+// NewConnector returns a connector for the pq driver in a fixed configuration
+// with the given dsn. The returned connector can be used to create any number
+// of equivalent Conn's. The returned connector is intended to be used with
+// database/sql.OpenDB.
+//
+// See https://golang.org/pkg/database/sql/driver/#Connector.
+// See https://golang.org/pkg/database/sql/#OpenDB.
+func NewConnector(dsn string) (*Connector, error) {
+	var err error
+	o := make(values)
+
+	// A number of defaults are applied here, in this order:
+	//
+	// * Very low precedence defaults applied in every situation
+	// * Environment variables
+	// * Explicitly passed connection information
+	o["host"] = "localhost"
+	o["port"] = "5432"
+	// N.B.: Extra float digits should be set to 3, but that breaks
+	// Postgres 8.4 and older, where the max is 2.
+	o["extra_float_digits"] = "2"
+	for k, v := range parseEnviron(os.Environ()) {
+		o[k] = v
+	}
+
+	if strings.HasPrefix(dsn, "postgres://") || strings.HasPrefix(dsn, "postgresql://") {
+		dsn, err = ParseURL(dsn)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	if err := parseOpts(dsn, o); err != nil {
+		return nil, err
+	}
+
+	// Use the "fallback" application name if necessary
+	if fallback, ok := o["fallback_application_name"]; ok {
+		if _, ok := o["application_name"]; !ok {
+			o["application_name"] = fallback
+		}
+	}
+
+	// We can't work with any client_encoding other than UTF-8 currently.
+	// However, we have historically allowed the user to set it to UTF-8
+	// explicitly, and there's no reason to break such programs, so allow that.
+	// Note that the "options" setting could also set client_encoding, but
+	// parsing its value is not worth it.  Instead, we always explicitly send
+	// client_encoding as a separate run-time parameter, which should override
+	// anything set in options.
+	if enc, ok := o["client_encoding"]; ok && !isUTF8(enc) {
+		return nil, errors.New("client_encoding must be absent or 'UTF8'")
+	}
+	o["client_encoding"] = "UTF8"
+	// DateStyle needs a similar treatment.
+	if datestyle, ok := o["datestyle"]; ok {
+		if datestyle != "ISO, MDY" {
+			return nil, fmt.Errorf("setting datestyle must be absent or %v; got %v", "ISO, MDY", datestyle)
+		}
+	} else {
+		o["datestyle"] = "ISO, MDY"
+	}
+
+	// If a user is not provided by any other means, the last
+	// resort is to use the current operating system provided user
+	// name.
+	if _, ok := o["user"]; !ok {
+		u, err := userCurrent()
+		if err != nil {
+			return nil, err
+		}
+		o["user"] = u
+	}
+
+	// SSL is not necessary or supported over UNIX domain sockets
+	if network, _ := network(o); network == "unix" {
+		o["sslmode"] = "disable"
+	}
+
+	return &Connector{opts: o, dialer: defaultDialer{}}, nil
+}

vendor/github.com/lib/pq/copy.go

@@ -0,0 +1,348 @@
+package pq
+
+import (
+	"bytes"
+	"context"
+	"database/sql/driver"
+	"encoding/binary"
+	"errors"
+	"fmt"
+	"sync"
+)
+
+var (
+	errCopyInClosed               = errors.New("pq: copyin statement has already been closed")
+	errBinaryCopyNotSupported     = errors.New("pq: only text format supported for COPY")
+	errCopyToNotSupported         = errors.New("pq: COPY TO is not supported")
+	errCopyNotSupportedOutsideTxn = errors.New("pq: COPY is only allowed inside a transaction")
+	errCopyInProgress             = errors.New("pq: COPY in progress")
+)
+
+// CopyIn creates a COPY FROM statement which can be prepared with
+// Tx.Prepare().  The target table should be visible in search_path.
+func CopyIn(table string, columns ...string) string {
+	buffer := bytes.NewBufferString("COPY ")
+	BufferQuoteIdentifier(table, buffer)
+	buffer.WriteString(" (")
+	makeStmt(buffer, columns...)
+	return buffer.String()
+}
+
+// MakeStmt makes the stmt string for CopyIn and CopyInSchema.
+func makeStmt(buffer *bytes.Buffer, columns ...string) {
+	//s := bytes.NewBufferString()
+	for i, col := range columns {
+		if i != 0 {
+			buffer.WriteString(", ")
+		}
+		BufferQuoteIdentifier(col, buffer)
+	}
+	buffer.WriteString(") FROM STDIN")
+}
+
+// CopyInSchema creates a COPY FROM statement which can be prepared with
+// Tx.Prepare().
+func CopyInSchema(schema, table string, columns ...string) string {
+	buffer := bytes.NewBufferString("COPY ")
+	BufferQuoteIdentifier(schema, buffer)
+	buffer.WriteRune('.')
+	BufferQuoteIdentifier(table, buffer)
+	buffer.WriteString(" (")
+	makeStmt(buffer, columns...)
+	return buffer.String()
+}
+
+type copyin struct {
+	cn      *conn
+	buffer  []byte
+	rowData chan []byte
+	done    chan bool
+
+	closed bool
+
+	mu struct {
+		sync.Mutex
+		err error
+		driver.Result
+	}
+}
+
+const ciBufferSize = 64 * 1024
+
+// flush buffer before the buffer is filled up and needs reallocation
+const ciBufferFlushSize = 63 * 1024
+
+func (cn *conn) prepareCopyIn(q string) (_ driver.Stmt, err error) {
+	if !cn.isInTransaction() {
+		return nil, errCopyNotSupportedOutsideTxn
+	}
+
+	ci := &copyin{
+		cn:      cn,
+		buffer:  make([]byte, 0, ciBufferSize),
+		rowData: make(chan []byte),
+		done:    make(chan bool, 1),
+	}
+	// add CopyData identifier + 4 bytes for message length
+	ci.buffer = append(ci.buffer, 'd', 0, 0, 0, 0)
+
+	b := cn.writeBuf('Q')
+	b.string(q)
+	cn.send(b)
+
+awaitCopyInResponse:
+	for {
+		t, r := cn.recv1()
+		switch t {
+		case 'G':
+			if r.byte() != 0 {
+				err = errBinaryCopyNotSupported
+				break awaitCopyInResponse
+			}
+			go ci.resploop()
+			return ci, nil
+		case 'H':
+			err = errCopyToNotSupported
+			break awaitCopyInResponse
+		case 'E':
+			err = parseError(r)
+		case 'Z':
+			if err == nil {
+				ci.setBad(driver.ErrBadConn)
+				errorf("unexpected ReadyForQuery in response to COPY")
+			}
+			cn.processReadyForQuery(r)
+			return nil, err
+		default:
+			ci.setBad(driver.ErrBadConn)
+			errorf("unknown response for copy query: %q", t)
+		}
+	}
+
+	// something went wrong, abort COPY before we return
+	b = cn.writeBuf('f')
+	b.string(err.Error())
+	cn.send(b)
+
+	for {
+		t, r := cn.recv1()
+		switch t {
+		case 'c', 'C', 'E':
+		case 'Z':
+			// correctly aborted, we're done
+			cn.processReadyForQuery(r)
+			return nil, err
+		default:
+			ci.setBad(driver.ErrBadConn)
+			errorf("unknown response for CopyFail: %q", t)
+		}
+	}
+}
+
+func (ci *copyin) flush(buf []byte) {
+	// set message length (without message identifier)
+	binary.BigEndian.PutUint32(buf[1:], uint32(len(buf)-1))
+
+	_, err := ci.cn.c.Write(buf)
+	if err != nil {
+		panic(err)
+	}
+}
+
+func (ci *copyin) resploop() {
+	for {
+		var r readBuf
+		t, err := ci.cn.recvMessage(&r)
+		if err != nil {
+			ci.setBad(driver.ErrBadConn)
+			ci.setError(err)
+			ci.done <- true
+			return
+		}
+		switch t {
+		case 'C':
+			// complete
+			res, _ := ci.cn.parseComplete(r.string())
+			ci.setResult(res)
+		case 'N':
+			if n := ci.cn.noticeHandler; n != nil {
+				n(parseError(&r))
+			}
+		case 'Z':
+			ci.cn.processReadyForQuery(&r)
+			ci.done <- true
+			return
+		case 'E':
+			err := parseError(&r)
+			ci.setError(err)
+		default:
+			ci.setBad(driver.ErrBadConn)
+			ci.setError(fmt.Errorf("unknown response during CopyIn: %q", t))
+			ci.done <- true
+			return
+		}
+	}
+}
+
+func (ci *copyin) setBad(err error) {
+	ci.cn.err.set(err)
+}
+
+func (ci *copyin) getBad() error {
+	return ci.cn.err.get()
+}
+
+func (ci *copyin) err() error {
+	ci.mu.Lock()
+	err := ci.mu.err
+	ci.mu.Unlock()
+	return err
+}
+
+// setError() sets ci.err if one has not been set already.  Caller must not be
+// holding ci.Mutex.
+func (ci *copyin) setError(err error) {
+	ci.mu.Lock()
+	if ci.mu.err == nil {
+		ci.mu.err = err
+	}
+	ci.mu.Unlock()
+}
+
+func (ci *copyin) setResult(result driver.Result) {
+	ci.mu.Lock()
+	ci.mu.Result = result
+	ci.mu.Unlock()
+}
+
+func (ci *copyin) getResult() driver.Result {
+	ci.mu.Lock()
+	result := ci.mu.Result
+	ci.mu.Unlock()
+	if result == nil {
+		return driver.RowsAffected(0)
+	}
+	return result
+}
+
+func (ci *copyin) NumInput() int {
+	return -1
+}
+
+func (ci *copyin) Query(v []driver.Value) (r driver.Rows, err error) {
+	return nil, ErrNotSupported
+}
+
+// Exec inserts values into the COPY stream. The insert is asynchronous
+// and Exec can return errors from previous Exec calls to the same
+// COPY stmt.
+//
+// You need to call Exec(nil) to sync the COPY stream and to get any
+// errors from pending data, since Stmt.Close() doesn't return errors
+// to the user.
+func (ci *copyin) Exec(v []driver.Value) (r driver.Result, err error) {
+	if ci.closed {
+		return nil, errCopyInClosed
+	}
+
+	if err := ci.getBad(); err != nil {
+		return nil, err
+	}
+	defer ci.cn.errRecover(&err)
+
+	if err := ci.err(); err != nil {
+		return nil, err
+	}
+
+	if len(v) == 0 {
+		if err := ci.Close(); err != nil {
+			return driver.RowsAffected(0), err
+		}
+
+		return ci.getResult(), nil
+	}
+
+	numValues := len(v)
+	for i, value := range v {
+		ci.buffer = appendEncodedText(&ci.cn.parameterStatus, ci.buffer, value)
+		if i < numValues-1 {
+			ci.buffer = append(ci.buffer, '\t')
+		}
+	}
+
+	ci.buffer = append(ci.buffer, '\n')
+
+	if len(ci.buffer) > ciBufferFlushSize {
+		ci.flush(ci.buffer)
+		// reset buffer, keep bytes for message identifier and length
+		ci.buffer = ci.buffer[:5]
+	}
+
+	return driver.RowsAffected(0), nil
+}
+
+// CopyData inserts a raw string into the COPY stream. The insert is
+// asynchronous and CopyData can return errors from previous CopyData calls to
+// the same COPY stmt.
+//
+// You need to call Exec(nil) to sync the COPY stream and to get any
+// errors from pending data, since Stmt.Close() doesn't return errors
+// to the user.
+func (ci *copyin) CopyData(ctx context.Context, line string) (r driver.Result, err error) {
+	if ci.closed {
+		return nil, errCopyInClosed
+	}
+
+	if finish := ci.cn.watchCancel(ctx); finish != nil {
+		defer finish()
+	}
+
+	if err := ci.getBad(); err != nil {
+		return nil, err
+	}
+	defer ci.cn.errRecover(&err)
+
+	if err := ci.err(); err != nil {
+		return nil, err
+	}
+
+	ci.buffer = append(ci.buffer, []byte(line)...)
+	ci.buffer = append(ci.buffer, '\n')
+
+	if len(ci.buffer) > ciBufferFlushSize {
+		ci.flush(ci.buffer)
+		// reset buffer, keep bytes for message identifier and length
+		ci.buffer = ci.buffer[:5]
+	}
+
+	return driver.RowsAffected(0), nil
+}
+
+func (ci *copyin) Close() (err error) {
+	if ci.closed { // Don't do anything, we're already closed
+		return nil
+	}
+	ci.closed = true
+
+	if err := ci.getBad(); err != nil {
+		return err
+	}
+	defer ci.cn.errRecover(&err)
+
+	if len(ci.buffer) > 0 {
+		ci.flush(ci.buffer)
+	}
+	// Avoid touching the scratch buffer as resploop could be using it.
+	err = ci.cn.sendSimpleMessage('c')
+	if err != nil {
+		return err
+	}
+
+	<-ci.done
+	ci.cn.inCopy = false
+
+	if err := ci.err(); err != nil {
+		return err
+	}
+	return nil
+}

vendor/github.com/lib/pq/doc.go

@@ -0,0 +1,268 @@
+/*
+Package pq is a pure Go Postgres driver for the database/sql package.
+
+In most cases clients will use the database/sql package instead of
+using this package directly. For example:
+
+	import (
+		"database/sql"
+
+		_ "github.com/lib/pq"
+	)
+
+	func main() {
+		connStr := "user=pqgotest dbname=pqgotest sslmode=verify-full"
+		db, err := sql.Open("postgres", connStr)
+		if err != nil {
+			log.Fatal(err)
+		}
+
+		age := 21
+		rows, err := db.Query("SELECT name FROM users WHERE age = $1", age)
+		…
+	}
+
+You can also connect to a database using a URL. For example:
+
+	connStr := "postgres://pqgotest:password@localhost/pqgotest?sslmode=verify-full"
+	db, err := sql.Open("postgres", connStr)
+
+
+Connection String Parameters
+
+
+Similarly to libpq, when establishing a connection using pq you are expected to
+supply a connection string containing zero or more parameters.
+A subset of the connection parameters supported by libpq are also supported by pq.
+Additionally, pq also lets you specify run-time parameters (such as search_path or work_mem)
+directly in the connection string.  This is different from libpq, which does not allow
+run-time parameters in the connection string, instead requiring you to supply
+them in the options parameter.
+
+For compatibility with libpq, the following special connection parameters are
+supported:
+
+	* dbname - The name of the database to connect to
+	* user - The user to sign in as
+	* password - The user's password
+	* host - The host to connect to. Values that start with / are for unix
+	  domain sockets. (default is localhost)
+	* port - The port to bind to. (default is 5432)
+	* sslmode - Whether or not to use SSL (default is require, this is not
+	  the default for libpq)
+	* fallback_application_name - An application_name to fall back to if one isn't provided.
+	* connect_timeout - Maximum wait for connection, in seconds. Zero or
+	  not specified means wait indefinitely.
+	* sslcert - Cert file location. The file must contain PEM encoded data.
+	* sslkey - Key file location. The file must contain PEM encoded data.
+	* sslrootcert - The location of the root certificate file. The file
+	  must contain PEM encoded data.
+
+Valid values for sslmode are:
+
+	* disable - No SSL
+	* require - Always SSL (skip verification)
+	* verify-ca - Always SSL (verify that the certificate presented by the
+	  server was signed by a trusted CA)
+	* verify-full - Always SSL (verify that the certification presented by
+	  the server was signed by a trusted CA and the server host name
+	  matches the one in the certificate)
+
+See http://www.postgresql.org/docs/current/static/libpq-connect.html#LIBPQ-CONNSTRING
+for more information about connection string parameters.
+
+Use single quotes for values that contain whitespace:
+
+    "user=pqgotest password='with spaces'"
+
+A backslash will escape the next character in values:
+
+    "user=space\ man password='it\'s valid'"
+
+Note that the connection parameter client_encoding (which sets the
+text encoding for the connection) may be set but must be "UTF8",
+matching with the same rules as Postgres. It is an error to provide
+any other value.
+
+In addition to the parameters listed above, any run-time parameter that can be
+set at backend start time can be set in the connection string.  For more
+information, see
+http://www.postgresql.org/docs/current/static/runtime-config.html.
+
+Most environment variables as specified at http://www.postgresql.org/docs/current/static/libpq-envars.html
+supported by libpq are also supported by pq.  If any of the environment
+variables not supported by pq are set, pq will panic during connection
+establishment.  Environment variables have a lower precedence than explicitly
+provided connection parameters.
+
+The pgpass mechanism as described in http://www.postgresql.org/docs/current/static/libpq-pgpass.html
+is supported, but on Windows PGPASSFILE must be specified explicitly.
+
+
+Queries
+
+
+database/sql does not dictate any specific format for parameter
+markers in query strings, and pq uses the Postgres-native ordinal markers,
+as shown above. The same marker can be reused for the same parameter:
+
+	rows, err := db.Query(`SELECT name FROM users WHERE favorite_fruit = $1
+		OR age BETWEEN $2 AND $2 + 3`, "orange", 64)
+
+pq does not support the LastInsertId() method of the Result type in database/sql.
+To return the identifier of an INSERT (or UPDATE or DELETE), use the Postgres
+RETURNING clause with a standard Query or QueryRow call:
+
+	var userid int
+	err := db.QueryRow(`INSERT INTO users(name, favorite_fruit, age)
+		VALUES('beatrice', 'starfruit', 93) RETURNING id`).Scan(&userid)
+
+For more details on RETURNING, see the Postgres documentation:
+
+	http://www.postgresql.org/docs/current/static/sql-insert.html
+	http://www.postgresql.org/docs/current/static/sql-update.html
+	http://www.postgresql.org/docs/current/static/sql-delete.html
+
+For additional instructions on querying see the documentation for the database/sql package.
+
+
+Data Types
+
+
+Parameters pass through driver.DefaultParameterConverter before they are handled
+by this package. When the binary_parameters connection option is enabled,
+[]byte values are sent directly to the backend as data in binary format.
+
+This package returns the following types for values from the PostgreSQL backend:
+
+	- integer types smallint, integer, and bigint are returned as int64
+	- floating-point types real and double precision are returned as float64
+	- character types char, varchar, and text are returned as string
+	- temporal types date, time, timetz, timestamp, and timestamptz are
+	  returned as time.Time
+	- the boolean type is returned as bool
+	- the bytea type is returned as []byte
+
+All other types are returned directly from the backend as []byte values in text format.
+
+
+Errors
+
+
+pq may return errors of type *pq.Error which can be interrogated for error details:
+
+        if err, ok := err.(*pq.Error); ok {
+            fmt.Println("pq error:", err.Code.Name())
+        }
+
+See the pq.Error type for details.
+
+
+Bulk imports
+
+You can perform bulk imports by preparing a statement returned by pq.CopyIn (or
+pq.CopyInSchema) in an explicit transaction (sql.Tx). The returned statement
+handle can then be repeatedly "executed" to copy data into the target table.
+After all data has been processed you should call Exec() once with no arguments
+to flush all buffered data. Any call to Exec() might return an error which
+should be handled appropriately, but because of the internal buffering an error
+returned by Exec() might not be related to the data passed in the call that
+failed.
+
+CopyIn uses COPY FROM internally. It is not possible to COPY outside of an
+explicit transaction in pq.
+
+Usage example:
+
+	txn, err := db.Begin()
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	stmt, err := txn.Prepare(pq.CopyIn("users", "name", "age"))
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	for _, user := range users {
+		_, err = stmt.Exec(user.Name, int64(user.Age))
+		if err != nil {
+			log.Fatal(err)
+		}
+	}
+
+	_, err = stmt.Exec()
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	err = stmt.Close()
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	err = txn.Commit()
+	if err != nil {
+		log.Fatal(err)
+	}
+
+
+Notifications
+
+
+PostgreSQL supports a simple publish/subscribe model over database
+connections.  See http://www.postgresql.org/docs/current/static/sql-notify.html
+for more information about the general mechanism.
+
+To start listening for notifications, you first have to open a new connection
+to the database by calling NewListener.  This connection can not be used for
+anything other than LISTEN / NOTIFY.  Calling Listen will open a "notification
+channel"; once a notification channel is open, a notification generated on that
+channel will effect a send on the Listener.Notify channel.  A notification
+channel will remain open until Unlisten is called, though connection loss might
+result in some notifications being lost.  To solve this problem, Listener sends
+a nil pointer over the Notify channel any time the connection is re-established
+following a connection loss.  The application can get information about the
+state of the underlying connection by setting an event callback in the call to
+NewListener.
+
+A single Listener can safely be used from concurrent goroutines, which means
+that there is often no need to create more than one Listener in your
+application.  However, a Listener is always connected to a single database, so
+you will need to create a new Listener instance for every database you want to
+receive notifications in.
+
+The channel name in both Listen and Unlisten is case sensitive, and can contain
+any characters legal in an identifier (see
+http://www.postgresql.org/docs/current/static/sql-syntax-lexical.html#SQL-SYNTAX-IDENTIFIERS
+for more information).  Note that the channel name will be truncated to 63
+bytes by the PostgreSQL server.
+
+You can find a complete, working example of Listener usage at
+https://godoc.org/github.com/lib/pq/example/listen.
+
+
+Kerberos Support
+
+
+If you need support for Kerberos authentication, add the following to your main
+package:
+
+	import "github.com/lib/pq/auth/kerberos"
+
+	func init() {
+		pq.RegisterGSSProvider(func() (pq.Gss, error) { return kerberos.NewGSS() })
+	}
+
+This package is in a separate module so that users who don't need Kerberos
+don't have to download unnecessary dependencies.
+
+When imported, additional connection string parameters are supported:
+
+	* krbsrvname - GSS (Kerberos) service name when constructing the
+	  SPN (default is `postgres`). This will be combined with the host
+	  to form the full SPN: `krbsrvname/host`.
+	* krbspn - GSS (Kerberos) SPN. This takes priority over
+	  `krbsrvname` if present.
+*/
+package pq

vendor/github.com/lib/pq/encode.go

@@ -0,0 +1,632 @@
+package pq
+
+import (
+	"bytes"
+	"database/sql/driver"
+	"encoding/binary"
+	"encoding/hex"
+	"errors"
+	"fmt"
+	"math"
+	"regexp"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/lib/pq/oid"
+)
+
+var time2400Regex = regexp.MustCompile(`^(24:00(?::00(?:\.0+)?)?)(?:[Z+-].*)?$`)
+
+func binaryEncode(parameterStatus *parameterStatus, x interface{}) []byte {
+	switch v := x.(type) {
+	case []byte:
+		return v
+	default:
+		return encode(parameterStatus, x, oid.T_unknown)
+	}
+}
+
+func encode(parameterStatus *parameterStatus, x interface{}, pgtypOid oid.Oid) []byte {
+	switch v := x.(type) {
+	case int64:
+		return strconv.AppendInt(nil, v, 10)
+	case float64:
+		return strconv.AppendFloat(nil, v, 'f', -1, 64)
+	case []byte:
+		if pgtypOid == oid.T_bytea {
+			return encodeBytea(parameterStatus.serverVersion, v)
+		}
+
+		return v
+	case string:
+		if pgtypOid == oid.T_bytea {
+			return encodeBytea(parameterStatus.serverVersion, []byte(v))
+		}
+
+		return []byte(v)
+	case bool:
+		return strconv.AppendBool(nil, v)
+	case time.Time:
+		return formatTs(v)
+
+	default:
+		errorf("encode: unknown type for %T", v)
+	}
+
+	panic("not reached")
+}
+
+func decode(parameterStatus *parameterStatus, s []byte, typ oid.Oid, f format) interface{} {
+	switch f {
+	case formatBinary:
+		return binaryDecode(parameterStatus, s, typ)
+	case formatText:
+		return textDecode(parameterStatus, s, typ)
+	default:
+		panic("not reached")
+	}
+}
+
+func binaryDecode(parameterStatus *parameterStatus, s []byte, typ oid.Oid) interface{} {
+	switch typ {
+	case oid.T_bytea:
+		return s
+	case oid.T_int8:
+		return int64(binary.BigEndian.Uint64(s))
+	case oid.T_int4:
+		return int64(int32(binary.BigEndian.Uint32(s)))
+	case oid.T_int2:
+		return int64(int16(binary.BigEndian.Uint16(s)))
+	case oid.T_uuid:
+		b, err := decodeUUIDBinary(s)
+		if err != nil {
+			panic(err)
+		}
+		return b
+
+	default:
+		errorf("don't know how to decode binary parameter of type %d", uint32(typ))
+	}
+
+	panic("not reached")
+}
+
+func textDecode(parameterStatus *parameterStatus, s []byte, typ oid.Oid) interface{} {
+	switch typ {
+	case oid.T_char, oid.T_varchar, oid.T_text:
+		return string(s)
+	case oid.T_bytea:
+		b, err := parseBytea(s)
+		if err != nil {
+			errorf("%s", err)
+		}
+		return b
+	case oid.T_timestamptz:
+		return parseTs(parameterStatus.currentLocation, string(s))
+	case oid.T_timestamp, oid.T_date:
+		return parseTs(nil, string(s))
+	case oid.T_time:
+		return mustParse("15:04:05", typ, s)
+	case oid.T_timetz:
+		return mustParse("15:04:05-07", typ, s)
+	case oid.T_bool:
+		return s[0] == 't'
+	case oid.T_int8, oid.T_int4, oid.T_int2:
+		i, err := strconv.ParseInt(string(s), 10, 64)
+		if err != nil {
+			errorf("%s", err)
+		}
+		return i
+	case oid.T_float4, oid.T_float8:
+		// We always use 64 bit parsing, regardless of whether the input text is for
+		// a float4 or float8, because clients expect float64s for all float datatypes
+		// and returning a 32-bit parsed float64 produces lossy results.
+		f, err := strconv.ParseFloat(string(s), 64)
+		if err != nil {
+			errorf("%s", err)
+		}
+		return f
+	}
+
+	return s
+}
+
+// appendEncodedText encodes item in text format as required by COPY
+// and appends to buf
+func appendEncodedText(parameterStatus *parameterStatus, buf []byte, x interface{}) []byte {
+	switch v := x.(type) {
+	case int64:
+		return strconv.AppendInt(buf, v, 10)
+	case float64:
+		return strconv.AppendFloat(buf, v, 'f', -1, 64)
+	case []byte:
+		encodedBytea := encodeBytea(parameterStatus.serverVersion, v)
+		return appendEscapedText(buf, string(encodedBytea))
+	case string:
+		return appendEscapedText(buf, v)
+	case bool:
+		return strconv.AppendBool(buf, v)
+	case time.Time:
+		return append(buf, formatTs(v)...)
+	case nil:
+		return append(buf, "\\N"...)
+	default:
+		errorf("encode: unknown type for %T", v)
+	}
+
+	panic("not reached")
+}
+
+func appendEscapedText(buf []byte, text string) []byte {
+	escapeNeeded := false
+	startPos := 0
+	var c byte
+
+	// check if we need to escape
+	for i := 0; i < len(text); i++ {
+		c = text[i]
+		if c == '\\' || c == '\n' || c == '\r' || c == '\t' {
+			escapeNeeded = true
+			startPos = i
+			break
+		}
+	}
+	if !escapeNeeded {
+		return append(buf, text...)
+	}
+
+	// copy till first char to escape, iterate the rest
+	result := append(buf, text[:startPos]...)
+	for i := startPos; i < len(text); i++ {
+		c = text[i]
+		switch c {
+		case '\\':
+			result = append(result, '\\', '\\')
+		case '\n':
+			result = append(result, '\\', 'n')
+		case '\r':
+			result = append(result, '\\', 'r')
+		case '\t':
+			result = append(result, '\\', 't')
+		default:
+			result = append(result, c)
+		}
+	}
+	return result
+}
+
+func mustParse(f string, typ oid.Oid, s []byte) time.Time {
+	str := string(s)
+
+	// Check for a minute and second offset in the timezone.
+	if typ == oid.T_timestamptz || typ == oid.T_timetz {
+		for i := 3; i <= 6; i += 3 {
+			if str[len(str)-i] == ':' {
+				f += ":00"
+				continue
+			}
+			break
+		}
+	}
+
+	// Special case for 24:00 time.
+	// Unfortunately, golang does not parse 24:00 as a proper time.
+	// In this case, we want to try "round to the next day", to differentiate.
+	// As such, we find if the 24:00 time matches at the beginning; if so,
+	// we default it back to 00:00 but add a day later.
+	var is2400Time bool
+	switch typ {
+	case oid.T_timetz, oid.T_time:
+		if matches := time2400Regex.FindStringSubmatch(str); matches != nil {
+			// Concatenate timezone information at the back.
+			str = "00:00:00" + str[len(matches[1]):]
+			is2400Time = true
+		}
+	}
+	t, err := time.Parse(f, str)
+	if err != nil {
+		errorf("decode: %s", err)
+	}
+	if is2400Time {
+		t = t.Add(24 * time.Hour)
+	}
+	return t
+}
+
+var errInvalidTimestamp = errors.New("invalid timestamp")
+
+type timestampParser struct {
+	err error
+}
+
+func (p *timestampParser) expect(str string, char byte, pos int) {
+	if p.err != nil {
+		return
+	}
+	if pos+1 > len(str) {
+		p.err = errInvalidTimestamp
+		return
+	}
+	if c := str[pos]; c != char && p.err == nil {
+		p.err = fmt.Errorf("expected '%v' at position %v; got '%v'", char, pos, c)
+	}
+}
+
+func (p *timestampParser) mustAtoi(str string, begin int, end int) int {
+	if p.err != nil {
+		return 0
+	}
+	if begin < 0 || end < 0 || begin > end || end > len(str) {
+		p.err = errInvalidTimestamp
+		return 0
+	}
+	result, err := strconv.Atoi(str[begin:end])
+	if err != nil {
+		if p.err == nil {
+			p.err = fmt.Errorf("expected number; got '%v'", str)
+		}
+		return 0
+	}
+	return result
+}
+
+// The location cache caches the time zones typically used by the client.
+type locationCache struct {
+	cache map[int]*time.Location
+	lock  sync.Mutex
+}
+
+// All connections share the same list of timezones. Benchmarking shows that
+// about 5% speed could be gained by putting the cache in the connection and
+// losing the mutex, at the cost of a small amount of memory and a somewhat
+// significant increase in code complexity.
+var globalLocationCache = newLocationCache()
+
+func newLocationCache() *locationCache {
+	return &locationCache{cache: make(map[int]*time.Location)}
+}
+
+// Returns the cached timezone for the specified offset, creating and caching
+// it if necessary.
+func (c *locationCache) getLocation(offset int) *time.Location {
+	c.lock.Lock()
+	defer c.lock.Unlock()
+
+	location, ok := c.cache[offset]
+	if !ok {
+		location = time.FixedZone("", offset)
+		c.cache[offset] = location
+	}
+
+	return location
+}
+
+var infinityTsEnabled = false
+var infinityTsNegative time.Time
+var infinityTsPositive time.Time
+
+const (
+	infinityTsEnabledAlready        = "pq: infinity timestamp enabled already"
+	infinityTsNegativeMustBeSmaller = "pq: infinity timestamp: negative value must be smaller (before) than positive"
+)
+
+// EnableInfinityTs controls the handling of Postgres' "-infinity" and
+// "infinity" "timestamp"s.
+//
+// If EnableInfinityTs is not called, "-infinity" and "infinity" will return
+// []byte("-infinity") and []byte("infinity") respectively, and potentially
+// cause error "sql: Scan error on column index 0: unsupported driver -> Scan
+// pair: []uint8 -> *time.Time", when scanning into a time.Time value.
+//
+// Once EnableInfinityTs has been called, all connections created using this
+// driver will decode Postgres' "-infinity" and "infinity" for "timestamp",
+// "timestamp with time zone" and "date" types to the predefined minimum and
+// maximum times, respectively.  When encoding time.Time values, any time which
+// equals or precedes the predefined minimum time will be encoded to
+// "-infinity".  Any values at or past the maximum time will similarly be
+// encoded to "infinity".
+//
+// If EnableInfinityTs is called with negative >= positive, it will panic.
+// Calling EnableInfinityTs after a connection has been established results in
+// undefined behavior.  If EnableInfinityTs is called more than once, it will
+// panic.
+func EnableInfinityTs(negative time.Time, positive time.Time) {
+	if infinityTsEnabled {
+		panic(infinityTsEnabledAlready)
+	}
+	if !negative.Before(positive) {
+		panic(infinityTsNegativeMustBeSmaller)
+	}
+	infinityTsEnabled = true
+	infinityTsNegative = negative
+	infinityTsPositive = positive
+}
+
+/*
+ * Testing might want to toggle infinityTsEnabled
+ */
+func disableInfinityTs() {
+	infinityTsEnabled = false
+}
+
+// This is a time function specific to the Postgres default DateStyle
+// setting ("ISO, MDY"), the only one we currently support. This
+// accounts for the discrepancies between the parsing available with
+// time.Parse and the Postgres date formatting quirks.
+func parseTs(currentLocation *time.Location, str string) interface{} {
+	switch str {
+	case "-infinity":
+		if infinityTsEnabled {
+			return infinityTsNegative
+		}
+		return []byte(str)
+	case "infinity":
+		if infinityTsEnabled {
+			return infinityTsPositive
+		}
+		return []byte(str)
+	}
+	t, err := ParseTimestamp(currentLocation, str)
+	if err != nil {
+		panic(err)
+	}
+	return t
+}
+
+// ParseTimestamp parses Postgres' text format. It returns a time.Time in
+// currentLocation iff that time's offset agrees with the offset sent from the
+// Postgres server. Otherwise, ParseTimestamp returns a time.Time with the
+// fixed offset offset provided by the Postgres server.
+func ParseTimestamp(currentLocation *time.Location, str string) (time.Time, error) {
+	p := timestampParser{}
+
+	monSep := strings.IndexRune(str, '-')
+	// this is Gregorian year, not ISO Year
+	// In Gregorian system, the year 1 BC is followed by AD 1
+	year := p.mustAtoi(str, 0, monSep)
+	daySep := monSep + 3
+	month := p.mustAtoi(str, monSep+1, daySep)
+	p.expect(str, '-', daySep)
+	timeSep := daySep + 3
+	day := p.mustAtoi(str, daySep+1, timeSep)
+
+	minLen := monSep + len("01-01") + 1
+
+	isBC := strings.HasSuffix(str, " BC")
+	if isBC {
+		minLen += 3
+	}
+
+	var hour, minute, second int
+	if len(str) > minLen {
+		p.expect(str, ' ', timeSep)
+		minSep := timeSep + 3
+		p.expect(str, ':', minSep)
+		hour = p.mustAtoi(str, timeSep+1, minSep)
+		secSep := minSep + 3
+		p.expect(str, ':', secSep)
+		minute = p.mustAtoi(str, minSep+1, secSep)
+		secEnd := secSep + 3
+		second = p.mustAtoi(str, secSep+1, secEnd)
+	}
+	remainderIdx := monSep + len("01-01 00:00:00") + 1
+	// Three optional (but ordered) sections follow: the
+	// fractional seconds, the time zone offset, and the BC
+	// designation. We set them up here and adjust the other
+	// offsets if the preceding sections exist.
+
+	nanoSec := 0
+	tzOff := 0
+
+	if remainderIdx < len(str) && str[remainderIdx] == '.' {
+		fracStart := remainderIdx + 1
+		fracOff := strings.IndexAny(str[fracStart:], "-+Z ")
+		if fracOff < 0 {
+			fracOff = len(str) - fracStart
+		}
+		fracSec := p.mustAtoi(str, fracStart, fracStart+fracOff)
+		nanoSec = fracSec * (1000000000 / int(math.Pow(10, float64(fracOff))))
+
+		remainderIdx += fracOff + 1
+	}
+	if tzStart := remainderIdx; tzStart < len(str) && (str[tzStart] == '-' || str[tzStart] == '+') {
+		// time zone separator is always '-' or '+' or 'Z' (UTC is +00)
+		var tzSign int
+		switch c := str[tzStart]; c {
+		case '-':
+			tzSign = -1
+		case '+':
+			tzSign = +1
+		default:
+			return time.Time{}, fmt.Errorf("expected '-' or '+' at position %v; got %v", tzStart, c)
+		}
+		tzHours := p.mustAtoi(str, tzStart+1, tzStart+3)
+		remainderIdx += 3
+		var tzMin, tzSec int
+		if remainderIdx < len(str) && str[remainderIdx] == ':' {
+			tzMin = p.mustAtoi(str, remainderIdx+1, remainderIdx+3)
+			remainderIdx += 3
+		}
+		if remainderIdx < len(str) && str[remainderIdx] == ':' {
+			tzSec = p.mustAtoi(str, remainderIdx+1, remainderIdx+3)
+			remainderIdx += 3
+		}
+		tzOff = tzSign * ((tzHours * 60 * 60) + (tzMin * 60) + tzSec)
+	} else if tzStart < len(str) && str[tzStart] == 'Z' {
+		// time zone Z separator indicates UTC is +00
+		remainderIdx += 1
+	}
+
+	var isoYear int
+
+	if isBC {
+		isoYear = 1 - year
+		remainderIdx += 3
+	} else {
+		isoYear = year
+	}
+	if remainderIdx < len(str) {
+		return time.Time{}, fmt.Errorf("expected end of input, got %v", str[remainderIdx:])
+	}
+	t := time.Date(isoYear, time.Month(month), day,
+		hour, minute, second, nanoSec,
+		globalLocationCache.getLocation(tzOff))
+
+	if currentLocation != nil {
+		// Set the location of the returned Time based on the session's
+		// TimeZone value, but only if the local time zone database agrees with
+		// the remote database on the offset.
+		lt := t.In(currentLocation)
+		_, newOff := lt.Zone()
+		if newOff == tzOff {
+			t = lt
+		}
+	}
+
+	return t, p.err
+}
+
+// formatTs formats t into a format postgres understands.
+func formatTs(t time.Time) []byte {
+	if infinityTsEnabled {
+		// t <= -infinity : ! (t > -infinity)
+		if !t.After(infinityTsNegative) {
+			return []byte("-infinity")
+		}
+		// t >= infinity : ! (!t < infinity)
+		if !t.Before(infinityTsPositive) {
+			return []byte("infinity")
+		}
+	}
+	return FormatTimestamp(t)
+}
+
+// FormatTimestamp formats t into Postgres' text format for timestamps.
+func FormatTimestamp(t time.Time) []byte {
+	// Need to send dates before 0001 A.D. with " BC" suffix, instead of the
+	// minus sign preferred by Go.
+	// Beware, "0000" in ISO is "1 BC", "-0001" is "2 BC" and so on
+	bc := false
+	if t.Year() <= 0 {
+		// flip year sign, and add 1, e.g: "0" will be "1", and "-10" will be "11"
+		t = t.AddDate((-t.Year())*2+1, 0, 0)
+		bc = true
+	}
+	b := []byte(t.Format("2006-01-02 15:04:05.999999999Z07:00"))
+
+	_, offset := t.Zone()
+	offset %= 60
+	if offset != 0 {
+		// RFC3339Nano already printed the minus sign
+		if offset < 0 {
+			offset = -offset
+		}
+
+		b = append(b, ':')
+		if offset < 10 {
+			b = append(b, '0')
+		}
+		b = strconv.AppendInt(b, int64(offset), 10)
+	}
+
+	if bc {
+		b = append(b, " BC"...)
+	}
+	return b
+}
+
+// Parse a bytea value received from the server.  Both "hex" and the legacy
+// "escape" format are supported.
+func parseBytea(s []byte) (result []byte, err error) {
+	if len(s) >= 2 && bytes.Equal(s[:2], []byte("\\x")) {
+		// bytea_output = hex
+		s = s[2:] // trim off leading "\\x"
+		result = make([]byte, hex.DecodedLen(len(s)))
+		_, err := hex.Decode(result, s)
+		if err != nil {
+			return nil, err
+		}
+	} else {
+		// bytea_output = escape
+		for len(s) > 0 {
+			if s[0] == '\\' {
+				// escaped '\\'
+				if len(s) >= 2 && s[1] == '\\' {
+					result = append(result, '\\')
+					s = s[2:]
+					continue
+				}
+
+				// '\\' followed by an octal number
+				if len(s) < 4 {
+					return nil, fmt.Errorf("invalid bytea sequence %v", s)
+				}
+				r, err := strconv.ParseUint(string(s[1:4]), 8, 8)
+				if err != nil {
+					return nil, fmt.Errorf("could not parse bytea value: %s", err.Error())
+				}
+				result = append(result, byte(r))
+				s = s[4:]
+			} else {
+				// We hit an unescaped, raw byte.  Try to read in as many as
+				// possible in one go.
+				i := bytes.IndexByte(s, '\\')
+				if i == -1 {
+					result = append(result, s...)
+					break
+				}
+				result = append(result, s[:i]...)
+				s = s[i:]
+			}
+		}
+	}
+
+	return result, nil
+}
+
+func encodeBytea(serverVersion int, v []byte) (result []byte) {
+	if serverVersion >= 90000 {
+		// Use the hex format if we know that the server supports it
+		result = make([]byte, 2+hex.EncodedLen(len(v)))
+		result[0] = '\\'
+		result[1] = 'x'
+		hex.Encode(result[2:], v)
+	} else {
+		// .. or resort to "escape"
+		for _, b := range v {
+			if b == '\\' {
+				result = append(result, '\\', '\\')
+			} else if b < 0x20 || b > 0x7e {
+				result = append(result, []byte(fmt.Sprintf("\\%03o", b))...)
+			} else {
+				result = append(result, b)
+			}
+		}
+	}
+
+	return result
+}
+
+// NullTime represents a time.Time that may be null. NullTime implements the
+// sql.Scanner interface so it can be used as a scan destination, similar to
+// sql.NullString.
+type NullTime struct {
+	Time  time.Time
+	Valid bool // Valid is true if Time is not NULL
+}
+
+// Scan implements the Scanner interface.
+func (nt *NullTime) Scan(value interface{}) error {
+	nt.Time, nt.Valid = value.(time.Time)
+	return nil
+}
+
+// Value implements the driver Valuer interface.
+func (nt NullTime) Value() (driver.Value, error) {
+	if !nt.Valid {
+		return nil, nil
+	}
+	return nt.Time, nil
+}

vendor/github.com/lib/pq/error.go

@@ -0,0 +1,523 @@
+package pq
+
+import (
+	"database/sql/driver"
+	"fmt"
+	"io"
+	"net"
+	"runtime"
+)
+
+// Error severities
+const (
+	Efatal   = "FATAL"
+	Epanic   = "PANIC"
+	Ewarning = "WARNING"
+	Enotice  = "NOTICE"
+	Edebug   = "DEBUG"
+	Einfo    = "INFO"
+	Elog     = "LOG"
+)
+
+// Error represents an error communicating with the server.
+//
+// See http://www.postgresql.org/docs/current/static/protocol-error-fields.html for details of the fields
+type Error struct {
+	Severity         string
+	Code             ErrorCode
+	Message          string
+	Detail           string
+	Hint             string
+	Position         string
+	InternalPosition string
+	InternalQuery    string
+	Where            string
+	Schema           string
+	Table            string
+	Column           string
+	DataTypeName     string
+	Constraint       string
+	File             string
+	Line             string
+	Routine          string
+}
+
+// ErrorCode is a five-character error code.
+type ErrorCode string
+
+// Name returns a more human friendly rendering of the error code, namely the
+// "condition name".
+//
+// See http://www.postgresql.org/docs/9.3/static/errcodes-appendix.html for
+// details.
+func (ec ErrorCode) Name() string {
+	return errorCodeNames[ec]
+}
+
+// ErrorClass is only the class part of an error code.
+type ErrorClass string
+
+// Name returns the condition name of an error class.  It is equivalent to the
+// condition name of the "standard" error code (i.e. the one having the last
+// three characters "000").
+func (ec ErrorClass) Name() string {
+	return errorCodeNames[ErrorCode(ec+"000")]
+}
+
+// Class returns the error class, e.g. "28".
+//
+// See http://www.postgresql.org/docs/9.3/static/errcodes-appendix.html for
+// details.
+func (ec ErrorCode) Class() ErrorClass {
+	return ErrorClass(ec[0:2])
+}
+
+// errorCodeNames is a mapping between the five-character error codes and the
+// human readable "condition names". It is derived from the list at
+// http://www.postgresql.org/docs/9.3/static/errcodes-appendix.html
+var errorCodeNames = map[ErrorCode]string{
+	// Class 00 - Successful Completion
+	"00000": "successful_completion",
+	// Class 01 - Warning
+	"01000": "warning",
+	"0100C": "dynamic_result_sets_returned",
+	"01008": "implicit_zero_bit_padding",
+	"01003": "null_value_eliminated_in_set_function",
+	"01007": "privilege_not_granted",
+	"01006": "privilege_not_revoked",
+	"01004": "string_data_right_truncation",
+	"01P01": "deprecated_feature",
+	// Class 02 - No Data (this is also a warning class per the SQL standard)
+	"02000": "no_data",
+	"02001": "no_additional_dynamic_result_sets_returned",
+	// Class 03 - SQL Statement Not Yet Complete
+	"03000": "sql_statement_not_yet_complete",
+	// Class 08 - Connection Exception
+	"08000": "connection_exception",
+	"08003": "connection_does_not_exist",
+	"08006": "connection_failure",
+	"08001": "sqlclient_unable_to_establish_sqlconnection",
+	"08004": "sqlserver_rejected_establishment_of_sqlconnection",
+	"08007": "transaction_resolution_unknown",
+	"08P01": "protocol_violation",
+	// Class 09 - Triggered Action Exception
+	"09000": "triggered_action_exception",
+	// Class 0A - Feature Not Supported
+	"0A000": "feature_not_supported",
+	// Class 0B - Invalid Transaction Initiation
+	"0B000": "invalid_transaction_initiation",
+	// Class 0F - Locator Exception
+	"0F000": "locator_exception",
+	"0F001": "invalid_locator_specification",
+	// Class 0L - Invalid Grantor
+	"0L000": "invalid_grantor",
+	"0LP01": "invalid_grant_operation",
+	// Class 0P - Invalid Role Specification
+	"0P000": "invalid_role_specification",
+	// Class 0Z - Diagnostics Exception
+	"0Z000": "diagnostics_exception",
+	"0Z002": "stacked_diagnostics_accessed_without_active_handler",
+	// Class 20 - Case Not Found
+	"20000": "case_not_found",
+	// Class 21 - Cardinality Violation
+	"21000": "cardinality_violation",
+	// Class 22 - Data Exception
+	"22000": "data_exception",
+	"2202E": "array_subscript_error",
+	"22021": "character_not_in_repertoire",
+	"22008": "datetime_field_overflow",
+	"22012": "division_by_zero",
+	"22005": "error_in_assignment",
+	"2200B": "escape_character_conflict",
+	"22022": "indicator_overflow",
+	"22015": "interval_field_overflow",
+	"2201E": "invalid_argument_for_logarithm",
+	"22014": "invalid_argument_for_ntile_function",
+	"22016": "invalid_argument_for_nth_value_function",
+	"2201F": "invalid_argument_for_power_function",
+	"2201G": "invalid_argument_for_width_bucket_function",
+	"22018": "invalid_character_value_for_cast",
+	"22007": "invalid_datetime_format",
+	"22019": "invalid_escape_character",
+	"2200D": "invalid_escape_octet",
+	"22025": "invalid_escape_sequence",
+	"22P06": "nonstandard_use_of_escape_character",
+	"22010": "invalid_indicator_parameter_value",
+	"22023": "invalid_parameter_value",
+	"2201B": "invalid_regular_expression",
+	"2201W": "invalid_row_count_in_limit_clause",
+	"2201X": "invalid_row_count_in_result_offset_clause",
+	"22009": "invalid_time_zone_displacement_value",
+	"2200C": "invalid_use_of_escape_character",
+	"2200G": "most_specific_type_mismatch",
+	"22004": "null_value_not_allowed",
+	"22002": "null_value_no_indicator_parameter",
+	"22003": "numeric_value_out_of_range",
+	"2200H": "sequence_generator_limit_exceeded",
+	"22026": "string_data_length_mismatch",
+	"22001": "string_data_right_truncation",
+	"22011": "substring_error",
+	"22027": "trim_error",
+	"22024": "unterminated_c_string",
+	"2200F": "zero_length_character_string",
+	"22P01": "floating_point_exception",
+	"22P02": "invalid_text_representation",
+	"22P03": "invalid_binary_representation",
+	"22P04": "bad_copy_file_format",
+	"22P05": "untranslatable_character",
+	"2200L": "not_an_xml_document",
+	"2200M": "invalid_xml_document",
+	"2200N": "invalid_xml_content",
+	"2200S": "invalid_xml_comment",
+	"2200T": "invalid_xml_processing_instruction",
+	// Class 23 - Integrity Constraint Violation
+	"23000": "integrity_constraint_violation",
+	"23001": "restrict_violation",
+	"23502": "not_null_violation",
+	"23503": "foreign_key_violation",
+	"23505": "unique_violation",
+	"23514": "check_violation",
+	"23P01": "exclusion_violation",
+	// Class 24 - Invalid Cursor State
+	"24000": "invalid_cursor_state",
+	// Class 25 - Invalid Transaction State
+	"25000": "invalid_transaction_state",
+	"25001": "active_sql_transaction",
+	"25002": "branch_transaction_already_active",
+	"25008": "held_cursor_requires_same_isolation_level",
+	"25003": "inappropriate_access_mode_for_branch_transaction",
+	"25004": "inappropriate_isolation_level_for_branch_transaction",
+	"25005": "no_active_sql_transaction_for_branch_transaction",
+	"25006": "read_only_sql_transaction",
+	"25007": "schema_and_data_statement_mixing_not_supported",
+	"25P01": "no_active_sql_transaction",
+	"25P02": "in_failed_sql_transaction",
+	// Class 26 - Invalid SQL Statement Name
+	"26000": "invalid_sql_statement_name",
+	// Class 27 - Triggered Data Change Violation
+	"27000": "triggered_data_change_violation",
+	// Class 28 - Invalid Authorization Specification
+	"28000": "invalid_authorization_specification",
+	"28P01": "invalid_password",
+	// Class 2B - Dependent Privilege Descriptors Still Exist
+	"2B000": "dependent_privilege_descriptors_still_exist",
+	"2BP01": "dependent_objects_still_exist",
+	// Class 2D - Invalid Transaction Termination
+	"2D000": "invalid_transaction_termination",
+	// Class 2F - SQL Routine Exception
+	"2F000": "sql_routine_exception",
+	"2F005": "function_executed_no_return_statement",
+	"2F002": "modifying_sql_data_not_permitted",
+	"2F003": "prohibited_sql_statement_attempted",
+	"2F004": "reading_sql_data_not_permitted",
+	// Class 34 - Invalid Cursor Name
+	"34000": "invalid_cursor_name",
+	// Class 38 - External Routine Exception
+	"38000": "external_routine_exception",
+	"38001": "containing_sql_not_permitted",
+	"38002": "modifying_sql_data_not_permitted",
+	"38003": "prohibited_sql_statement_attempted",
+	"38004": "reading_sql_data_not_permitted",
+	// Class 39 - External Routine Invocation Exception
+	"39000": "external_routine_invocation_exception",
+	"39001": "invalid_sqlstate_returned",
+	"39004": "null_value_not_allowed",
+	"39P01": "trigger_protocol_violated",
+	"39P02": "srf_protocol_violated",
+	// Class 3B - Savepoint Exception
+	"3B000": "savepoint_exception",
+	"3B001": "invalid_savepoint_specification",
+	// Class 3D - Invalid Catalog Name
+	"3D000": "invalid_catalog_name",
+	// Class 3F - Invalid Schema Name
+	"3F000": "invalid_schema_name",
+	// Class 40 - Transaction Rollback
+	"40000": "transaction_rollback",
+	"40002": "transaction_integrity_constraint_violation",
+	"40001": "serialization_failure",
+	"40003": "statement_completion_unknown",
+	"40P01": "deadlock_detected",
+	// Class 42 - Syntax Error or Access Rule Violation
+	"42000": "syntax_error_or_access_rule_violation",
+	"42601": "syntax_error",
+	"42501": "insufficient_privilege",
+	"42846": "cannot_coerce",
+	"42803": "grouping_error",
+	"42P20": "windowing_error",
+	"42P19": "invalid_recursion",
+	"42830": "invalid_foreign_key",
+	"42602": "invalid_name",
+	"42622": "name_too_long",
+	"42939": "reserved_name",
+	"42804": "datatype_mismatch",
+	"42P18": "indeterminate_datatype",
+	"42P21": "collation_mismatch",
+	"42P22": "indeterminate_collation",
+	"42809": "wrong_object_type",
+	"42703": "undefined_column",
+	"42883": "undefined_function",
+	"42P01": "undefined_table",
+	"42P02": "undefined_parameter",
+	"42704": "undefined_object",
+	"42701": "duplicate_column",
+	"42P03": "duplicate_cursor",
+	"42P04": "duplicate_database",
+	"42723": "duplicate_function",
+	"42P05": "duplicate_prepared_statement",
+	"42P06": "duplicate_schema",
+	"42P07": "duplicate_table",
+	"42712": "duplicate_alias",
+	"42710": "duplicate_object",
+	"42702": "ambiguous_column",
+	"42725": "ambiguous_function",
+	"42P08": "ambiguous_parameter",
+	"42P09": "ambiguous_alias",
+	"42P10": "invalid_column_reference",
+	"42611": "invalid_column_definition",
+	"42P11": "invalid_cursor_definition",
+	"42P12": "invalid_database_definition",
+	"42P13": "invalid_function_definition",
+	"42P14": "invalid_prepared_statement_definition",
+	"42P15": "invalid_schema_definition",
+	"42P16": "invalid_table_definition",
+	"42P17": "invalid_object_definition",
+	// Class 44 - WITH CHECK OPTION Violation
+	"44000": "with_check_option_violation",
+	// Class 53 - Insufficient Resources
+	"53000": "insufficient_resources",
+	"53100": "disk_full",
+	"53200": "out_of_memory",
+	"53300": "too_many_connections",
+	"53400": "configuration_limit_exceeded",
+	// Class 54 - Program Limit Exceeded
+	"54000": "program_limit_exceeded",
+	"54001": "statement_too_complex",
+	"54011": "too_many_columns",
+	"54023": "too_many_arguments",
+	// Class 55 - Object Not In Prerequisite State
+	"55000": "object_not_in_prerequisite_state",
+	"55006": "object_in_use",
+	"55P02": "cant_change_runtime_param",
+	"55P03": "lock_not_available",
+	// Class 57 - Operator Intervention
+	"57000": "operator_intervention",
+	"57014": "query_canceled",
+	"57P01": "admin_shutdown",
+	"57P02": "crash_shutdown",
+	"57P03": "cannot_connect_now",
+	"57P04": "database_dropped",
+	// Class 58 - System Error (errors external to PostgreSQL itself)
+	"58000": "system_error",
+	"58030": "io_error",
+	"58P01": "undefined_file",
+	"58P02": "duplicate_file",
+	// Class F0 - Configuration File Error
+	"F0000": "config_file_error",
+	"F0001": "lock_file_exists",
+	// Class HV - Foreign Data Wrapper Error (SQL/MED)
+	"HV000": "fdw_error",
+	"HV005": "fdw_column_name_not_found",
+	"HV002": "fdw_dynamic_parameter_value_needed",
+	"HV010": "fdw_function_sequence_error",
+	"HV021": "fdw_inconsistent_descriptor_information",
+	"HV024": "fdw_invalid_attribute_value",
+	"HV007": "fdw_invalid_column_name",
+	"HV008": "fdw_invalid_column_number",
+	"HV004": "fdw_invalid_data_type",
+	"HV006": "fdw_invalid_data_type_descriptors",
+	"HV091": "fdw_invalid_descriptor_field_identifier",
+	"HV00B": "fdw_invalid_handle",
+	"HV00C": "fdw_invalid_option_index",
+	"HV00D": "fdw_invalid_option_name",
+	"HV090": "fdw_invalid_string_length_or_buffer_length",
+	"HV00A": "fdw_invalid_string_format",
+	"HV009": "fdw_invalid_use_of_null_pointer",
+	"HV014": "fdw_too_many_handles",
+	"HV001": "fdw_out_of_memory",
+	"HV00P": "fdw_no_schemas",
+	"HV00J": "fdw_option_name_not_found",
+	"HV00K": "fdw_reply_handle",
+	"HV00Q": "fdw_schema_not_found",
+	"HV00R": "fdw_table_not_found",
+	"HV00L": "fdw_unable_to_create_execution",
+	"HV00M": "fdw_unable_to_create_reply",
+	"HV00N": "fdw_unable_to_establish_connection",
+	// Class P0 - PL/pgSQL Error
+	"P0000": "plpgsql_error",
+	"P0001": "raise_exception",
+	"P0002": "no_data_found",
+	"P0003": "too_many_rows",
+	// Class XX - Internal Error
+	"XX000": "internal_error",
+	"XX001": "data_corrupted",
+	"XX002": "index_corrupted",
+}
+
+func parseError(r *readBuf) *Error {
+	err := new(Error)
+	for t := r.byte(); t != 0; t = r.byte() {
+		msg := r.string()
+		switch t {
+		case 'S':
+			err.Severity = msg
+		case 'C':
+			err.Code = ErrorCode(msg)
+		case 'M':
+			err.Message = msg
+		case 'D':
+			err.Detail = msg
+		case 'H':
+			err.Hint = msg
+		case 'P':
+			err.Position = msg
+		case 'p':
+			err.InternalPosition = msg
+		case 'q':
+			err.InternalQuery = msg
+		case 'W':
+			err.Where = msg
+		case 's':
+			err.Schema = msg
+		case 't':
+			err.Table = msg
+		case 'c':
+			err.Column = msg
+		case 'd':
+			err.DataTypeName = msg
+		case 'n':
+			err.Constraint = msg
+		case 'F':
+			err.File = msg
+		case 'L':
+			err.Line = msg
+		case 'R':
+			err.Routine = msg
+		}
+	}
+	return err
+}
+
+// Fatal returns true if the Error Severity is fatal.
+func (err *Error) Fatal() bool {
+	return err.Severity == Efatal
+}
+
+// SQLState returns the SQLState of the error.
+func (err *Error) SQLState() string {
+	return string(err.Code)
+}
+
+// Get implements the legacy PGError interface. New code should use the fields
+// of the Error struct directly.
+func (err *Error) Get(k byte) (v string) {
+	switch k {
+	case 'S':
+		return err.Severity
+	case 'C':
+		return string(err.Code)
+	case 'M':
+		return err.Message
+	case 'D':
+		return err.Detail
+	case 'H':
+		return err.Hint
+	case 'P':
+		return err.Position
+	case 'p':
+		return err.InternalPosition
+	case 'q':
+		return err.InternalQuery
+	case 'W':
+		return err.Where
+	case 's':
+		return err.Schema
+	case 't':
+		return err.Table
+	case 'c':
+		return err.Column
+	case 'd':
+		return err.DataTypeName
+	case 'n':
+		return err.Constraint
+	case 'F':
+		return err.File
+	case 'L':
+		return err.Line
+	case 'R':
+		return err.Routine
+	}
+	return ""
+}
+
+func (err *Error) Error() string {
+	return "pq: " + err.Message
+}
+
+// PGError is an interface used by previous versions of pq. It is provided
+// only to support legacy code. New code should use the Error type.
+type PGError interface {
+	Error() string
+	Fatal() bool
+	Get(k byte) (v string)
+}
+
+func errorf(s string, args ...interface{}) {
+	panic(fmt.Errorf("pq: %s", fmt.Sprintf(s, args...)))
+}
+
+// TODO(ainar-g) Rename to errorf after removing panics.
+func fmterrorf(s string, args ...interface{}) error {
+	return fmt.Errorf("pq: %s", fmt.Sprintf(s, args...))
+}
+
+func errRecoverNoErrBadConn(err *error) {
+	e := recover()
+	if e == nil {
+		// Do nothing
+		return
+	}
+	var ok bool
+	*err, ok = e.(error)
+	if !ok {
+		*err = fmt.Errorf("pq: unexpected error: %#v", e)
+	}
+}
+
+func (cn *conn) errRecover(err *error) {
+	e := recover()
+	switch v := e.(type) {
+	case nil:
+		// Do nothing
+	case runtime.Error:
+		cn.err.set(driver.ErrBadConn)
+		panic(v)
+	case *Error:
+		if v.Fatal() {
+			*err = driver.ErrBadConn
+		} else {
+			*err = v
+		}
+	case *net.OpError:
+		cn.err.set(driver.ErrBadConn)
+		*err = v
+	case *safeRetryError:
+		cn.err.set(driver.ErrBadConn)
+		*err = driver.ErrBadConn
+	case error:
+		if v == io.EOF || v.Error() == "remote error: handshake failure" {
+			*err = driver.ErrBadConn
+		} else {
+			*err = v
+		}
+
+	default:
+		cn.err.set(driver.ErrBadConn)
+		panic(fmt.Sprintf("unknown error: %#v", e))
+	}
+
+	// Any time we return ErrBadConn, we need to remember it since *Tx doesn't
+	// mark the connection bad in database/sql.
+	if *err == driver.ErrBadConn {
+		cn.err.set(driver.ErrBadConn)
+	}
+}

vendor/github.com/lib/pq/krb.go

@@ -0,0 +1,27 @@
+package pq
+
+// NewGSSFunc creates a GSS authentication provider, for use with
+// RegisterGSSProvider.
+type NewGSSFunc func() (GSS, error)
+
+var newGss NewGSSFunc
+
+// RegisterGSSProvider registers a GSS authentication provider. For example, if
+// you need to use Kerberos to authenticate with your server, add this to your
+// main package:
+//
+//	import "github.com/lib/pq/auth/kerberos"
+//
+//	func init() {
+//		pq.RegisterGSSProvider(func() (pq.GSS, error) { return kerberos.NewGSS() })
+//	}
+func RegisterGSSProvider(newGssArg NewGSSFunc) {
+	newGss = newGssArg
+}
+
+// GSS provides GSSAPI authentication (e.g., Kerberos).
+type GSS interface {
+	GetInitToken(host string, service string) ([]byte, error)
+	GetInitTokenFromSpn(spn string) ([]byte, error)
+	Continue(inToken []byte) (done bool, outToken []byte, err error)
+}

vendor/github.com/lib/pq/notice.go

@@ -0,0 +1,72 @@
+//go:build go1.10
+// +build go1.10
+
+package pq
+
+import (
+	"context"
+	"database/sql/driver"
+)
+
+// NoticeHandler returns the notice handler on the given connection, if any. A
+// runtime panic occurs if c is not a pq connection. This is rarely used
+// directly, use ConnectorNoticeHandler and ConnectorWithNoticeHandler instead.
+func NoticeHandler(c driver.Conn) func(*Error) {
+	return c.(*conn).noticeHandler
+}
+
+// SetNoticeHandler sets the given notice handler on the given connection. A
+// runtime panic occurs if c is not a pq connection. A nil handler may be used
+// to unset it. This is rarely used directly, use ConnectorNoticeHandler and
+// ConnectorWithNoticeHandler instead.
+//
+// Note: Notice handlers are executed synchronously by pq meaning commands
+// won't continue to be processed until the handler returns.
+func SetNoticeHandler(c driver.Conn, handler func(*Error)) {
+	c.(*conn).noticeHandler = handler
+}
+
+// NoticeHandlerConnector wraps a regular connector and sets a notice handler
+// on it.
+type NoticeHandlerConnector struct {
+	driver.Connector
+	noticeHandler func(*Error)
+}
+
+// Connect calls the underlying connector's connect method and then sets the
+// notice handler.
+func (n *NoticeHandlerConnector) Connect(ctx context.Context) (driver.Conn, error) {
+	c, err := n.Connector.Connect(ctx)
+	if err == nil {
+		SetNoticeHandler(c, n.noticeHandler)
+	}
+	return c, err
+}
+
+// ConnectorNoticeHandler returns the currently set notice handler, if any. If
+// the given connector is not a result of ConnectorWithNoticeHandler, nil is
+// returned.
+func ConnectorNoticeHandler(c driver.Connector) func(*Error) {
+	if c, ok := c.(*NoticeHandlerConnector); ok {
+		return c.noticeHandler
+	}
+	return nil
+}
+
+// ConnectorWithNoticeHandler creates or sets the given handler for the given
+// connector. If the given connector is a result of calling this function
+// previously, it is simply set on the given connector and returned. Otherwise,
+// this returns a new connector wrapping the given one and setting the notice
+// handler. A nil notice handler may be used to unset it.
+//
+// The returned connector is intended to be used with database/sql.OpenDB.
+//
+// Note: Notice handlers are executed synchronously by pq meaning commands
+// won't continue to be processed until the handler returns.
+func ConnectorWithNoticeHandler(c driver.Connector, handler func(*Error)) *NoticeHandlerConnector {
+	if c, ok := c.(*NoticeHandlerConnector); ok {
+		c.noticeHandler = handler
+		return c
+	}
+	return &NoticeHandlerConnector{Connector: c, noticeHandler: handler}
+}

vendor/github.com/lib/pq/notify.go

@@ -0,0 +1,858 @@
+package pq
+
+// Package pq is a pure Go Postgres driver for the database/sql package.
+// This module contains support for Postgres LISTEN/NOTIFY.
+
+import (
+	"context"
+	"database/sql/driver"
+	"errors"
+	"fmt"
+	"sync"
+	"sync/atomic"
+	"time"
+)
+
+// Notification represents a single notification from the database.
+type Notification struct {
+	// Process ID (PID) of the notifying postgres backend.
+	BePid int
+	// Name of the channel the notification was sent on.
+	Channel string
+	// Payload, or the empty string if unspecified.
+	Extra string
+}
+
+func recvNotification(r *readBuf) *Notification {
+	bePid := r.int32()
+	channel := r.string()
+	extra := r.string()
+
+	return &Notification{bePid, channel, extra}
+}
+
+// SetNotificationHandler sets the given notification handler on the given
+// connection. A runtime panic occurs if c is not a pq connection. A nil handler
+// may be used to unset it.
+//
+// Note: Notification handlers are executed synchronously by pq meaning commands
+// won't continue to be processed until the handler returns.
+func SetNotificationHandler(c driver.Conn, handler func(*Notification)) {
+	c.(*conn).notificationHandler = handler
+}
+
+// NotificationHandlerConnector wraps a regular connector and sets a notification handler
+// on it.
+type NotificationHandlerConnector struct {
+	driver.Connector
+	notificationHandler func(*Notification)
+}
+
+// Connect calls the underlying connector's connect method and then sets the
+// notification handler.
+func (n *NotificationHandlerConnector) Connect(ctx context.Context) (driver.Conn, error) {
+	c, err := n.Connector.Connect(ctx)
+	if err == nil {
+		SetNotificationHandler(c, n.notificationHandler)
+	}
+	return c, err
+}
+
+// ConnectorNotificationHandler returns the currently set notification handler, if any. If
+// the given connector is not a result of ConnectorWithNotificationHandler, nil is
+// returned.
+func ConnectorNotificationHandler(c driver.Connector) func(*Notification) {
+	if c, ok := c.(*NotificationHandlerConnector); ok {
+		return c.notificationHandler
+	}
+	return nil
+}
+
+// ConnectorWithNotificationHandler creates or sets the given handler for the given
+// connector. If the given connector is a result of calling this function
+// previously, it is simply set on the given connector and returned. Otherwise,
+// this returns a new connector wrapping the given one and setting the notification
+// handler. A nil notification handler may be used to unset it.
+//
+// The returned connector is intended to be used with database/sql.OpenDB.
+//
+// Note: Notification handlers are executed synchronously by pq meaning commands
+// won't continue to be processed until the handler returns.
+func ConnectorWithNotificationHandler(c driver.Connector, handler func(*Notification)) *NotificationHandlerConnector {
+	if c, ok := c.(*NotificationHandlerConnector); ok {
+		c.notificationHandler = handler
+		return c
+	}
+	return &NotificationHandlerConnector{Connector: c, notificationHandler: handler}
+}
+
+const (
+	connStateIdle int32 = iota
+	connStateExpectResponse
+	connStateExpectReadyForQuery
+)
+
+type message struct {
+	typ byte
+	err error
+}
+
+var errListenerConnClosed = errors.New("pq: ListenerConn has been closed")
+
+// ListenerConn is a low-level interface for waiting for notifications.  You
+// should use Listener instead.
+type ListenerConn struct {
+	// guards cn and err
+	connectionLock sync.Mutex
+	cn             *conn
+	err            error
+
+	connState int32
+
+	// the sending goroutine will be holding this lock
+	senderLock sync.Mutex
+
+	notificationChan chan<- *Notification
+
+	replyChan chan message
+}
+
+// NewListenerConn creates a new ListenerConn. Use NewListener instead.
+func NewListenerConn(name string, notificationChan chan<- *Notification) (*ListenerConn, error) {
+	return newDialListenerConn(defaultDialer{}, name, notificationChan)
+}
+
+func newDialListenerConn(d Dialer, name string, c chan<- *Notification) (*ListenerConn, error) {
+	cn, err := DialOpen(d, name)
+	if err != nil {
+		return nil, err
+	}
+
+	l := &ListenerConn{
+		cn:               cn.(*conn),
+		notificationChan: c,
+		connState:        connStateIdle,
+		replyChan:        make(chan message, 2),
+	}
+
+	go l.listenerConnMain()
+
+	return l, nil
+}
+
+// We can only allow one goroutine at a time to be running a query on the
+// connection for various reasons, so the goroutine sending on the connection
+// must be holding senderLock.
+//
+// Returns an error if an unrecoverable error has occurred and the ListenerConn
+// should be abandoned.
+func (l *ListenerConn) acquireSenderLock() error {
+	// we must acquire senderLock first to avoid deadlocks; see ExecSimpleQuery
+	l.senderLock.Lock()
+
+	l.connectionLock.Lock()
+	err := l.err
+	l.connectionLock.Unlock()
+	if err != nil {
+		l.senderLock.Unlock()
+		return err
+	}
+	return nil
+}
+
+func (l *ListenerConn) releaseSenderLock() {
+	l.senderLock.Unlock()
+}
+
+// setState advances the protocol state to newState.  Returns false if moving
+// to that state from the current state is not allowed.
+func (l *ListenerConn) setState(newState int32) bool {
+	var expectedState int32
+
+	switch newState {
+	case connStateIdle:
+		expectedState = connStateExpectReadyForQuery
+	case connStateExpectResponse:
+		expectedState = connStateIdle
+	case connStateExpectReadyForQuery:
+		expectedState = connStateExpectResponse
+	default:
+		panic(fmt.Sprintf("unexpected listenerConnState %d", newState))
+	}
+
+	return atomic.CompareAndSwapInt32(&l.connState, expectedState, newState)
+}
+
+// Main logic is here: receive messages from the postgres backend, forward
+// notifications and query replies and keep the internal state in sync with the
+// protocol state.  Returns when the connection has been lost, is about to go
+// away or should be discarded because we couldn't agree on the state with the
+// server backend.
+func (l *ListenerConn) listenerConnLoop() (err error) {
+	defer errRecoverNoErrBadConn(&err)
+
+	r := &readBuf{}
+	for {
+		t, err := l.cn.recvMessage(r)
+		if err != nil {
+			return err
+		}
+
+		switch t {
+		case 'A':
+			// recvNotification copies all the data so we don't need to worry
+			// about the scratch buffer being overwritten.
+			l.notificationChan <- recvNotification(r)
+
+		case 'T', 'D':
+			// only used by tests; ignore
+
+		case 'E':
+			// We might receive an ErrorResponse even when not in a query; it
+			// is expected that the server will close the connection after
+			// that, but we should make sure that the error we display is the
+			// one from the stray ErrorResponse, not io.ErrUnexpectedEOF.
+			if !l.setState(connStateExpectReadyForQuery) {
+				return parseError(r)
+			}
+			l.replyChan <- message{t, parseError(r)}
+
+		case 'C', 'I':
+			if !l.setState(connStateExpectReadyForQuery) {
+				// protocol out of sync
+				return fmt.Errorf("unexpected CommandComplete")
+			}
+			// ExecSimpleQuery doesn't need to know about this message
+
+		case 'Z':
+			if !l.setState(connStateIdle) {
+				// protocol out of sync
+				return fmt.Errorf("unexpected ReadyForQuery")
+			}
+			l.replyChan <- message{t, nil}
+
+		case 'S':
+			// ignore
+		case 'N':
+			if n := l.cn.noticeHandler; n != nil {
+				n(parseError(r))
+			}
+		default:
+			return fmt.Errorf("unexpected message %q from server in listenerConnLoop", t)
+		}
+	}
+}
+
+// This is the main routine for the goroutine receiving on the database
+// connection.  Most of the main logic is in listenerConnLoop.
+func (l *ListenerConn) listenerConnMain() {
+	err := l.listenerConnLoop()
+
+	// listenerConnLoop terminated; we're done, but we still have to clean up.
+	// Make sure nobody tries to start any new queries by making sure the err
+	// pointer is set.  It is important that we do not overwrite its value; a
+	// connection could be closed by either this goroutine or one sending on
+	// the connection -- whoever closes the connection is assumed to have the
+	// more meaningful error message (as the other one will probably get
+	// net.errClosed), so that goroutine sets the error we expose while the
+	// other error is discarded.  If the connection is lost while two
+	// goroutines are operating on the socket, it probably doesn't matter which
+	// error we expose so we don't try to do anything more complex.
+	l.connectionLock.Lock()
+	if l.err == nil {
+		l.err = err
+	}
+	l.cn.Close()
+	l.connectionLock.Unlock()
+
+	// There might be a query in-flight; make sure nobody's waiting for a
+	// response to it, since there's not going to be one.
+	close(l.replyChan)
+
+	// let the listener know we're done
+	close(l.notificationChan)
+
+	// this ListenerConn is done
+}
+
+// Listen sends a LISTEN query to the server. See ExecSimpleQuery.
+func (l *ListenerConn) Listen(channel string) (bool, error) {
+	return l.ExecSimpleQuery("LISTEN " + QuoteIdentifier(channel))
+}
+
+// Unlisten sends an UNLISTEN query to the server. See ExecSimpleQuery.
+func (l *ListenerConn) Unlisten(channel string) (bool, error) {
+	return l.ExecSimpleQuery("UNLISTEN " + QuoteIdentifier(channel))
+}
+
+// UnlistenAll sends an `UNLISTEN *` query to the server. See ExecSimpleQuery.
+func (l *ListenerConn) UnlistenAll() (bool, error) {
+	return l.ExecSimpleQuery("UNLISTEN *")
+}
+
+// Ping the remote server to make sure it's alive.  Non-nil error means the
+// connection has failed and should be abandoned.
+func (l *ListenerConn) Ping() error {
+	sent, err := l.ExecSimpleQuery("")
+	if !sent {
+		return err
+	}
+	if err != nil {
+		// shouldn't happen
+		panic(err)
+	}
+	return nil
+}
+
+// Attempt to send a query on the connection.  Returns an error if sending the
+// query failed, and the caller should initiate closure of this connection.
+// The caller must be holding senderLock (see acquireSenderLock and
+// releaseSenderLock).
+func (l *ListenerConn) sendSimpleQuery(q string) (err error) {
+	defer errRecoverNoErrBadConn(&err)
+
+	// must set connection state before sending the query
+	if !l.setState(connStateExpectResponse) {
+		panic("two queries running at the same time")
+	}
+
+	// Can't use l.cn.writeBuf here because it uses the scratch buffer which
+	// might get overwritten by listenerConnLoop.
+	b := &writeBuf{
+		buf: []byte("Q\x00\x00\x00\x00"),
+		pos: 1,
+	}
+	b.string(q)
+	l.cn.send(b)
+
+	return nil
+}
+
+// ExecSimpleQuery executes a "simple query" (i.e. one with no bindable
+// parameters) on the connection. The possible return values are:
+//   1) "executed" is true; the query was executed to completion on the
+//      database server.  If the query failed, err will be set to the error
+//      returned by the database, otherwise err will be nil.
+//   2) If "executed" is false, the query could not be executed on the remote
+//      server.  err will be non-nil.
+//
+// After a call to ExecSimpleQuery has returned an executed=false value, the
+// connection has either been closed or will be closed shortly thereafter, and
+// all subsequently executed queries will return an error.
+func (l *ListenerConn) ExecSimpleQuery(q string) (executed bool, err error) {
+	if err = l.acquireSenderLock(); err != nil {
+		return false, err
+	}
+	defer l.releaseSenderLock()
+
+	err = l.sendSimpleQuery(q)
+	if err != nil {
+		// We can't know what state the protocol is in, so we need to abandon
+		// this connection.
+		l.connectionLock.Lock()
+		// Set the error pointer if it hasn't been set already; see
+		// listenerConnMain.
+		if l.err == nil {
+			l.err = err
+		}
+		l.connectionLock.Unlock()
+		l.cn.c.Close()
+		return false, err
+	}
+
+	// now we just wait for a reply..
+	for {
+		m, ok := <-l.replyChan
+		if !ok {
+			// We lost the connection to server, don't bother waiting for a
+			// a response.  err should have been set already.
+			l.connectionLock.Lock()
+			err := l.err
+			l.connectionLock.Unlock()
+			return false, err
+		}
+		switch m.typ {
+		case 'Z':
+			// sanity check
+			if m.err != nil {
+				panic("m.err != nil")
+			}
+			// done; err might or might not be set
+			return true, err
+
+		case 'E':
+			// sanity check
+			if m.err == nil {
+				panic("m.err == nil")
+			}
+			// server responded with an error; ReadyForQuery to follow
+			err = m.err
+
+		default:
+			return false, fmt.Errorf("unknown response for simple query: %q", m.typ)
+		}
+	}
+}
+
+// Close closes the connection.
+func (l *ListenerConn) Close() error {
+	l.connectionLock.Lock()
+	if l.err != nil {
+		l.connectionLock.Unlock()
+		return errListenerConnClosed
+	}
+	l.err = errListenerConnClosed
+	l.connectionLock.Unlock()
+	// We can't send anything on the connection without holding senderLock.
+	// Simply close the net.Conn to wake up everyone operating on it.
+	return l.cn.c.Close()
+}
+
+// Err returns the reason the connection was closed. It is not safe to call
+// this function until l.Notify has been closed.
+func (l *ListenerConn) Err() error {
+	return l.err
+}
+
+var errListenerClosed = errors.New("pq: Listener has been closed")
+
+// ErrChannelAlreadyOpen is returned from Listen when a channel is already
+// open.
+var ErrChannelAlreadyOpen = errors.New("pq: channel is already open")
+
+// ErrChannelNotOpen is returned from Unlisten when a channel is not open.
+var ErrChannelNotOpen = errors.New("pq: channel is not open")
+
+// ListenerEventType is an enumeration of listener event types.
+type ListenerEventType int
+
+const (
+	// ListenerEventConnected is emitted only when the database connection
+	// has been initially initialized. The err argument of the callback
+	// will always be nil.
+	ListenerEventConnected ListenerEventType = iota
+
+	// ListenerEventDisconnected is emitted after a database connection has
+	// been lost, either because of an error or because Close has been
+	// called. The err argument will be set to the reason the database
+	// connection was lost.
+	ListenerEventDisconnected
+
+	// ListenerEventReconnected is emitted after a database connection has
+	// been re-established after connection loss. The err argument of the
+	// callback will always be nil. After this event has been emitted, a
+	// nil pq.Notification is sent on the Listener.Notify channel.
+	ListenerEventReconnected
+
+	// ListenerEventConnectionAttemptFailed is emitted after a connection
+	// to the database was attempted, but failed. The err argument will be
+	// set to an error describing why the connection attempt did not
+	// succeed.
+	ListenerEventConnectionAttemptFailed
+)
+
+// EventCallbackType is the event callback type. See also ListenerEventType
+// constants' documentation.
+type EventCallbackType func(event ListenerEventType, err error)
+
+// Listener provides an interface for listening to notifications from a
+// PostgreSQL database.  For general usage information, see section
+// "Notifications".
+//
+// Listener can safely be used from concurrently running goroutines.
+type Listener struct {
+	// Channel for receiving notifications from the database.  In some cases a
+	// nil value will be sent.  See section "Notifications" above.
+	Notify chan *Notification
+
+	name                 string
+	minReconnectInterval time.Duration
+	maxReconnectInterval time.Duration
+	dialer               Dialer
+	eventCallback        EventCallbackType
+
+	lock                 sync.Mutex
+	isClosed             bool
+	reconnectCond        *sync.Cond
+	cn                   *ListenerConn
+	connNotificationChan <-chan *Notification
+	channels             map[string]struct{}
+}
+
+// NewListener creates a new database connection dedicated to LISTEN / NOTIFY.
+//
+// name should be set to a connection string to be used to establish the
+// database connection (see section "Connection String Parameters" above).
+//
+// minReconnectInterval controls the duration to wait before trying to
+// re-establish the database connection after connection loss.  After each
+// consecutive failure this interval is doubled, until maxReconnectInterval is
+// reached.  Successfully completing the connection establishment procedure
+// resets the interval back to minReconnectInterval.
+//
+// The last parameter eventCallback can be set to a function which will be
+// called by the Listener when the state of the underlying database connection
+// changes.  This callback will be called by the goroutine which dispatches the
+// notifications over the Notify channel, so you should try to avoid doing
+// potentially time-consuming operations from the callback.
+func NewListener(name string,
+	minReconnectInterval time.Duration,
+	maxReconnectInterval time.Duration,
+	eventCallback EventCallbackType) *Listener {
+	return NewDialListener(defaultDialer{}, name, minReconnectInterval, maxReconnectInterval, eventCallback)
+}
+
+// NewDialListener is like NewListener but it takes a Dialer.
+func NewDialListener(d Dialer,
+	name string,
+	minReconnectInterval time.Duration,
+	maxReconnectInterval time.Duration,
+	eventCallback EventCallbackType) *Listener {
+
+	l := &Listener{
+		name:                 name,
+		minReconnectInterval: minReconnectInterval,
+		maxReconnectInterval: maxReconnectInterval,
+		dialer:               d,
+		eventCallback:        eventCallback,
+
+		channels: make(map[string]struct{}),
+
+		Notify: make(chan *Notification, 32),
+	}
+	l.reconnectCond = sync.NewCond(&l.lock)
+
+	go l.listenerMain()
+
+	return l
+}
+
+// NotificationChannel returns the notification channel for this listener.
+// This is the same channel as Notify, and will not be recreated during the
+// life time of the Listener.
+func (l *Listener) NotificationChannel() <-chan *Notification {
+	return l.Notify
+}
+
+// Listen starts listening for notifications on a channel.  Calls to this
+// function will block until an acknowledgement has been received from the
+// server.  Note that Listener automatically re-establishes the connection
+// after connection loss, so this function may block indefinitely if the
+// connection can not be re-established.
+//
+// Listen will only fail in three conditions:
+//   1) The channel is already open.  The returned error will be
+//      ErrChannelAlreadyOpen.
+//   2) The query was executed on the remote server, but PostgreSQL returned an
+//      error message in response to the query.  The returned error will be a
+//      pq.Error containing the information the server supplied.
+//   3) Close is called on the Listener before the request could be completed.
+//
+// The channel name is case-sensitive.
+func (l *Listener) Listen(channel string) error {
+	l.lock.Lock()
+	defer l.lock.Unlock()
+
+	if l.isClosed {
+		return errListenerClosed
+	}
+
+	// The server allows you to issue a LISTEN on a channel which is already
+	// open, but it seems useful to be able to detect this case to spot for
+	// mistakes in application logic.  If the application genuinely does't
+	// care, it can check the exported error and ignore it.
+	_, exists := l.channels[channel]
+	if exists {
+		return ErrChannelAlreadyOpen
+	}
+
+	if l.cn != nil {
+		// If gotResponse is true but error is set, the query was executed on
+		// the remote server, but resulted in an error.  This should be
+		// relatively rare, so it's fine if we just pass the error to our
+		// caller.  However, if gotResponse is false, we could not complete the
+		// query on the remote server and our underlying connection is about
+		// to go away, so we only add relname to l.channels, and wait for
+		// resync() to take care of the rest.
+		gotResponse, err := l.cn.Listen(channel)
+		if gotResponse && err != nil {
+			return err
+		}
+	}
+
+	l.channels[channel] = struct{}{}
+	for l.cn == nil {
+		l.reconnectCond.Wait()
+		// we let go of the mutex for a while
+		if l.isClosed {
+			return errListenerClosed
+		}
+	}
+
+	return nil
+}
+
+// Unlisten removes a channel from the Listener's channel list.  Returns
+// ErrChannelNotOpen if the Listener is not listening on the specified channel.
+// Returns immediately with no error if there is no connection.  Note that you
+// might still get notifications for this channel even after Unlisten has
+// returned.
+//
+// The channel name is case-sensitive.
+func (l *Listener) Unlisten(channel string) error {
+	l.lock.Lock()
+	defer l.lock.Unlock()
+
+	if l.isClosed {
+		return errListenerClosed
+	}
+
+	// Similarly to LISTEN, this is not an error in Postgres, but it seems
+	// useful to distinguish from the normal conditions.
+	_, exists := l.channels[channel]
+	if !exists {
+		return ErrChannelNotOpen
+	}
+
+	if l.cn != nil {
+		// Similarly to Listen (see comment in that function), the caller
+		// should only be bothered with an error if it came from the backend as
+		// a response to our query.
+		gotResponse, err := l.cn.Unlisten(channel)
+		if gotResponse && err != nil {
+			return err
+		}
+	}
+
+	// Don't bother waiting for resync if there's no connection.
+	delete(l.channels, channel)
+	return nil
+}
+
+// UnlistenAll removes all channels from the Listener's channel list.  Returns
+// immediately with no error if there is no connection.  Note that you might
+// still get notifications for any of the deleted channels even after
+// UnlistenAll has returned.
+func (l *Listener) UnlistenAll() error {
+	l.lock.Lock()
+	defer l.lock.Unlock()
+
+	if l.isClosed {
+		return errListenerClosed
+	}
+
+	if l.cn != nil {
+		// Similarly to Listen (see comment in that function), the caller
+		// should only be bothered with an error if it came from the backend as
+		// a response to our query.
+		gotResponse, err := l.cn.UnlistenAll()
+		if gotResponse && err != nil {
+			return err
+		}
+	}
+
+	// Don't bother waiting for resync if there's no connection.
+	l.channels = make(map[string]struct{})
+	return nil
+}
+
+// Ping the remote server to make sure it's alive.  Non-nil return value means
+// that there is no active connection.
+func (l *Listener) Ping() error {
+	l.lock.Lock()
+	defer l.lock.Unlock()
+
+	if l.isClosed {
+		return errListenerClosed
+	}
+	if l.cn == nil {
+		return errors.New("no connection")
+	}
+
+	return l.cn.Ping()
+}
+
+// Clean up after losing the server connection.  Returns l.cn.Err(), which
+// should have the reason the connection was lost.
+func (l *Listener) disconnectCleanup() error {
+	l.lock.Lock()
+	defer l.lock.Unlock()
+
+	// sanity check; can't look at Err() until the channel has been closed
+	select {
+	case _, ok := <-l.connNotificationChan:
+		if ok {
+			panic("connNotificationChan not closed")
+		}
+	default:
+		panic("connNotificationChan not closed")
+	}
+
+	err := l.cn.Err()
+	l.cn.Close()
+	l.cn = nil
+	return err
+}
+
+// Synchronize the list of channels we want to be listening on with the server
+// after the connection has been established.
+func (l *Listener) resync(cn *ListenerConn, notificationChan <-chan *Notification) error {
+	doneChan := make(chan error)
+	go func(notificationChan <-chan *Notification) {
+		for channel := range l.channels {
+			// If we got a response, return that error to our caller as it's
+			// going to be more descriptive than cn.Err().
+			gotResponse, err := cn.Listen(channel)
+			if gotResponse && err != nil {
+				doneChan <- err
+				return
+			}
+
+			// If we couldn't reach the server, wait for notificationChan to
+			// close and then return the error message from the connection, as
+			// per ListenerConn's interface.
+			if err != nil {
+				for range notificationChan {
+				}
+				doneChan <- cn.Err()
+				return
+			}
+		}
+		doneChan <- nil
+	}(notificationChan)
+
+	// Ignore notifications while synchronization is going on to avoid
+	// deadlocks.  We have to send a nil notification over Notify anyway as
+	// we can't possibly know which notifications (if any) were lost while
+	// the connection was down, so there's no reason to try and process
+	// these messages at all.
+	for {
+		select {
+		case _, ok := <-notificationChan:
+			if !ok {
+				notificationChan = nil
+			}
+
+		case err := <-doneChan:
+			return err
+		}
+	}
+}
+
+// caller should NOT be holding l.lock
+func (l *Listener) closed() bool {
+	l.lock.Lock()
+	defer l.lock.Unlock()
+
+	return l.isClosed
+}
+
+func (l *Listener) connect() error {
+	notificationChan := make(chan *Notification, 32)
+	cn, err := newDialListenerConn(l.dialer, l.name, notificationChan)
+	if err != nil {
+		return err
+	}
+
+	l.lock.Lock()
+	defer l.lock.Unlock()
+
+	err = l.resync(cn, notificationChan)
+	if err != nil {
+		cn.Close()
+		return err
+	}
+
+	l.cn = cn
+	l.connNotificationChan = notificationChan
+	l.reconnectCond.Broadcast()
+
+	return nil
+}
+
+// Close disconnects the Listener from the database and shuts it down.
+// Subsequent calls to its methods will return an error.  Close returns an
+// error if the connection has already been closed.
+func (l *Listener) Close() error {
+	l.lock.Lock()
+	defer l.lock.Unlock()
+
+	if l.isClosed {
+		return errListenerClosed
+	}
+
+	if l.cn != nil {
+		l.cn.Close()
+	}
+	l.isClosed = true
+
+	// Unblock calls to Listen()
+	l.reconnectCond.Broadcast()
+
+	return nil
+}
+
+func (l *Listener) emitEvent(event ListenerEventType, err error) {
+	if l.eventCallback != nil {
+		l.eventCallback(event, err)
+	}
+}
+
+// Main logic here: maintain a connection to the server when possible, wait
+// for notifications and emit events.
+func (l *Listener) listenerConnLoop() {
+	var nextReconnect time.Time
+
+	reconnectInterval := l.minReconnectInterval
+	for {
+		for {
+			err := l.connect()
+			if err == nil {
+				break
+			}
+
+			if l.closed() {
+				return
+			}
+			l.emitEvent(ListenerEventConnectionAttemptFailed, err)
+
+			time.Sleep(reconnectInterval)
+			reconnectInterval *= 2
+			if reconnectInterval > l.maxReconnectInterval {
+				reconnectInterval = l.maxReconnectInterval
+			}
+		}
+
+		if nextReconnect.IsZero() {
+			l.emitEvent(ListenerEventConnected, nil)
+		} else {
+			l.emitEvent(ListenerEventReconnected, nil)
+			l.Notify <- nil
+		}
+
+		reconnectInterval = l.minReconnectInterval
+		nextReconnect = time.Now().Add(reconnectInterval)
+
+		for {
+			notification, ok := <-l.connNotificationChan
+			if !ok {
+				// lost connection, loop again
+				break
+			}
+			l.Notify <- notification
+		}
+
+		err := l.disconnectCleanup()
+		if l.closed() {
+			return
+		}
+		l.emitEvent(ListenerEventDisconnected, err)
+
+		time.Sleep(time.Until(nextReconnect))
+	}
+}
+
+func (l *Listener) listenerMain() {
+	l.listenerConnLoop()
+	close(l.Notify)
+}

vendor/github.com/lib/pq/oid/doc.go

@@ -0,0 +1,6 @@
+// Package oid contains OID constants
+// as defined by the Postgres server.
+package oid
+
+// Oid is a Postgres Object ID.
+type Oid uint32

vendor/github.com/lib/pq/oid/types.go

@@ -0,0 +1,343 @@
+// Code generated by gen.go. DO NOT EDIT.
+
+package oid
+
+const (
+	T_bool             Oid = 16
+	T_bytea            Oid = 17
+	T_char             Oid = 18
+	T_name             Oid = 19
+	T_int8             Oid = 20
+	T_int2             Oid = 21
+	T_int2vector       Oid = 22
+	T_int4             Oid = 23
+	T_regproc          Oid = 24
+	T_text             Oid = 25
+	T_oid              Oid = 26
+	T_tid              Oid = 27
+	T_xid              Oid = 28
+	T_cid              Oid = 29
+	T_oidvector        Oid = 30
+	T_pg_ddl_command   Oid = 32
+	T_pg_type          Oid = 71
+	T_pg_attribute     Oid = 75
+	T_pg_proc          Oid = 81
+	T_pg_class         Oid = 83
+	T_json             Oid = 114
+	T_xml              Oid = 142
+	T__xml             Oid = 143
+	T_pg_node_tree     Oid = 194
+	T__json            Oid = 199
+	T_smgr             Oid = 210
+	T_index_am_handler Oid = 325
+	T_point            Oid = 600
+	T_lseg             Oid = 601
+	T_path             Oid = 602
+	T_box              Oid = 603
+	T_polygon          Oid = 604
+	T_line             Oid = 628
+	T__line            Oid = 629
+	T_cidr             Oid = 650
+	T__cidr            Oid = 651
+	T_float4           Oid = 700
+	T_float8           Oid = 701
+	T_abstime          Oid = 702
+	T_reltime          Oid = 703
+	T_tinterval        Oid = 704
+	T_unknown          Oid = 705
+	T_circle           Oid = 718
+	T__circle          Oid = 719
+	T_money            Oid = 790
+	T__money           Oid = 791
+	T_macaddr          Oid = 829
+	T_inet             Oid = 869
+	T__bool            Oid = 1000
+	T__bytea           Oid = 1001
+	T__char            Oid = 1002
+	T__name            Oid = 1003
+	T__int2            Oid = 1005
+	T__int2vector      Oid = 1006
+	T__int4            Oid = 1007
+	T__regproc         Oid = 1008
+	T__text            Oid = 1009
+	T__tid             Oid = 1010
+	T__xid             Oid = 1011
+	T__cid             Oid = 1012
+	T__oidvector       Oid = 1013
+	T__bpchar          Oid = 1014
+	T__varchar         Oid = 1015
+	T__int8            Oid = 1016
+	T__point           Oid = 1017
+	T__lseg            Oid = 1018
+	T__path            Oid = 1019
+	T__box             Oid = 1020
+	T__float4          Oid = 1021
+	T__float8          Oid = 1022
+	T__abstime         Oid = 1023
+	T__reltime         Oid = 1024
+	T__tinterval       Oid = 1025
+	T__polygon         Oid = 1027
+	T__oid             Oid = 1028
+	T_aclitem          Oid = 1033
+	T__aclitem         Oid = 1034
+	T__macaddr         Oid = 1040
+	T__inet            Oid = 1041
+	T_bpchar           Oid = 1042
+	T_varchar          Oid = 1043
+	T_date             Oid = 1082
+	T_time             Oid = 1083
+	T_timestamp        Oid = 1114
+	T__timestamp       Oid = 1115
+	T__date            Oid = 1182
+	T__time            Oid = 1183
+	T_timestamptz      Oid = 1184
+	T__timestamptz     Oid = 1185
+	T_interval         Oid = 1186
+	T__interval        Oid = 1187
+	T__numeric         Oid = 1231
+	T_pg_database      Oid = 1248
+	T__cstring         Oid = 1263
+	T_timetz           Oid = 1266
+	T__timetz          Oid = 1270
+	T_bit              Oid = 1560
+	T__bit             Oid = 1561
+	T_varbit           Oid = 1562
+	T__varbit          Oid = 1563
+	T_numeric          Oid = 1700
+	T_refcursor        Oid = 1790
+	T__refcursor       Oid = 2201
+	T_regprocedure     Oid = 2202
+	T_regoper          Oid = 2203
+	T_regoperator      Oid = 2204
+	T_regclass         Oid = 2205
+	T_regtype          Oid = 2206
+	T__regprocedure    Oid = 2207
+	T__regoper         Oid = 2208
+	T__regoperator     Oid = 2209
+	T__regclass        Oid = 2210
+	T__regtype         Oid = 2211
+	T_record           Oid = 2249
+	T_cstring          Oid = 2275
+	T_any              Oid = 2276
+	T_anyarray         Oid = 2277
+	T_void             Oid = 2278
+	T_trigger          Oid = 2279
+	T_language_handler Oid = 2280
+	T_internal         Oid = 2281
+	T_opaque           Oid = 2282
+	T_anyelement       Oid = 2283
+	T__record          Oid = 2287
+	T_anynonarray      Oid = 2776
+	T_pg_authid        Oid = 2842
+	T_pg_auth_members  Oid = 2843
+	T__txid_snapshot   Oid = 2949
+	T_uuid             Oid = 2950
+	T__uuid            Oid = 2951
+	T_txid_snapshot    Oid = 2970
+	T_fdw_handler      Oid = 3115
+	T_pg_lsn           Oid = 3220
+	T__pg_lsn          Oid = 3221
+	T_tsm_handler      Oid = 3310
+	T_anyenum          Oid = 3500
+	T_tsvector         Oid = 3614
+	T_tsquery          Oid = 3615
+	T_gtsvector        Oid = 3642
+	T__tsvector        Oid = 3643
+	T__gtsvector       Oid = 3644
+	T__tsquery         Oid = 3645
+	T_regconfig        Oid = 3734
+	T__regconfig       Oid = 3735
+	T_regdictionary    Oid = 3769
+	T__regdictionary   Oid = 3770
+	T_jsonb            Oid = 3802
+	T__jsonb           Oid = 3807
+	T_anyrange         Oid = 3831
+	T_event_trigger    Oid = 3838
+	T_int4range        Oid = 3904
+	T__int4range       Oid = 3905
+	T_numrange         Oid = 3906
+	T__numrange        Oid = 3907
+	T_tsrange          Oid = 3908
+	T__tsrange         Oid = 3909
+	T_tstzrange        Oid = 3910
+	T__tstzrange       Oid = 3911
+	T_daterange        Oid = 3912
+	T__daterange       Oid = 3913
+	T_int8range        Oid = 3926
+	T__int8range       Oid = 3927
+	T_pg_shseclabel    Oid = 4066
+	T_regnamespace     Oid = 4089
+	T__regnamespace    Oid = 4090
+	T_regrole          Oid = 4096
+	T__regrole         Oid = 4097
+)
+
+var TypeName = map[Oid]string{
+	T_bool:             "BOOL",
+	T_bytea:            "BYTEA",
+	T_char:             "CHAR",
+	T_name:             "NAME",
+	T_int8:             "INT8",
+	T_int2:             "INT2",
+	T_int2vector:       "INT2VECTOR",
+	T_int4:             "INT4",
+	T_regproc:          "REGPROC",
+	T_text:             "TEXT",
+	T_oid:              "OID",
+	T_tid:              "TID",
+	T_xid:              "XID",
+	T_cid:              "CID",
+	T_oidvector:        "OIDVECTOR",
+	T_pg_ddl_command:   "PG_DDL_COMMAND",
+	T_pg_type:          "PG_TYPE",
+	T_pg_attribute:     "PG_ATTRIBUTE",
+	T_pg_proc:          "PG_PROC",
+	T_pg_class:         "PG_CLASS",
+	T_json:             "JSON",
+	T_xml:              "XML",
+	T__xml:             "_XML",
+	T_pg_node_tree:     "PG_NODE_TREE",
+	T__json:            "_JSON",
+	T_smgr:             "SMGR",
+	T_index_am_handler: "INDEX_AM_HANDLER",
+	T_point:            "POINT",
+	T_lseg:             "LSEG",
+	T_path:             "PATH",
+	T_box:              "BOX",
+	T_polygon:          "POLYGON",
+	T_line:             "LINE",
+	T__line:            "_LINE",
+	T_cidr:             "CIDR",
+	T__cidr:            "_CIDR",
+	T_float4:           "FLOAT4",
+	T_float8:           "FLOAT8",
+	T_abstime:          "ABSTIME",
+	T_reltime:          "RELTIME",
+	T_tinterval:        "TINTERVAL",
+	T_unknown:          "UNKNOWN",
+	T_circle:           "CIRCLE",
+	T__circle:          "_CIRCLE",
+	T_money:            "MONEY",
+	T__money:           "_MONEY",
+	T_macaddr:          "MACADDR",
+	T_inet:             "INET",
+	T__bool:            "_BOOL",
+	T__bytea:           "_BYTEA",
+	T__char:            "_CHAR",
+	T__name:            "_NAME",
+	T__int2:            "_INT2",
+	T__int2vector:      "_INT2VECTOR",
+	T__int4:            "_INT4",
+	T__regproc:         "_REGPROC",
+	T__text:            "_TEXT",
+	T__tid:             "_TID",
+	T__xid:             "_XID",
+	T__cid:             "_CID",
+	T__oidvector:       "_OIDVECTOR",
+	T__bpchar:          "_BPCHAR",
+	T__varchar:         "_VARCHAR",
+	T__int8:            "_INT8",
+	T__point:           "_POINT",
+	T__lseg:            "_LSEG",
+	T__path:            "_PATH",
+	T__box:             "_BOX",
+	T__float4:          "_FLOAT4",
+	T__float8:          "_FLOAT8",
+	T__abstime:         "_ABSTIME",
+	T__reltime:         "_RELTIME",
+	T__tinterval:       "_TINTERVAL",
+	T__polygon:         "_POLYGON",
+	T__oid:             "_OID",
+	T_aclitem:          "ACLITEM",
+	T__aclitem:         "_ACLITEM",
+	T__macaddr:         "_MACADDR",
+	T__inet:            "_INET",
+	T_bpchar:           "BPCHAR",
+	T_varchar:          "VARCHAR",
+	T_date:             "DATE",
+	T_time:             "TIME",
+	T_timestamp:        "TIMESTAMP",
+	T__timestamp:       "_TIMESTAMP",
+	T__date:            "_DATE",
+	T__time:            "_TIME",
+	T_timestamptz:      "TIMESTAMPTZ",
+	T__timestamptz:     "_TIMESTAMPTZ",
+	T_interval:         "INTERVAL",
+	T__interval:        "_INTERVAL",
+	T__numeric:         "_NUMERIC",
+	T_pg_database:      "PG_DATABASE",
+	T__cstring:         "_CSTRING",
+	T_timetz:           "TIMETZ",
+	T__timetz:          "_TIMETZ",
+	T_bit:              "BIT",
+	T__bit:             "_BIT",
+	T_varbit:           "VARBIT",
+	T__varbit:          "_VARBIT",
+	T_numeric:          "NUMERIC",
+	T_refcursor:        "REFCURSOR",
+	T__refcursor:       "_REFCURSOR",
+	T_regprocedure:     "REGPROCEDURE",
+	T_regoper:          "REGOPER",
+	T_regoperator:      "REGOPERATOR",
+	T_regclass:         "REGCLASS",
+	T_regtype:          "REGTYPE",
+	T__regprocedure:    "_REGPROCEDURE",
+	T__regoper:         "_REGOPER",
+	T__regoperator:     "_REGOPERATOR",
+	T__regclass:        "_REGCLASS",
+	T__regtype:         "_REGTYPE",
+	T_record:           "RECORD",
+	T_cstring:          "CSTRING",
+	T_any:              "ANY",
+	T_anyarray:         "ANYARRAY",
+	T_void:             "VOID",
+	T_trigger:          "TRIGGER",
+	T_language_handler: "LANGUAGE_HANDLER",
+	T_internal:         "INTERNAL",
+	T_opaque:           "OPAQUE",
+	T_anyelement:       "ANYELEMENT",
+	T__record:          "_RECORD",
+	T_anynonarray:      "ANYNONARRAY",
+	T_pg_authid:        "PG_AUTHID",
+	T_pg_auth_members:  "PG_AUTH_MEMBERS",
+	T__txid_snapshot:   "_TXID_SNAPSHOT",
+	T_uuid:             "UUID",
+	T__uuid:            "_UUID",
+	T_txid_snapshot:    "TXID_SNAPSHOT",
+	T_fdw_handler:      "FDW_HANDLER",
+	T_pg_lsn:           "PG_LSN",
+	T__pg_lsn:          "_PG_LSN",
+	T_tsm_handler:      "TSM_HANDLER",
+	T_anyenum:          "ANYENUM",
+	T_tsvector:         "TSVECTOR",
+	T_tsquery:          "TSQUERY",
+	T_gtsvector:        "GTSVECTOR",
+	T__tsvector:        "_TSVECTOR",
+	T__gtsvector:       "_GTSVECTOR",
+	T__tsquery:         "_TSQUERY",
+	T_regconfig:        "REGCONFIG",
+	T__regconfig:       "_REGCONFIG",
+	T_regdictionary:    "REGDICTIONARY",
+	T__regdictionary:   "_REGDICTIONARY",
+	T_jsonb:            "JSONB",
+	T__jsonb:           "_JSONB",
+	T_anyrange:         "ANYRANGE",
+	T_event_trigger:    "EVENT_TRIGGER",
+	T_int4range:        "INT4RANGE",
+	T__int4range:       "_INT4RANGE",
+	T_numrange:         "NUMRANGE",
+	T__numrange:        "_NUMRANGE",
+	T_tsrange:          "TSRANGE",
+	T__tsrange:         "_TSRANGE",
+	T_tstzrange:        "TSTZRANGE",
+	T__tstzrange:       "_TSTZRANGE",
+	T_daterange:        "DATERANGE",
+	T__daterange:       "_DATERANGE",
+	T_int8range:        "INT8RANGE",
+	T__int8range:       "_INT8RANGE",
+	T_pg_shseclabel:    "PG_SHSECLABEL",
+	T_regnamespace:     "REGNAMESPACE",
+	T__regnamespace:    "_REGNAMESPACE",
+	T_regrole:          "REGROLE",
+	T__regrole:         "_REGROLE",
+}

vendor/github.com/lib/pq/rows.go

@@ -0,0 +1,93 @@
+package pq
+
+import (
+	"math"
+	"reflect"
+	"time"
+
+	"github.com/lib/pq/oid"
+)
+
+const headerSize = 4
+
+type fieldDesc struct {
+	// The object ID of the data type.
+	OID oid.Oid
+	// The data type size (see pg_type.typlen).
+	// Note that negative values denote variable-width types.
+	Len int
+	// The type modifier (see pg_attribute.atttypmod).
+	// The meaning of the modifier is type-specific.
+	Mod int
+}
+
+func (fd fieldDesc) Type() reflect.Type {
+	switch fd.OID {
+	case oid.T_int8:
+		return reflect.TypeOf(int64(0))
+	case oid.T_int4:
+		return reflect.TypeOf(int32(0))
+	case oid.T_int2:
+		return reflect.TypeOf(int16(0))
+	case oid.T_varchar, oid.T_text:
+		return reflect.TypeOf("")
+	case oid.T_bool:
+		return reflect.TypeOf(false)
+	case oid.T_date, oid.T_time, oid.T_timetz, oid.T_timestamp, oid.T_timestamptz:
+		return reflect.TypeOf(time.Time{})
+	case oid.T_bytea:
+		return reflect.TypeOf([]byte(nil))
+	default:
+		return reflect.TypeOf(new(interface{})).Elem()
+	}
+}
+
+func (fd fieldDesc) Name() string {
+	return oid.TypeName[fd.OID]
+}
+
+func (fd fieldDesc) Length() (length int64, ok bool) {
+	switch fd.OID {
+	case oid.T_text, oid.T_bytea:
+		return math.MaxInt64, true
+	case oid.T_varchar, oid.T_bpchar:
+		return int64(fd.Mod - headerSize), true
+	default:
+		return 0, false
+	}
+}
+
+func (fd fieldDesc) PrecisionScale() (precision, scale int64, ok bool) {
+	switch fd.OID {
+	case oid.T_numeric, oid.T__numeric:
+		mod := fd.Mod - headerSize
+		precision = int64((mod >> 16) & 0xffff)
+		scale = int64(mod & 0xffff)
+		return precision, scale, true
+	default:
+		return 0, 0, false
+	}
+}
+
+// ColumnTypeScanType returns the value type that can be used to scan types into.
+func (rs *rows) ColumnTypeScanType(index int) reflect.Type {
+	return rs.colTyps[index].Type()
+}
+
+// ColumnTypeDatabaseTypeName return the database system type name.
+func (rs *rows) ColumnTypeDatabaseTypeName(index int) string {
+	return rs.colTyps[index].Name()
+}
+
+// ColumnTypeLength returns the length of the column type if the column is a
+// variable length type. If the column is not a variable length type ok
+// should return false.
+func (rs *rows) ColumnTypeLength(index int) (length int64, ok bool) {
+	return rs.colTyps[index].Length()
+}
+
+// ColumnTypePrecisionScale should return the precision and scale for decimal
+// types. If not applicable, ok should be false.
+func (rs *rows) ColumnTypePrecisionScale(index int) (precision, scale int64, ok bool) {
+	return rs.colTyps[index].PrecisionScale()
+}

vendor/github.com/lib/pq/scram/scram.go

@@ -0,0 +1,264 @@
+// Copyright (c) 2014 - Gustavo Niemeyer <gustavo@niemeyer.net>
+//
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+// 1. Redistributions of source code must retain the above copyright notice, this
+//    list of conditions and the following disclaimer.
+// 2. Redistributions in binary form must reproduce the above copyright notice,
+//    this list of conditions and the following disclaimer in the documentation
+//    and/or other materials provided with the distribution.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+// ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+// ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Package scram implements a SCRAM-{SHA-1,etc} client per RFC5802.
+//
+// http://tools.ietf.org/html/rfc5802
+//
+package scram
+
+import (
+	"bytes"
+	"crypto/hmac"
+	"crypto/rand"
+	"encoding/base64"
+	"fmt"
+	"hash"
+	"strconv"
+	"strings"
+)
+
+// Client implements a SCRAM-* client (SCRAM-SHA-1, SCRAM-SHA-256, etc).
+//
+// A Client may be used within a SASL conversation with logic resembling:
+//
+//    var in []byte
+//    var client = scram.NewClient(sha1.New, user, pass)
+//    for client.Step(in) {
+//            out := client.Out()
+//            // send out to server
+//            in := serverOut
+//    }
+//    if client.Err() != nil {
+//            // auth failed
+//    }
+//
+type Client struct {
+	newHash func() hash.Hash
+
+	user string
+	pass string
+	step int
+	out  bytes.Buffer
+	err  error
+
+	clientNonce []byte
+	serverNonce []byte
+	saltedPass  []byte
+	authMsg     bytes.Buffer
+}
+
+// NewClient returns a new SCRAM-* client with the provided hash algorithm.
+//
+// For SCRAM-SHA-256, for example, use:
+//
+//    client := scram.NewClient(sha256.New, user, pass)
+//
+func NewClient(newHash func() hash.Hash, user, pass string) *Client {
+	c := &Client{
+		newHash: newHash,
+		user:    user,
+		pass:    pass,
+	}
+	c.out.Grow(256)
+	c.authMsg.Grow(256)
+	return c
+}
+
+// Out returns the data to be sent to the server in the current step.
+func (c *Client) Out() []byte {
+	if c.out.Len() == 0 {
+		return nil
+	}
+	return c.out.Bytes()
+}
+
+// Err returns the error that occurred, or nil if there were no errors.
+func (c *Client) Err() error {
+	return c.err
+}
+
+// SetNonce sets the client nonce to the provided value.
+// If not set, the nonce is generated automatically out of crypto/rand on the first step.
+func (c *Client) SetNonce(nonce []byte) {
+	c.clientNonce = nonce
+}
+
+var escaper = strings.NewReplacer("=", "=3D", ",", "=2C")
+
+// Step processes the incoming data from the server and makes the
+// next round of data for the server available via Client.Out.
+// Step returns false if there are no errors and more data is
+// still expected.
+func (c *Client) Step(in []byte) bool {
+	c.out.Reset()
+	if c.step > 2 || c.err != nil {
+		return false
+	}
+	c.step++
+	switch c.step {
+	case 1:
+		c.err = c.step1(in)
+	case 2:
+		c.err = c.step2(in)
+	case 3:
+		c.err = c.step3(in)
+	}
+	return c.step > 2 || c.err != nil
+}
+
+func (c *Client) step1(in []byte) error {
+	if len(c.clientNonce) == 0 {
+		const nonceLen = 16
+		buf := make([]byte, nonceLen+b64.EncodedLen(nonceLen))
+		if _, err := rand.Read(buf[:nonceLen]); err != nil {
+			return fmt.Errorf("cannot read random SCRAM-SHA-256 nonce from operating system: %v", err)
+		}
+		c.clientNonce = buf[nonceLen:]
+		b64.Encode(c.clientNonce, buf[:nonceLen])
+	}
+	c.authMsg.WriteString("n=")
+	escaper.WriteString(&c.authMsg, c.user)
+	c.authMsg.WriteString(",r=")
+	c.authMsg.Write(c.clientNonce)
+
+	c.out.WriteString("n,,")
+	c.out.Write(c.authMsg.Bytes())
+	return nil
+}
+
+var b64 = base64.StdEncoding
+
+func (c *Client) step2(in []byte) error {
+	c.authMsg.WriteByte(',')
+	c.authMsg.Write(in)
+
+	fields := bytes.Split(in, []byte(","))
+	if len(fields) != 3 {
+		return fmt.Errorf("expected 3 fields in first SCRAM-SHA-256 server message, got %d: %q", len(fields), in)
+	}
+	if !bytes.HasPrefix(fields[0], []byte("r=")) || len(fields[0]) < 2 {
+		return fmt.Errorf("server sent an invalid SCRAM-SHA-256 nonce: %q", fields[0])
+	}
+	if !bytes.HasPrefix(fields[1], []byte("s=")) || len(fields[1]) < 6 {
+		return fmt.Errorf("server sent an invalid SCRAM-SHA-256 salt: %q", fields[1])
+	}
+	if !bytes.HasPrefix(fields[2], []byte("i=")) || len(fields[2]) < 6 {
+		return fmt.Errorf("server sent an invalid SCRAM-SHA-256 iteration count: %q", fields[2])
+	}
+
+	c.serverNonce = fields[0][2:]
+	if !bytes.HasPrefix(c.serverNonce, c.clientNonce) {
+		return fmt.Errorf("server SCRAM-SHA-256 nonce is not prefixed by client nonce: got %q, want %q+\"...\"", c.serverNonce, c.clientNonce)
+	}
+
+	salt := make([]byte, b64.DecodedLen(len(fields[1][2:])))
+	n, err := b64.Decode(salt, fields[1][2:])
+	if err != nil {
+		return fmt.Errorf("cannot decode SCRAM-SHA-256 salt sent by server: %q", fields[1])
+	}
+	salt = salt[:n]
+	iterCount, err := strconv.Atoi(string(fields[2][2:]))
+	if err != nil {
+		return fmt.Errorf("server sent an invalid SCRAM-SHA-256 iteration count: %q", fields[2])
+	}
+	c.saltPassword(salt, iterCount)
+
+	c.authMsg.WriteString(",c=biws,r=")
+	c.authMsg.Write(c.serverNonce)
+
+	c.out.WriteString("c=biws,r=")
+	c.out.Write(c.serverNonce)
+	c.out.WriteString(",p=")
+	c.out.Write(c.clientProof())
+	return nil
+}
+
+func (c *Client) step3(in []byte) error {
+	var isv, ise bool
+	var fields = bytes.Split(in, []byte(","))
+	if len(fields) == 1 {
+		isv = bytes.HasPrefix(fields[0], []byte("v="))
+		ise = bytes.HasPrefix(fields[0], []byte("e="))
+	}
+	if ise {
+		return fmt.Errorf("SCRAM-SHA-256 authentication error: %s", fields[0][2:])
+	} else if !isv {
+		return fmt.Errorf("unsupported SCRAM-SHA-256 final message from server: %q", in)
+	}
+	if !bytes.Equal(c.serverSignature(), fields[0][2:]) {
+		return fmt.Errorf("cannot authenticate SCRAM-SHA-256 server signature: %q", fields[0][2:])
+	}
+	return nil
+}
+
+func (c *Client) saltPassword(salt []byte, iterCount int) {
+	mac := hmac.New(c.newHash, []byte(c.pass))
+	mac.Write(salt)
+	mac.Write([]byte{0, 0, 0, 1})
+	ui := mac.Sum(nil)
+	hi := make([]byte, len(ui))
+	copy(hi, ui)
+	for i := 1; i < iterCount; i++ {
+		mac.Reset()
+		mac.Write(ui)
+		mac.Sum(ui[:0])
+		for j, b := range ui {
+			hi[j] ^= b
+		}
+	}
+	c.saltedPass = hi
+}
+
+func (c *Client) clientProof() []byte {
+	mac := hmac.New(c.newHash, c.saltedPass)
+	mac.Write([]byte("Client Key"))
+	clientKey := mac.Sum(nil)
+	hash := c.newHash()
+	hash.Write(clientKey)
+	storedKey := hash.Sum(nil)
+	mac = hmac.New(c.newHash, storedKey)
+	mac.Write(c.authMsg.Bytes())
+	clientProof := mac.Sum(nil)
+	for i, b := range clientKey {
+		clientProof[i] ^= b
+	}
+	clientProof64 := make([]byte, b64.EncodedLen(len(clientProof)))
+	b64.Encode(clientProof64, clientProof)
+	return clientProof64
+}
+
+func (c *Client) serverSignature() []byte {
+	mac := hmac.New(c.newHash, c.saltedPass)
+	mac.Write([]byte("Server Key"))
+	serverKey := mac.Sum(nil)
+
+	mac = hmac.New(c.newHash, serverKey)
+	mac.Write(c.authMsg.Bytes())
+	serverSignature := mac.Sum(nil)
+
+	encoded := make([]byte, b64.EncodedLen(len(serverSignature)))
+	b64.Encode(encoded, serverSignature)
+	return encoded
+}

vendor/github.com/lib/pq/ssl.go

@@ -0,0 +1,204 @@
+package pq
+
+import (
+	"crypto/tls"
+	"crypto/x509"
+	"io/ioutil"
+	"net"
+	"os"
+	"os/user"
+	"path/filepath"
+	"strings"
+)
+
+// ssl generates a function to upgrade a net.Conn based on the "sslmode" and
+// related settings. The function is nil when no upgrade should take place.
+func ssl(o values) (func(net.Conn) (net.Conn, error), error) {
+	verifyCaOnly := false
+	tlsConf := tls.Config{}
+	switch mode := o["sslmode"]; mode {
+	// "require" is the default.
+	case "", "require":
+		// We must skip TLS's own verification since it requires full
+		// verification since Go 1.3.
+		tlsConf.InsecureSkipVerify = true
+
+		// From http://www.postgresql.org/docs/current/static/libpq-ssl.html:
+		//
+		// Note: For backwards compatibility with earlier versions of
+		// PostgreSQL, if a root CA file exists, the behavior of
+		// sslmode=require will be the same as that of verify-ca, meaning the
+		// server certificate is validated against the CA. Relying on this
+		// behavior is discouraged, and applications that need certificate
+		// validation should always use verify-ca or verify-full.
+		if sslrootcert, ok := o["sslrootcert"]; ok {
+			if _, err := os.Stat(sslrootcert); err == nil {
+				verifyCaOnly = true
+			} else {
+				delete(o, "sslrootcert")
+			}
+		}
+	case "verify-ca":
+		// We must skip TLS's own verification since it requires full
+		// verification since Go 1.3.
+		tlsConf.InsecureSkipVerify = true
+		verifyCaOnly = true
+	case "verify-full":
+		tlsConf.ServerName = o["host"]
+	case "disable":
+		return nil, nil
+	default:
+		return nil, fmterrorf(`unsupported sslmode %q; only "require" (default), "verify-full", "verify-ca", and "disable" supported`, mode)
+	}
+
+	// Set Server Name Indication (SNI), if enabled by connection parameters.
+	// By default SNI is on, any value which is not starting with "1" disables
+	// SNI -- that is the same check vanilla libpq uses.
+	if sslsni := o["sslsni"]; sslsni == "" || strings.HasPrefix(sslsni, "1") {
+		// RFC 6066 asks to not set SNI if the host is a literal IP address (IPv4
+		// or IPv6). This check is coded already crypto.tls.hostnameInSNI, so
+		// just always set ServerName here and let crypto/tls do the filtering.
+		tlsConf.ServerName = o["host"]
+	}
+
+	err := sslClientCertificates(&tlsConf, o)
+	if err != nil {
+		return nil, err
+	}
+	err = sslCertificateAuthority(&tlsConf, o)
+	if err != nil {
+		return nil, err
+	}
+
+	// Accept renegotiation requests initiated by the backend.
+	//
+	// Renegotiation was deprecated then removed from PostgreSQL 9.5, but
+	// the default configuration of older versions has it enabled. Redshift
+	// also initiates renegotiations and cannot be reconfigured.
+	tlsConf.Renegotiation = tls.RenegotiateFreelyAsClient
+
+	return func(conn net.Conn) (net.Conn, error) {
+		client := tls.Client(conn, &tlsConf)
+		if verifyCaOnly {
+			err := sslVerifyCertificateAuthority(client, &tlsConf)
+			if err != nil {
+				return nil, err
+			}
+		}
+		return client, nil
+	}, nil
+}
+
+// sslClientCertificates adds the certificate specified in the "sslcert" and
+// "sslkey" settings, or if they aren't set, from the .postgresql directory
+// in the user's home directory. The configured files must exist and have
+// the correct permissions.
+func sslClientCertificates(tlsConf *tls.Config, o values) error {
+	sslinline := o["sslinline"]
+	if sslinline == "true" {
+		cert, err := tls.X509KeyPair([]byte(o["sslcert"]), []byte(o["sslkey"]))
+		if err != nil {
+			return err
+		}
+		tlsConf.Certificates = []tls.Certificate{cert}
+		return nil
+	}
+
+	// user.Current() might fail when cross-compiling. We have to ignore the
+	// error and continue without home directory defaults, since we wouldn't
+	// know from where to load them.
+	user, _ := user.Current()
+
+	// In libpq, the client certificate is only loaded if the setting is not blank.
+	//
+	// https://github.com/postgres/postgres/blob/REL9_6_2/src/interfaces/libpq/fe-secure-openssl.c#L1036-L1037
+	sslcert := o["sslcert"]
+	if len(sslcert) == 0 && user != nil {
+		sslcert = filepath.Join(user.HomeDir, ".postgresql", "postgresql.crt")
+	}
+	// https://github.com/postgres/postgres/blob/REL9_6_2/src/interfaces/libpq/fe-secure-openssl.c#L1045
+	if len(sslcert) == 0 {
+		return nil
+	}
+	// https://github.com/postgres/postgres/blob/REL9_6_2/src/interfaces/libpq/fe-secure-openssl.c#L1050:L1054
+	if _, err := os.Stat(sslcert); os.IsNotExist(err) {
+		return nil
+	} else if err != nil {
+		return err
+	}
+
+	// In libpq, the ssl key is only loaded if the setting is not blank.
+	//
+	// https://github.com/postgres/postgres/blob/REL9_6_2/src/interfaces/libpq/fe-secure-openssl.c#L1123-L1222
+	sslkey := o["sslkey"]
+	if len(sslkey) == 0 && user != nil {
+		sslkey = filepath.Join(user.HomeDir, ".postgresql", "postgresql.key")
+	}
+
+	if len(sslkey) > 0 {
+		if err := sslKeyPermissions(sslkey); err != nil {
+			return err
+		}
+	}
+
+	cert, err := tls.LoadX509KeyPair(sslcert, sslkey)
+	if err != nil {
+		return err
+	}
+
+	tlsConf.Certificates = []tls.Certificate{cert}
+	return nil
+}
+
+// sslCertificateAuthority adds the RootCA specified in the "sslrootcert" setting.
+func sslCertificateAuthority(tlsConf *tls.Config, o values) error {
+	// In libpq, the root certificate is only loaded if the setting is not blank.
+	//
+	// https://github.com/postgres/postgres/blob/REL9_6_2/src/interfaces/libpq/fe-secure-openssl.c#L950-L951
+	if sslrootcert := o["sslrootcert"]; len(sslrootcert) > 0 {
+		tlsConf.RootCAs = x509.NewCertPool()
+
+		sslinline := o["sslinline"]
+
+		var cert []byte
+		if sslinline == "true" {
+			cert = []byte(sslrootcert)
+		} else {
+			var err error
+			cert, err = ioutil.ReadFile(sslrootcert)
+			if err != nil {
+				return err
+			}
+		}
+
+		if !tlsConf.RootCAs.AppendCertsFromPEM(cert) {
+			return fmterrorf("couldn't parse pem in sslrootcert")
+		}
+	}
+
+	return nil
+}
+
+// sslVerifyCertificateAuthority carries out a TLS handshake to the server and
+// verifies the presented certificate against the CA, i.e. the one specified in
+// sslrootcert or the system CA if sslrootcert was not specified.
+func sslVerifyCertificateAuthority(client *tls.Conn, tlsConf *tls.Config) error {
+	err := client.Handshake()
+	if err != nil {
+		return err
+	}
+	certs := client.ConnectionState().PeerCertificates
+	opts := x509.VerifyOptions{
+		DNSName:       client.ConnectionState().ServerName,
+		Intermediates: x509.NewCertPool(),
+		Roots:         tlsConf.RootCAs,
+	}
+	for i, cert := range certs {
+		if i == 0 {
+			continue
+		}
+		opts.Intermediates.AddCert(cert)
+	}
+	_, err = certs[0].Verify(opts)
+	return err
+}

vendor/github.com/lib/pq/ssl_permissions.go

@@ -0,0 +1,93 @@
+//go:build !windows
+// +build !windows
+
+package pq
+
+import (
+	"errors"
+	"os"
+	"syscall"
+)
+
+const (
+	rootUserID = uint32(0)
+
+	// The maximum permissions that a private key file owned by a regular user
+	// is allowed to have. This translates to u=rw.
+	maxUserOwnedKeyPermissions os.FileMode = 0600
+
+	// The maximum permissions that a private key file owned by root is allowed
+	// to have. This translates to u=rw,g=r.
+	maxRootOwnedKeyPermissions os.FileMode = 0640
+)
+
+var (
+	errSSLKeyHasUnacceptableUserPermissions = errors.New("permissions for files not owned by root should be u=rw (0600) or less")
+	errSSLKeyHasUnacceptableRootPermissions = errors.New("permissions for root owned files should be u=rw,g=r (0640) or less")
+)
+
+// sslKeyPermissions checks the permissions on user-supplied ssl key files.
+// The key file should have very little access.
+//
+// libpq does not check key file permissions on Windows.
+func sslKeyPermissions(sslkey string) error {
+	info, err := os.Stat(sslkey)
+	if err != nil {
+		return err
+	}
+
+	err = hasCorrectPermissions(info)
+
+	// return ErrSSLKeyHasWorldPermissions for backwards compatability with
+	// existing code.
+	if err == errSSLKeyHasUnacceptableUserPermissions || err == errSSLKeyHasUnacceptableRootPermissions {
+		err = ErrSSLKeyHasWorldPermissions
+	}
+	return err
+}
+
+// hasCorrectPermissions checks the file info (and the unix-specific stat_t
+// output) to verify that the permissions on the file are correct.
+//
+// If the file is owned by the same user the process is running as,
+// the file should only have 0600 (u=rw). If the file is owned by root,
+// and the group matches the group that the process is running in, the
+// permissions cannot be more than 0640 (u=rw,g=r). The file should
+// never have world permissions.
+//
+// Returns an error when the permission check fails.
+func hasCorrectPermissions(info os.FileInfo) error {
+	// if file's permission matches 0600, allow access.
+	userPermissionMask := (os.FileMode(0777) ^ maxUserOwnedKeyPermissions)
+
+	// regardless of if we're running as root or not, 0600 is acceptable,
+	// so we return if we match the regular user permission mask.
+	if info.Mode().Perm()&userPermissionMask == 0 {
+		return nil
+	}
+
+	// We need to pull the Unix file information to get the file's owner.
+	// If we can't access it, there's some sort of operating system level error
+	// and we should fail rather than attempting to use faulty information.
+	sysInfo := info.Sys()
+	if sysInfo == nil {
+		return ErrSSLKeyUnknownOwnership
+	}
+
+	unixStat, ok := sysInfo.(*syscall.Stat_t)
+	if !ok {
+		return ErrSSLKeyUnknownOwnership
+	}
+
+	// if the file is owned by root, we allow 0640 (u=rw,g=r) to match what
+	// Postgres does.
+	if unixStat.Uid == rootUserID {
+		rootPermissionMask := (os.FileMode(0777) ^ maxRootOwnedKeyPermissions)
+		if info.Mode().Perm()&rootPermissionMask != 0 {
+			return errSSLKeyHasUnacceptableRootPermissions
+		}
+		return nil
+	}
+
+	return errSSLKeyHasUnacceptableUserPermissions
+}

vendor/github.com/lib/pq/ssl_windows.go

@@ -0,0 +1,10 @@
+//go:build windows
+// +build windows
+
+package pq
+
+// sslKeyPermissions checks the permissions on user-supplied ssl key files.
+// The key file should have very little access.
+//
+// libpq does not check key file permissions on Windows.
+func sslKeyPermissions(string) error { return nil }

vendor/github.com/lib/pq/url.go

@@ -0,0 +1,76 @@
+package pq
+
+import (
+	"fmt"
+	"net"
+	nurl "net/url"
+	"sort"
+	"strings"
+)
+
+// ParseURL no longer needs to be used by clients of this library since supplying a URL as a
+// connection string to sql.Open() is now supported:
+//
+//	sql.Open("postgres", "postgres://bob:secret@1.2.3.4:5432/mydb?sslmode=verify-full")
+//
+// It remains exported here for backwards-compatibility.
+//
+// ParseURL converts a url to a connection string for driver.Open.
+// Example:
+//
+//	"postgres://bob:secret@1.2.3.4:5432/mydb?sslmode=verify-full"
+//
+// converts to:
+//
+//	"user=bob password=secret host=1.2.3.4 port=5432 dbname=mydb sslmode=verify-full"
+//
+// A minimal example:
+//
+//	"postgres://"
+//
+// This will be blank, causing driver.Open to use all of the defaults
+func ParseURL(url string) (string, error) {
+	u, err := nurl.Parse(url)
+	if err != nil {
+		return "", err
+	}
+
+	if u.Scheme != "postgres" && u.Scheme != "postgresql" {
+		return "", fmt.Errorf("invalid connection protocol: %s", u.Scheme)
+	}
+
+	var kvs []string
+	escaper := strings.NewReplacer(`'`, `\'`, `\`, `\\`)
+	accrue := func(k, v string) {
+		if v != "" {
+			kvs = append(kvs, k+"='"+escaper.Replace(v)+"'")
+		}
+	}
+
+	if u.User != nil {
+		v := u.User.Username()
+		accrue("user", v)
+
+		v, _ = u.User.Password()
+		accrue("password", v)
+	}
+
+	if host, port, err := net.SplitHostPort(u.Host); err != nil {
+		accrue("host", u.Host)
+	} else {
+		accrue("host", host)
+		accrue("port", port)
+	}
+
+	if u.Path != "" {
+		accrue("dbname", u.Path[1:])
+	}
+
+	q := u.Query()
+	for k := range q {
+		accrue(k, q.Get(k))
+	}
+
+	sort.Strings(kvs) // Makes testing easier (not a performance concern)
+	return strings.Join(kvs, " "), nil
+}

vendor/github.com/lib/pq/user_other.go

@@ -0,0 +1,10 @@
+// Package pq is a pure Go Postgres driver for the database/sql package.
+
+//go:build js || android || hurd || zos
+// +build js android hurd zos
+
+package pq
+
+func userCurrent() (string, error) {
+	return "", ErrCouldNotDetectUsername
+}

vendor/github.com/lib/pq/user_posix.go

@@ -0,0 +1,25 @@
+// Package pq is a pure Go Postgres driver for the database/sql package.
+
+//go:build aix || darwin || dragonfly || freebsd || (linux && !android) || nacl || netbsd || openbsd || plan9 || solaris || rumprun || illumos
+// +build aix darwin dragonfly freebsd linux,!android nacl netbsd openbsd plan9 solaris rumprun illumos
+
+package pq
+
+import (
+	"os"
+	"os/user"
+)
+
+func userCurrent() (string, error) {
+	u, err := user.Current()
+	if err == nil {
+		return u.Username, nil
+	}
+
+	name := os.Getenv("USER")
+	if name != "" {
+		return name, nil
+	}
+
+	return "", ErrCouldNotDetectUsername
+}

vendor/github.com/lib/pq/user_windows.go

@@ -0,0 +1,27 @@
+// Package pq is a pure Go Postgres driver for the database/sql package.
+package pq
+
+import (
+	"path/filepath"
+	"syscall"
+)
+
+// Perform Windows user name lookup identically to libpq.
+//
+// The PostgreSQL code makes use of the legacy Win32 function
+// GetUserName, and that function has not been imported into stock Go.
+// GetUserNameEx is available though, the difference being that a
+// wider range of names are available.  To get the output to be the
+// same as GetUserName, only the base (or last) component of the
+// result is returned.
+func userCurrent() (string, error) {
+	pw_name := make([]uint16, 128)
+	pwname_size := uint32(len(pw_name)) - 1
+	err := syscall.GetUserNameEx(syscall.NameSamCompatible, &pw_name[0], &pwname_size)
+	if err != nil {
+		return "", ErrCouldNotDetectUsername
+	}
+	s := syscall.UTF16ToString(pw_name)
+	u := filepath.Base(s)
+	return u, nil
+}

vendor/github.com/lib/pq/uuid.go

@@ -0,0 +1,23 @@
+package pq
+
+import (
+	"encoding/hex"
+	"fmt"
+)
+
+// decodeUUIDBinary interprets the binary format of a uuid, returning it in text format.
+func decodeUUIDBinary(src []byte) ([]byte, error) {
+	if len(src) != 16 {
+		return nil, fmt.Errorf("pq: unable to decode uuid; bad length: %d", len(src))
+	}
+
+	dst := make([]byte, 36)
+	dst[8], dst[13], dst[18], dst[23] = '-', '-', '-', '-'
+	hex.Encode(dst[0:], src[0:4])
+	hex.Encode(dst[9:], src[4:6])
+	hex.Encode(dst[14:], src[6:8])
+	hex.Encode(dst[19:], src[8:10])
+	hex.Encode(dst[24:], src[10:16])
+
+	return dst, nil
+}

vendor/modules.txt

@@ -0,0 +1,14 @@
+# github.com/felixge/httpsnoop v1.0.3
+## explicit; go 1.13
+github.com/felixge/httpsnoop
+# github.com/gorilla/handlers v1.5.2
+## explicit; go 1.20
+github.com/gorilla/handlers
+# github.com/gorilla/mux v1.8.1
+## explicit; go 1.20
+github.com/gorilla/mux
+# github.com/lib/pq v1.10.9
+## explicit; go 1.13
+github.com/lib/pq
+github.com/lib/pq/oid
+github.com/lib/pq/scram