# Gin Web Framework
  
  <img align="right" width="159px" src="https://raw.githubusercontent.com/gin-gonic/logo/master/color.png">
  
  [![Build Status](https://travis-ci.org/gin-gonic/gin.svg)](https://travis-ci.org/gin-gonic/gin)
  [![codecov](https://codecov.io/gh/gin-gonic/gin/branch/master/graph/badge.svg)](https://codecov.io/gh/gin-gonic/gin)
  [![Go Report Card](https://goreportcard.com/badge/github.com/gin-gonic/gin)](https://goreportcard.com/report/github.com/gin-gonic/gin)
  [![GoDoc](https://godoc.org/github.com/gin-gonic/gin?status.svg)](https://godoc.org/github.com/gin-gonic/gin)
  [![Join the chat at https://gitter.im/gin-gonic/gin](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/gin-gonic/gin?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
  [![Sourcegraph](https://sourcegraph.com/github.com/gin-gonic/gin/-/badge.svg)](https://sourcegraph.com/github.com/gin-gonic/gin?badge)
  [![Open Source Helpers](https://www.codetriage.com/gin-gonic/gin/badges/users.svg)](https://www.codetriage.com/gin-gonic/gin)
  [![Release](https://img.shields.io/github/release/gin-gonic/gin.svg?style=flat-square)](https://github.com/gin-gonic/gin/releases)
  
  Gin is a web framework written in Go (Golang). It features a martini-like API with much better performance, up to 40 times faster thanks to [httprouter](https://github.com/julienschmidt/httprouter). If you need performance and good productivity, you will love Gin.
  
  
  ## Contents
  
  - [Installation](#installation)
  - [Prerequisite](#prerequisite)
  - [Quick start](#quick-start)
  - [Benchmarks](#benchmarks)
  - [Gin v1.stable](#gin-v1-stable)
  - [Build with jsoniter](#build-with-jsoniter)
  - [API Examples](#api-examples)
      - [Using GET,POST,PUT,PATCH,DELETE and OPTIONS](#using-get-post-put-patch-delete-and-options)
      - [Parameters in path](#parameters-in-path)
      - [Querystring parameters](#querystring-parameters)
      - [Multipart/Urlencoded Form](#multiparturlencoded-form)
      - [Another example: query + post form](#another-example-query--post-form)
      - [Map as querystring or postform parameters](#map-as-querystring-or-postform-parameters)
      - [Upload files](#upload-files)
      - [Grouping routes](#grouping-routes)
      - [Blank Gin without middleware by default](#blank-gin-without-middleware-by-default)
      - [Using middleware](#using-middleware)
      - [How to write log file](#how-to-write-log-file)
      - [Custom Log Format](#custom-log-format)
      - [Model binding and validation](#model-binding-and-validation)
      - [Custom Validators](#custom-validators)
      - [Only Bind Query String](#only-bind-query-string)
      - [Bind Query String or Post Data](#bind-query-string-or-post-data)
      - [Bind Uri](#bind-uri)
      - [Bind HTML checkboxes](#bind-html-checkboxes)
      - [Multipart/Urlencoded binding](#multiparturlencoded-binding)
      - [XML, JSON, YAML and ProtoBuf rendering](#xml-json-yaml-and-protobuf-rendering)
      - [JSONP rendering](#jsonp)
      - [Serving static files](#serving-static-files)
      - [Serving data from reader](#serving-data-from-reader)
      - [HTML rendering](#html-rendering)
      - [Multitemplate](#multitemplate)
      - [Redirects](#redirects)
      - [Custom Middleware](#custom-middleware)
      - [Using BasicAuth() middleware](#using-basicauth-middleware)
      - [Goroutines inside a middleware](#goroutines-inside-a-middleware)
      - [Custom HTTP configuration](#custom-http-configuration)
      - [Support Let's Encrypt](#support-lets-encrypt)
      - [Run multiple service using Gin](#run-multiple-service-using-gin)
      - [Graceful restart or stop](#graceful-restart-or-stop)
      - [Build a single binary with templates](#build-a-single-binary-with-templates)
      - [Bind form-data request with custom struct](#bind-form-data-request-with-custom-struct)
      - [Try to bind body into different structs](#try-to-bind-body-into-different-structs)
      - [http2 server push](#http2-server-push)
      - [Define format for the log of routes](#define-format-for-the-log-of-routes)
      - [Set and get a cookie](#set-and-get-a-cookie)
  - [Testing](#testing)
  - [Users](#users)
  
  ## Installation
  
  To install Gin package, you need to install Go and set your Go workspace first.
  
  1. The first need [Go](https://golang.org/) installed (**version 1.8+ is required**), then you can use the below Go command to install Gin.
  
  ```sh
  $ go get -u github.com/gin-gonic/gin
  ```
  
  2. Import it in your code:
  
  ```go
  import "github.com/gin-gonic/gin"
  ```
  
  3. (Optional) Import `net/http`. This is required for example if using constants such as `http.StatusOK`.
  
  ```go
  import "net/http"
  ```
  
  ### Use a vendor tool like [Govendor](https://github.com/kardianos/govendor)
  
  1. `go get` govendor
  
  ```sh
  $ go get github.com/kardianos/govendor
  ```
  2. Create your project folder and `cd` inside
  
  ```sh
  $ mkdir -p $GOPATH/src/github.com/myusername/project && cd "$_"
  ```
  
  3. Vendor init your project and add gin
  
  ```sh
  $ govendor init
  $ govendor fetch github.com/gin-gonic/gin@v1.3
  ```
  
  4. Copy a starting template inside your project
  
  ```sh
  $ curl https://raw.githubusercontent.com/gin-gonic/examples/master/basic/main.go > main.go
  ```
  
  5. Run your project
  
  ```sh
  $ go run main.go
  ```
  
  ## Prerequisite
  
  Now Gin requires Go 1.6 or later and Go 1.7 will be required soon.
  
  ## Quick start
   
  ```sh
  # assume the following codes in example.go file
  $ cat example.go
  ```
  
  ```go
  package main
  
  import "github.com/gin-gonic/gin"
  
  func main() {
  	r := gin.Default()
  	r.GET("/ping", func(c *gin.Context) {
  		c.JSON(200, gin.H{
  			"message": "pong",
  		})
  	})
  	r.Run() // listen and serve on 0.0.0.0:8080
  }
  ```
  
  ```
  # run example.go and visit 0.0.0.0:8080/ping on browser
  $ go run example.go
  ```
  
  ## Benchmarks
  
  Gin uses a custom version of [HttpRouter](https://github.com/julienschmidt/httprouter)
  
  [See all benchmarks](/BENCHMARKS.md)
  
  Benchmark name                              | (1)        | (2)         | (3) 		    | (4)
  --------------------------------------------|-----------:|------------:|-----------:|---------:
  **BenchmarkGin_GithubAll**                  | **30000**  |  **48375**  |     **0**  |   **0**
  BenchmarkAce_GithubAll                      |   10000    |   134059    |   13792    |   167
  BenchmarkBear_GithubAll                     |    5000    |   534445    |   86448    |   943
  BenchmarkBeego_GithubAll                    |    3000    |   592444    |   74705    |   812
  BenchmarkBone_GithubAll                     |     200    |  6957308    |  698784    |  8453
  BenchmarkDenco_GithubAll                    |   10000    |   158819    |   20224    |   167
  BenchmarkEcho_GithubAll                     |   10000    |   154700    |    6496    |   203
  BenchmarkGocraftWeb_GithubAll               |    3000    |   570806    |  131656    |  1686
  BenchmarkGoji_GithubAll                     |    2000    |   818034    |   56112    |   334
  BenchmarkGojiv2_GithubAll                   |    2000    |  1213973    |  274768    |  3712
  BenchmarkGoJsonRest_GithubAll               |    2000    |   785796    |  134371    |  2737
  BenchmarkGoRestful_GithubAll                |     300    |  5238188    |  689672    |  4519
  BenchmarkGorillaMux_GithubAll               |     100    | 10257726    |  211840    |  2272
  BenchmarkHttpRouter_GithubAll               |   20000    |   105414    |   13792    |   167
  BenchmarkHttpTreeMux_GithubAll              |   10000    |   319934    |   65856    |   671
  BenchmarkKocha_GithubAll                    |   10000    |   209442    |   23304    |   843
  BenchmarkLARS_GithubAll                     |   20000    |    62565    |       0    |     0
  BenchmarkMacaron_GithubAll                  |    2000    |  1161270    |  204194    |  2000
  BenchmarkMartini_GithubAll                  |     200    |  9991713    |  226549    |  2325
  BenchmarkPat_GithubAll                      |     200    |  5590793    | 1499568    | 27435
  BenchmarkPossum_GithubAll                   |   10000    |   319768    |   84448    |   609
  BenchmarkR2router_GithubAll                 |   10000    |   305134    |   77328    |   979
  BenchmarkRivet_GithubAll                    |   10000    |   132134    |   16272    |   167
  BenchmarkTango_GithubAll                    |    3000    |   552754    |   63826    |  1618
  BenchmarkTigerTonic_GithubAll               |    1000    |  1439483    |  239104    |  5374
  BenchmarkTraffic_GithubAll                  |     100    | 11383067    | 2659329    | 21848
  BenchmarkVulcan_GithubAll                   |    5000    |   394253    |   19894    |   609
  
  - (1): Total Repetitions achieved in constant time, higher means more confident result
  - (2): Single Repetition Duration (ns/op), lower is better
  - (3): Heap Memory (B/op), lower is better
  - (4): Average Allocations per Repetition (allocs/op), lower is better
  
  ## Gin v1. stable
  
  - [x] Zero allocation router.
  - [x] Still the fastest http router and framework. From routing to writing.
  - [x] Complete suite of unit tests
  - [x] Battle tested
  - [x] API frozen, new releases will not break your code.
  
  ## Build with [jsoniter](https://github.com/json-iterator/go)
  
  Gin uses `encoding/json` as default json package but you can change to [jsoniter](https://github.com/json-iterator/go) by build from other tags.
  
  ```sh
  $ go build -tags=jsoniter .
  ```
  
  ## API Examples
  
  You can find a number of ready-to-run examples at [Gin examples repository](https://github.com/gin-gonic/examples).
  
  ### Using GET, POST, PUT, PATCH, DELETE and OPTIONS
  
  ```go
  func main() {
  	// Creates a gin router with default middleware:
  	// logger and recovery (crash-free) middleware
  	router := gin.Default()
  
  	router.GET("/someGet", getting)
  	router.POST("/somePost", posting)
  	router.PUT("/somePut", putting)
  	router.DELETE("/someDelete", deleting)
  	router.PATCH("/somePatch", patching)
  	router.HEAD("/someHead", head)
  	router.OPTIONS("/someOptions", options)
  
  	// By default it serves on :8080 unless a
  	// PORT environment variable was defined.
  	router.Run()
  	// router.Run(":3000") for a hard coded port
  }
  ```
  
  ### Parameters in path
  
  ```go
  func main() {
  	router := gin.Default()
  
  	// This handler will match /user/john but will not match /user/ or /user
  	router.GET("/user/:name", func(c *gin.Context) {
  		name := c.Param("name")
  		c.String(http.StatusOK, "Hello %s", name)
  	})
  
  	// However, this one will match /user/john/ and also /user/john/send
  	// If no other routers match /user/john, it will redirect to /user/john/
  	router.GET("/user/:name/*action", func(c *gin.Context) {
  		name := c.Param("name")
  		action := c.Param("action")
  		message := name + " is " + action
  		c.String(http.StatusOK, message)
  	})
  
  	router.Run(":8080")
  }
  ```
  
  ### Querystring parameters
  
  ```go
  func main() {
  	router := gin.Default()
  
  	// Query string parameters are parsed using the existing underlying request object.
  	// The request responds to a url matching:  /welcome?firstname=Jane&lastname=Doe
  	router.GET("/welcome", func(c *gin.Context) {
  		firstname := c.DefaultQuery("firstname", "Guest")
  		lastname := c.Query("lastname") // shortcut for c.Request.URL.Query().Get("lastname")
  
  		c.String(http.StatusOK, "Hello %s %s", firstname, lastname)
  	})
  	router.Run(":8080")
  }
  ```
  
  ### Multipart/Urlencoded Form
  
  ```go
  func main() {
  	router := gin.Default()
  
  	router.POST("/form_post", func(c *gin.Context) {
  		message := c.PostForm("message")
  		nick := c.DefaultPostForm("nick", "anonymous")
  
  		c.JSON(200, gin.H{
  			"status":  "posted",
  			"message": message,
  			"nick":    nick,
  		})
  	})
  	router.Run(":8080")
  }
  ```
  
  ### Another example: query + post form
  
  ```
  POST /post?id=1234&page=1 HTTP/1.1
  Content-Type: application/x-www-form-urlencoded
  
  name=manu&message=this_is_great
  ```
  
  ```go
  func main() {
  	router := gin.Default()
  
  	router.POST("/post", func(c *gin.Context) {
  
  		id := c.Query("id")
  		page := c.DefaultQuery("page", "0")
  		name := c.PostForm("name")
  		message := c.PostForm("message")
  
  		fmt.Printf("id: %s; page: %s; name: %s; message: %s", id, page, name, message)
  	})
  	router.Run(":8080")
  }
  ```
  
  ```
  id: 1234; page: 1; name: manu; message: this_is_great
  ```
  
  ### Map as querystring or postform parameters
  
  ```
  POST /post?ids[a]=1234&ids[b]=hello HTTP/1.1
  Content-Type: application/x-www-form-urlencoded
  
  names[first]=thinkerou&names[second]=tianou
  ```
  
  ```go
  func main() {
  	router := gin.Default()
  
  	router.POST("/post", func(c *gin.Context) {
  
  		ids := c.QueryMap("ids")
  		names := c.PostFormMap("names")
  
  		fmt.Printf("ids: %v; names: %v", ids, names)
  	})
  	router.Run(":8080")
  }
  ```
  
  ```
  ids: map[b:hello a:1234], names: map[second:tianou first:thinkerou]
  ```
  
  ### Upload files
  
  #### Single file
  
  References issue [#774](https://github.com/gin-gonic/gin/issues/774) and detail [example code](https://github.com/gin-gonic/examples/tree/master/upload-file/single).
  
  `file.Filename` **SHOULD NOT** be trusted. See [`Content-Disposition` on MDN](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Disposition#Directives) and [#1693](https://github.com/gin-gonic/gin/issues/1693)
  
  > The filename is always optional and must not be used blindly by the application: path information should be stripped, and conversion to the server file system rules should be done.
  
  ```go
  func main() {
  	router := gin.Default()
  	// Set a lower memory limit for multipart forms (default is 32 MiB)
  	// router.MaxMultipartMemory = 8 << 20  // 8 MiB
  	router.POST("/upload", func(c *gin.Context) {
  		// single file
  		file, _ := c.FormFile("file")
  		log.Println(file.Filename)
  
  		// Upload the file to specific dst.
  		// c.SaveUploadedFile(file, dst)
  
  		c.String(http.StatusOK, fmt.Sprintf("'%s' uploaded!", file.Filename))
  	})
  	router.Run(":8080")
  }
  ```
  
  How to `curl`:
  
  ```bash
  curl -X POST http://localhost:8080/upload \
    -F "file=@/Users/appleboy/test.zip" \
    -H "Content-Type: multipart/form-data"
  ```
  
  #### Multiple files
  
  See the detail [example code](https://github.com/gin-gonic/examples/tree/master/upload-file/multiple).
  
  ```go
  func main() {
  	router := gin.Default()
  	// Set a lower memory limit for multipart forms (default is 32 MiB)
  	// router.MaxMultipartMemory = 8 << 20  // 8 MiB
  	router.POST("/upload", func(c *gin.Context) {
  		// Multipart form
  		form, _ := c.MultipartForm()
  		files := form.File["upload[]"]
  
  		for _, file := range files {
  			log.Println(file.Filename)
  
  			// Upload the file to specific dst.
  			// c.SaveUploadedFile(file, dst)
  		}
  		c.String(http.StatusOK, fmt.Sprintf("%d files uploaded!", len(files)))
  	})
  	router.Run(":8080")
  }
  ```
  
  How to `curl`:
  
  ```bash
  curl -X POST http://localhost:8080/upload \
    -F "upload[]=@/Users/appleboy/test1.zip" \
    -F "upload[]=@/Users/appleboy/test2.zip" \
    -H "Content-Type: multipart/form-data"
  ```
  
  ### Grouping routes
  
  ```go
  func main() {
  	router := gin.Default()
  
  	// Simple group: v1
  	v1 := router.Group("/v1")
  	{
  		v1.POST("/login", loginEndpoint)
  		v1.POST("/submit", submitEndpoint)
  		v1.POST("/read", readEndpoint)
  	}
  
  	// Simple group: v2
  	v2 := router.Group("/v2")
  	{
  		v2.POST("/login", loginEndpoint)
  		v2.POST("/submit", submitEndpoint)
  		v2.POST("/read", readEndpoint)
  	}
  
  	router.Run(":8080")
  }
  ```
  
  ### Blank Gin without middleware by default
  
  Use
  
  ```go
  r := gin.New()
  ```
  
  instead of
  
  ```go
  // Default With the Logger and Recovery middleware already attached
  r := gin.Default()
  ```
  
  
  ### Using middleware
  ```go
  func main() {
  	// Creates a router without any middleware by default
  	r := gin.New()
  
  	// Global middleware
  	// Logger middleware will write the logs to gin.DefaultWriter even if you set with GIN_MODE=release.
  	// By default gin.DefaultWriter = os.Stdout
  	r.Use(gin.Logger())
  
  	// Recovery middleware recovers from any panics and writes a 500 if there was one.
  	r.Use(gin.Recovery())
  
  	// Per route middleware, you can add as many as you desire.
  	r.GET("/benchmark", MyBenchLogger(), benchEndpoint)
  
  	// Authorization group
  	// authorized := r.Group("/", AuthRequired())
  	// exactly the same as:
  	authorized := r.Group("/")
  	// per group middleware! in this case we use the custom created
  	// AuthRequired() middleware just in the "authorized" group.
  	authorized.Use(AuthRequired())
  	{
  		authorized.POST("/login", loginEndpoint)
  		authorized.POST("/submit", submitEndpoint)
  		authorized.POST("/read", readEndpoint)
  
  		// nested group
  		testing := authorized.Group("testing")
  		testing.GET("/analytics", analyticsEndpoint)
  	}
  
  	// Listen and serve on 0.0.0.0:8080
  	r.Run(":8080")
  }
  ```
  
  ### How to write log file
  ```go
  func main() {
      // Disable Console Color, you don't need console color when writing the logs to file.
      gin.DisableConsoleColor()
  
      // Logging to a file.
      f, _ := os.Create("gin.log")
      gin.DefaultWriter = io.MultiWriter(f)
  
      // Use the following code if you need to write the logs to file and console at the same time.
      // gin.DefaultWriter = io.MultiWriter(f, os.Stdout)
  
      router := gin.Default()
      router.GET("/ping", func(c *gin.Context) {
          c.String(200, "pong")
      })
  
      router.Run(":8080")
  }
  ```
  
  ### Custom Log Format
  ```go
  func main() {
  	router := gin.New()
  
  	// LoggerWithFormatter middleware will write the logs to gin.DefaultWriter
  	// By default gin.DefaultWriter = os.Stdout
  	router.Use(gin.LoggerWithFormatter(func(param gin.LogFormatterParams) string {
  
  		// your custom format
  		return fmt.Sprintf("%s - [%s] \"%s %s %s %d %s \"%s\" %s\"
  ",
  				param.ClientIP,
  				param.TimeStamp.Format(time.RFC1123),
  				param.Method,
  				param.Path,
  				param.Request.Proto,
  				param.StatusCode,
  				param.Latency,
  				param.Request.UserAgent(),
  				param.ErrorMessage,
  		)
  	}))
  	router.Use(gin.Recovery())
  
  	router.GET("/ping", func(c *gin.Context) {
  		c.String(200, "pong")
  	})
  
  	router.Run(":8080")
  }
  ```
  
  **Sample Output**
  ```
  ::1 - [Fri, 07 Dec 2018 17:04:38 JST] "GET /ping HTTP/1.1 200 122.767µs "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/71.0.3578.80 Safari/537.36" "
  ```
  
  ### Controlling Log output coloring 
  
  By default, logs output on console should be colorized depending on the detected TTY.
  
  Never colorize logs: 
  
  ```go
  func main() {
      // Disable log's color
      gin.DisableConsoleColor()
      
      // Creates a gin router with default middleware:
      // logger and recovery (crash-free) middleware
      router := gin.Default()
      
      router.GET("/ping", func(c *gin.Context) {
          c.String(200, "pong")
      })
      
      router.Run(":8080")
  }
  ```
  
  Always colorize logs: 
  
  ```go
  func main() {
      // Force log's color
      gin.ForceConsoleColor()
      
      // Creates a gin router with default middleware:
      // logger and recovery (crash-free) middleware
      router := gin.Default()
      
      router.GET("/ping", func(c *gin.Context) {
          c.String(200, "pong")
      })
      
      router.Run(":8080")
  }
  ```
  
  ### Model binding and validation
  
  To bind a request body into a type, use model binding. We currently support binding of JSON, XML, YAML and standard form values (foo=bar&boo=baz).
  
  Gin uses [**go-playground/validator.v8**](https://github.com/go-playground/validator) for validation. Check the full docs on tags usage [here](http://godoc.org/gopkg.in/go-playground/validator.v8#hdr-Baked_In_Validators_and_Tags).
  
  Note that you need to set the corresponding binding tag on all fields you want to bind. For example, when binding from JSON, set `json:"fieldname"`.
  
  Also, Gin provides two sets of methods for binding:
  - **Type** - Must bind
    - **Methods** - `Bind`, `BindJSON`, `BindXML`, `BindQuery`, `BindYAML`
    - **Behavior** - These methods use `MustBindWith` under the hood. If there is a binding error, the request is aborted with `c.AbortWithError(400, err).SetType(ErrorTypeBind)`. This sets the response status code to 400 and the `Content-Type` header is set to `text/plain; charset=utf-8`. Note that if you try to set the response code after this, it will result in a warning `[GIN-debug] [WARNING] Headers were already written. Wanted to override status code 400 with 422`. If you wish to have greater control over the behavior, consider using the `ShouldBind` equivalent method.
  - **Type** - Should bind
    - **Methods** - `ShouldBind`, `ShouldBindJSON`, `ShouldBindXML`, `ShouldBindQuery`, `ShouldBindYAML`
    - **Behavior** - These methods use `ShouldBindWith` under the hood. If there is a binding error, the error is returned and it is the developer's responsibility to handle the request and error appropriately.
  
  When using the Bind-method, Gin tries to infer the binder depending on the Content-Type header. If you are sure what you are binding, you can use `MustBindWith` or `ShouldBindWith`.
  
  You can also specify that specific fields are required. If a field is decorated with `binding:"required"` and has a empty value when binding, an error will be returned.
  
  ```go
  // Binding from JSON
  type Login struct {
  	User     string `form:"user" json:"user" xml:"user"  binding:"required"`
  	Password string `form:"password" json:"password" xml:"password" binding:"required"`
  }
  
  func main() {
  	router := gin.Default()
  
  	// Example for binding JSON ({"user": "manu", "password": "123"})
  	router.POST("/loginJSON", func(c *gin.Context) {
  		var json Login
  		if err := c.ShouldBindJSON(&json); err != nil {
  			c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
  			return
  		}
  		
  		if json.User != "manu" || json.Password != "123" {
  			c.JSON(http.StatusUnauthorized, gin.H{"status": "unauthorized"})
  			return
  		} 
  		
  		c.JSON(http.StatusOK, gin.H{"status": "you are logged in"})
  	})
  
  	// Example for binding XML (
  	//	<?xml version="1.0" encoding="UTF-8"?>
  	//	<root>
  	//		<user>user</user>
  	//		<password>123</password>
  	//	</root>)
  	router.POST("/loginXML", func(c *gin.Context) {
  		var xml Login
  		if err := c.ShouldBindXML(&xml); err != nil {
  			c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
  			return
  		}
  		
  		if xml.User != "manu" || xml.Password != "123" {
  			c.JSON(http.StatusUnauthorized, gin.H{"status": "unauthorized"})
  			return
  		} 
  		
  		c.JSON(http.StatusOK, gin.H{"status": "you are logged in"})
  	})
  
  	// Example for binding a HTML form (user=manu&password=123)
  	router.POST("/loginForm", func(c *gin.Context) {
  		var form Login
  		// This will infer what binder to use depending on the content-type header.
  		if err := c.ShouldBind(&form); err != nil {
  			c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
  			return
  		}
  		
  		if form.User != "manu" || form.Password != "123" {
  			c.JSON(http.StatusUnauthorized, gin.H{"status": "unauthorized"})
  			return
  		} 
  		
  		c.JSON(http.StatusOK, gin.H{"status": "you are logged in"})
  	})
  
  	// Listen and serve on 0.0.0.0:8080
  	router.Run(":8080")
  }
  ```
  
  **Sample request**
  ```shell
  $ curl -v -X POST \
    http://localhost:8080/loginJSON \
    -H 'content-type: application/json' \
    -d '{ "user": "manu" }'
  > POST /loginJSON HTTP/1.1
  > Host: localhost:8080
  > User-Agent: curl/7.51.0
  > Accept: */*
  > content-type: application/json
  > Content-Length: 18
  >
  * upload completely sent off: 18 out of 18 bytes
  < HTTP/1.1 400 Bad Request
  < Content-Type: application/json; charset=utf-8
  < Date: Fri, 04 Aug 2017 03:51:31 GMT
  < Content-Length: 100
  <
  {"error":"Key: 'Login.Password' Error:Field validation for 'Password' failed on the 'required' tag"}
  ```
  
  **Skip validate**
  
  When running the above example using the above the `curl` command, it returns error. Because the example use `binding:"required"` for `Password`. If use `binding:"-"` for `Password`, then it will not return error when running the above example again.
  
  ### Custom Validators
  
  It is also possible to register custom validators. See the [example code](https://github.com/gin-gonic/examples/tree/master/custom-validation/server.go).
  
  ```go
  package main
  
  import (
  	"net/http"
  	"reflect"
  	"time"
  
  	"github.com/gin-gonic/gin"
  	"github.com/gin-gonic/gin/binding"
  	"gopkg.in/go-playground/validator.v8"
  )
  
  // Booking contains binded and validated data.
  type Booking struct {
  	CheckIn  time.Time `form:"check_in" binding:"required,bookabledate" time_format:"2006-01-02"`
  	CheckOut time.Time `form:"check_out" binding:"required,gtfield=CheckIn" time_format:"2006-01-02"`
  }
  
  func bookableDate(
  	v *validator.Validate, topStruct reflect.Value, currentStructOrField reflect.Value,
  	field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string,
  ) bool {
  	if date, ok := field.Interface().(time.Time); ok {
  		today := time.Now()
  		if today.Year() > date.Year() || today.YearDay() > date.YearDay() {
  			return false
  		}
  	}
  	return true
  }
  
  func main() {
  	route := gin.Default()
  
  	if v, ok := binding.Validator.Engine().(*validator.Validate); ok {
  		v.RegisterValidation("bookabledate", bookableDate)
  	}
  
  	route.GET("/bookable", getBookable)
  	route.Run(":8085")
  }
  
  func getBookable(c *gin.Context) {
  	var b Booking
  	if err := c.ShouldBindWith(&b, binding.Query); err == nil {
  		c.JSON(http.StatusOK, gin.H{"message": "Booking dates are valid!"})
  	} else {
  		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
  	}
  }
  ```
  
  ```console
  $ curl "localhost:8085/bookable?check_in=2018-04-16&check_out=2018-04-17"
  {"message":"Booking dates are valid!"}
  
  $ curl "localhost:8085/bookable?check_in=2018-03-08&check_out=2018-03-09"
  {"error":"Key: 'Booking.CheckIn' Error:Field validation for 'CheckIn' failed on the 'bookabledate' tag"}
  ```
  
  [Struct level validations](https://github.com/go-playground/validator/releases/tag/v8.7) can also be registered this way.
  See the [struct-lvl-validation example](https://github.com/gin-gonic/examples/tree/master/struct-lvl-validations) to learn more.
  
  ### Only Bind Query String
  
  `ShouldBindQuery` function only binds the query params and not the post data. See the [detail information](https://github.com/gin-gonic/gin/issues/742#issuecomment-315953017).
  
  ```go
  package main
  
  import (
  	"log"
  
  	"github.com/gin-gonic/gin"
  )
  
  type Person struct {
  	Name    string `form:"name"`
  	Address string `form:"address"`
  }
  
  func main() {
  	route := gin.Default()
  	route.Any("/testing", startPage)
  	route.Run(":8085")
  }
  
  func startPage(c *gin.Context) {
  	var person Person
  	if c.ShouldBindQuery(&person) == nil {
  		log.Println("====== Only Bind By Query String ======")
  		log.Println(person.Name)
  		log.Println(person.Address)
  	}
  	c.String(200, "Success")
  }
  
  ```
  
  ### Bind Query String or Post Data
  
  See the [detail information](https://github.com/gin-gonic/gin/issues/742#issuecomment-264681292).
  
  ```go
  package main
  
  import (
  	"log"
  	"time"
  
  	"github.com/gin-gonic/gin"
  )
  
  type Person struct {
  	Name     string    `form:"name"`
  	Address  string    `form:"address"`
  	Birthday time.Time `form:"birthday" time_format:"2006-01-02" time_utc:"1"`
  }
  
  func main() {
  	route := gin.Default()
  	route.GET("/testing", startPage)
  	route.Run(":8085")
  }
  
  func startPage(c *gin.Context) {
  	var person Person
  	// If `GET`, only `Form` binding engine (`query`) used.
  	// If `POST`, first checks the `content-type` for `JSON` or `XML`, then uses `Form` (`form-data`).
  	// See more at https://github.com/gin-gonic/gin/blob/master/binding/binding.go#L48
  	if c.ShouldBind(&person) == nil {
  		log.Println(person.Name)
  		log.Println(person.Address)
  		log.Println(person.Birthday)
  	}
  
  	c.String(200, "Success")
  }
  ```
  
  Test it with:
  ```sh
  $ curl -X GET "localhost:8085/testing?name=appleboy&address=xyz&birthday=1992-03-15"
  ```
  
  ### Bind Uri
  
  See the [detail information](https://github.com/gin-gonic/gin/issues/846).
  
  ```go
  package main
  
  import "github.com/gin-gonic/gin"
  
  type Person struct {
  	ID string `uri:"id" binding:"required,uuid"`
  	Name string `uri:"name" binding:"required"`
  }
  
  func main() {
  	route := gin.Default()
  	route.GET("/:name/:id", func(c *gin.Context) {
  		var person Person
  		if err := c.ShouldBindUri(&person); err != nil {
  			c.JSON(400, gin.H{"msg": err})
  			return
  		}
  		c.JSON(200, gin.H{"name": person.Name, "uuid": person.ID})
  	})
  	route.Run(":8088")
  }
  ```
  
  Test it with:
  ```sh
  $ curl -v localhost:8088/thinkerou/987fbc97-4bed-5078-9f07-9141ba07c9f3
  $ curl -v localhost:8088/thinkerou/not-uuid
  ```
  
  ### Bind HTML checkboxes
  
  See the [detail information](https://github.com/gin-gonic/gin/issues/129#issuecomment-124260092)
  
  main.go
  
  ```go
  ...
  
  type myForm struct {
      Colors []string `form:"colors[]"`
  }
  
  ...
  
  func formHandler(c *gin.Context) {
      var fakeForm myForm
      c.ShouldBind(&fakeForm)
      c.JSON(200, gin.H{"color": fakeForm.Colors})
  }
  
  ...
  
  ```
  
  form.html
  
  ```html
  <form action="/" method="POST">
      <p>Check some colors</p>
      <label for="red">Red</label>
      <input type="checkbox" name="colors[]" value="red" id="red">
      <label for="green">Green</label>
      <input type="checkbox" name="colors[]" value="green" id="green">
      <label for="blue">Blue</label>
      <input type="checkbox" name="colors[]" value="blue" id="blue">
      <input type="submit">
  </form>
  ```
  
  result:
  
  ```
  {"color":["red","green","blue"]}
  ```
  
  ### Multipart/Urlencoded binding
  
  ```go
  package main
  
  import (
  	"github.com/gin-gonic/gin"
  )
  
  type LoginForm struct {
  	User     string `form:"user" binding:"required"`
  	Password string `form:"password" binding:"required"`
  }
  
  func main() {
  	router := gin.Default()
  	router.POST("/login", func(c *gin.Context) {
  		// you can bind multipart form with explicit binding declaration:
  		// c.ShouldBindWith(&form, binding.Form)
  		// or you can simply use autobinding with ShouldBind method:
  		var form LoginForm
  		// in this case proper binding will be automatically selected
  		if c.ShouldBind(&form) == nil {
  			if form.User == "user" && form.Password == "password" {
  				c.JSON(200, gin.H{"status": "you are logged in"})
  			} else {
  				c.JSON(401, gin.H{"status": "unauthorized"})
  			}
  		}
  	})
  	router.Run(":8080")
  }
  ```
  
  Test it with:
  ```sh
  $ curl -v --form user=user --form password=password http://localhost:8080/login
  ```
  
  ### XML, JSON, YAML and ProtoBuf rendering
  
  ```go
  func main() {
  	r := gin.Default()
  
  	// gin.H is a shortcut for map[string]interface{}
  	r.GET("/someJSON", func(c *gin.Context) {
  		c.JSON(http.StatusOK, gin.H{"message": "hey", "status": http.StatusOK})
  	})
  
  	r.GET("/moreJSON", func(c *gin.Context) {
  		// You also can use a struct
  		var msg struct {
  			Name    string `json:"user"`
  			Message string
  			Number  int
  		}
  		msg.Name = "Lena"
  		msg.Message = "hey"
  		msg.Number = 123
  		// Note that msg.Name becomes "user" in the JSON
  		// Will output  :   {"user": "Lena", "Message": "hey", "Number": 123}
  		c.JSON(http.StatusOK, msg)
  	})
  
  	r.GET("/someXML", func(c *gin.Context) {
  		c.XML(http.StatusOK, gin.H{"message": "hey", "status": http.StatusOK})
  	})
  
  	r.GET("/someYAML", func(c *gin.Context) {
  		c.YAML(http.StatusOK, gin.H{"message": "hey", "status": http.StatusOK})
  	})
  
  	r.GET("/someProtoBuf", func(c *gin.Context) {
  		reps := []int64{int64(1), int64(2)}
  		label := "test"
  		// The specific definition of protobuf is written in the testdata/protoexample file.
  		data := &protoexample.Test{
  			Label: &label,
  			Reps:  reps,
  		}
  		// Note that data becomes binary data in the response
  		// Will output protoexample.Test protobuf serialized data
  		c.ProtoBuf(http.StatusOK, data)
  	})
  
  	// Listen and serve on 0.0.0.0:8080
  	r.Run(":8080")
  }
  ```
  
  #### SecureJSON
  
  Using SecureJSON to prevent json hijacking. Default prepends `"while(1),"` to response body if the given struct is array values.
  
  ```go
  func main() {
  	r := gin.Default()
  
  	// You can also use your own secure json prefix
  	// r.SecureJsonPrefix(")]}',
  ")
  
  	r.GET("/someJSON", func(c *gin.Context) {
  		names := []string{"lena", "austin", "foo"}
  
  		// Will output  :   while(1);["lena","austin","foo"]
  		c.SecureJSON(http.StatusOK, names)
  	})
  
  	// Listen and serve on 0.0.0.0:8080
  	r.Run(":8080")
  }
  ```
  #### JSONP
  
  Using JSONP to request data from a server  in a different domain. Add callback to response body if the query parameter callback exists.
  
  ```go
  func main() {
  	r := gin.Default()
  
  	r.GET("/JSONP?callback=x", func(c *gin.Context) {
  		data := map[string]interface{}{
  			"foo": "bar",
  		}
  		
  		//callback is x
  		// Will output  :   x({\"foo\":\"bar\"})
  		c.JSONP(http.StatusOK, data)
  	})
  
  	// Listen and serve on 0.0.0.0:8080
  	r.Run(":8080")
  }
  ```
  
  #### AsciiJSON
  
  Using AsciiJSON to Generates ASCII-only JSON with escaped non-ASCII chracters.
  
  ```go
  func main() {
  	r := gin.Default()
  
  	r.GET("/someJSON", func(c *gin.Context) {
  		data := map[string]interface{}{
  			"lang": "GO语言",
  			"tag":  "<br>",
  		}
  
  		// will output : {"lang":"GO\u8bed\u8a00","tag":"\u003cbr\u003e"}
  		c.AsciiJSON(http.StatusOK, data)
  	})
  
  	// Listen and serve on 0.0.0.0:8080
  	r.Run(":8080")
  }
  ```
  
  #### PureJSON
  
  Normally, JSON replaces special HTML characters with their unicode entities, e.g. `<` becomes  `\u003c`. If you want to encode such characters literally, you can use PureJSON instead.
  This feature is unavailable in Go 1.6 and lower.
  
  ```go
  func main() {
  	r := gin.Default()
  	
  	// Serves unicode entities
  	r.GET("/json", func(c *gin.Context) {
  		c.JSON(200, gin.H{
  			"html": "<b>Hello, world!</b>",
  		})
  	})
  	
  	// Serves literal characters
  	r.GET("/purejson", func(c *gin.Context) {
  		c.PureJSON(200, gin.H{
  			"html": "<b>Hello, world!</b>",
  		})
  	})
  	
  	// listen and serve on 0.0.0.0:8080
  	r.Run(":8080")
  }
  ```
  
  ### Serving static files
  
  ```go
  func main() {
  	router := gin.Default()
  	router.Static("/assets", "./assets")
  	router.StaticFS("/more_static", http.Dir("my_file_system"))
  	router.StaticFile("/favicon.ico", "./resources/favicon.ico")
  
  	// Listen and serve on 0.0.0.0:8080
  	router.Run(":8080")
  }
  ```
  
  ### Serving data from reader
  
  ```go
  func main() {
  	router := gin.Default()
  	router.GET("/someDataFromReader", func(c *gin.Context) {
  		response, err := http.Get("https://raw.githubusercontent.com/gin-gonic/logo/master/color.png")
  		if err != nil || response.StatusCode != http.StatusOK {
  			c.Status(http.StatusServiceUnavailable)
  			return
  		}
  
  		reader := response.Body
  		contentLength := response.ContentLength
  		contentType := response.Header.Get("Content-Type")
  
  		extraHeaders := map[string]string{
  			"Content-Disposition": `attachment; filename="gopher.png"`,
  		}
  
  		c.DataFromReader(http.StatusOK, contentLength, contentType, reader, extraHeaders)
  	})
  	router.Run(":8080")
  }
  ```
  
  ### HTML rendering
  
  Using LoadHTMLGlob() or LoadHTMLFiles()
  
  ```go
  func main() {
  	router := gin.Default()
  	router.LoadHTMLGlob("templates/*")
  	//router.LoadHTMLFiles("templates/template1.html", "templates/template2.html")
  	router.GET("/index", func(c *gin.Context) {
  		c.HTML(http.StatusOK, "index.tmpl", gin.H{
  			"title": "Main website",
  		})
  	})
  	router.Run(":8080")
  }
  ```
  
  templates/index.tmpl
  
  ```html
  <html>
  	<h1>
  		{{ .title }}
  	</h1>
  </html>
  ```
  
  Using templates with same name in different directories
  
  ```go
  func main() {
  	router := gin.Default()
  	router.LoadHTMLGlob("templates/**/*")
  	router.GET("/posts/index", func(c *gin.Context) {
  		c.HTML(http.StatusOK, "posts/index.tmpl", gin.H{
  			"title": "Posts",
  		})
  	})
  	router.GET("/users/index", func(c *gin.Context) {
  		c.HTML(http.StatusOK, "users/index.tmpl", gin.H{
  			"title": "Users",
  		})
  	})
  	router.Run(":8080")
  }
  ```
  
  templates/posts/index.tmpl
  
  ```html
  {{ define "posts/index.tmpl" }}
  <html><h1>
  	{{ .title }}
  </h1>
  <p>Using posts/index.tmpl</p>
  </html>
  {{ end }}
  ```
  
  templates/users/index.tmpl
  
  ```html
  {{ define "users/index.tmpl" }}
  <html><h1>
  	{{ .title }}
  </h1>
  <p>Using users/index.tmpl</p>
  </html>
  {{ end }}
  ```
  
  #### Custom Template renderer
  
  You can also use your own html template render
  
  ```go
  import "html/template"
  
  func main() {
  	router := gin.Default()
  	html := template.Must(template.ParseFiles("file1", "file2"))
  	router.SetHTMLTemplate(html)
  	router.Run(":8080")
  }
  ```
  
  #### Custom Delimiters
  
  You may use custom delims
  
  ```go
  	r := gin.Default()
  	r.Delims("{[{", "}]}")
  	r.LoadHTMLGlob("/path/to/templates")
  ```
  
  #### Custom Template Funcs
  
  See the detail [example code](https://github.com/gin-gonic/examples/tree/master/template).
  
  main.go
  
  ```go
  import (
      "fmt"
      "html/template"
      "net/http"
      "time"
  
      "github.com/gin-gonic/gin"
  )
  
  func formatAsDate(t time.Time) string {
      year, month, day := t.Date()
      return fmt.Sprintf("%d%02d/%02d", year, month, day)
  }
  
  func main() {
      router := gin.Default()
      router.Delims("{[{", "}]}")
      router.SetFuncMap(template.FuncMap{
          "formatAsDate": formatAsDate,
      })
      router.LoadHTMLFiles("./testdata/template/raw.tmpl")
  
      router.GET("/raw", func(c *gin.Context) {
          c.HTML(http.StatusOK, "raw.tmpl", map[string]interface{}{
              "now": time.Date(2017, 07, 01, 0, 0, 0, 0, time.UTC),
          })
      })
  
      router.Run(":8080")
  }
  
  ```
  
  raw.tmpl
  
  ```html
  Date: {[{.now | formatAsDate}]}
  ```
  
  Result:
  ```
  Date: 2017/07/01
  ```
  
  ### Multitemplate
  
  Gin allow by default use only one html.Template. Check [a multitemplate render](https://github.com/gin-contrib/multitemplate) for using features like go 1.6 `block template`.
  
  ### Redirects
  
  Issuing a HTTP redirect is easy. Both internal and external locations are supported.
  
  ```go
  r.GET("/test", func(c *gin.Context) {
  	c.Redirect(http.StatusMovedPermanently, "http://www.google.com/")
  })
  ```
  
  
  Issuing a Router redirect, use `HandleContext` like below.
  
  ``` go
  r.GET("/test", func(c *gin.Context) {
      c.Request.URL.Path = "/test2"
      r.HandleContext(c)
  })
  r.GET("/test2", func(c *gin.Context) {
      c.JSON(200, gin.H{"hello": "world"})
  })
  ```
  
  
  ### Custom Middleware
  
  ```go
  func Logger() gin.HandlerFunc {
  	return func(c *gin.Context) {
  		t := time.Now()
  
  		// Set example variable
  		c.Set("example", "12345")
  
  		// before request
  
  		c.Next()
  
  		// after request
  		latency := time.Since(t)
  		log.Print(latency)
  
  		// access the status we are sending
  		status := c.Writer.Status()
  		log.Println(status)
  	}
  }
  
  func main() {
  	r := gin.New()
  	r.Use(Logger())
  
  	r.GET("/test", func(c *gin.Context) {
  		example := c.MustGet("example").(string)
  
  		// it would print: "12345"
  		log.Println(example)
  	})
  
  	// Listen and serve on 0.0.0.0:8080
  	r.Run(":8080")
  }
  ```
  
  ### Using BasicAuth() middleware
  
  ```go
  // simulate some private data
  var secrets = gin.H{
  	"foo":    gin.H{"email": "foo@bar.com", "phone": "123433"},
  	"austin": gin.H{"email": "austin@example.com", "phone": "666"},
  	"lena":   gin.H{"email": "lena@guapa.com", "phone": "523443"},
  }
  
  func main() {
  	r := gin.Default()
  
  	// Group using gin.BasicAuth() middleware
  	// gin.Accounts is a shortcut for map[string]string
  	authorized := r.Group("/admin", gin.BasicAuth(gin.Accounts{
  		"foo":    "bar",
  		"austin": "1234",
  		"lena":   "hello2",
  		"manu":   "4321",
  	}))
  
  	// /admin/secrets endpoint
  	// hit "localhost:8080/admin/secrets
  	authorized.GET("/secrets", func(c *gin.Context) {
  		// get user, it was set by the BasicAuth middleware
  		user := c.MustGet(gin.AuthUserKey).(string)
  		if secret, ok := secrets[user]; ok {
  			c.JSON(http.StatusOK, gin.H{"user": user, "secret": secret})
  		} else {
  			c.JSON(http.StatusOK, gin.H{"user": user, "secret": "NO SECRET :("})
  		}
  	})
  
  	// Listen and serve on 0.0.0.0:8080
  	r.Run(":8080")
  }
  ```
  
  ### Goroutines inside a middleware
  
  When starting new Goroutines inside a middleware or handler, you **SHOULD NOT** use the original context inside it, you have to use a read-only copy.
  
  ```go
  func main() {
  	r := gin.Default()
  
  	r.GET("/long_async", func(c *gin.Context) {
  		// create copy to be used inside the goroutine
  		cCp := c.Copy()
  		go func() {
  			// simulate a long task with time.Sleep(). 5 seconds
  			time.Sleep(5 * time.Second)
  
  			// note that you are using the copied context "cCp", IMPORTANT
  			log.Println("Done! in path " + cCp.Request.URL.Path)
  		}()
  	})
  
  	r.GET("/long_sync", func(c *gin.Context) {
  		// simulate a long task with time.Sleep(). 5 seconds
  		time.Sleep(5 * time.Second)
  
  		// since we are NOT using a goroutine, we do not have to copy the context
  		log.Println("Done! in path " + c.Request.URL.Path)
  	})
  
  	// Listen and serve on 0.0.0.0:8080
  	r.Run(":8080")
  }
  ```
  
  ### Custom HTTP configuration
  
  Use `http.ListenAndServe()` directly, like this:
  
  ```go
  func main() {
  	router := gin.Default()
  	http.ListenAndServe(":8080", router)
  }
  ```
  or
  
  ```go
  func main() {
  	router := gin.Default()
  
  	s := &http.Server{
  		Addr:           ":8080",
  		Handler:        router,
  		ReadTimeout:    10 * time.Second,
  		WriteTimeout:   10 * time.Second,
  		MaxHeaderBytes: 1 << 20,
  	}
  	s.ListenAndServe()
  }
  ```
  
  ### Support Let's Encrypt
  
  example for 1-line LetsEncrypt HTTPS servers.
  
  ```go
  package main
  
  import (
  	"log"
  
  	"github.com/gin-gonic/autotls"
  	"github.com/gin-gonic/gin"
  )
  
  func main() {
  	r := gin.Default()
  
  	// Ping handler
  	r.GET("/ping", func(c *gin.Context) {
  		c.String(200, "pong")
  	})
  
  	log.Fatal(autotls.Run(r, "example1.com", "example2.com"))
  }
  ```
  
  example for custom autocert manager.
  
  ```go
  package main
  
  import (
  	"log"
  
  	"github.com/gin-gonic/autotls"
  	"github.com/gin-gonic/gin"
  	"golang.org/x/crypto/acme/autocert"
  )
  
  func main() {
  	r := gin.Default()
  
  	// Ping handler
  	r.GET("/ping", func(c *gin.Context) {
  		c.String(200, "pong")
  	})
  
  	m := autocert.Manager{
  		Prompt:     autocert.AcceptTOS,
  		HostPolicy: autocert.HostWhitelist("example1.com", "example2.com"),
  		Cache:      autocert.DirCache("/var/www/.cache"),
  	}
  
  	log.Fatal(autotls.RunWithManager(r, &m))
  }
  ```
  
  ### Run multiple service using Gin
  
  See the [question](https://github.com/gin-gonic/gin/issues/346) and try the following example:
  
  ```go
  package main
  
  import (
  	"log"
  	"net/http"
  	"time"
  
  	"github.com/gin-gonic/gin"
  	"golang.org/x/sync/errgroup"
  )
  
  var (
  	g errgroup.Group
  )
  
  func router01() http.Handler {
  	e := gin.New()
  	e.Use(gin.Recovery())
  	e.GET("/", func(c *gin.Context) {
  		c.JSON(
  			http.StatusOK,
  			gin.H{
  				"code":  http.StatusOK,
  				"error": "Welcome server 01",
  			},
  		)
  	})
  
  	return e
  }
  
  func router02() http.Handler {
  	e := gin.New()
  	e.Use(gin.Recovery())
  	e.GET("/", func(c *gin.Context) {
  		c.JSON(
  			http.StatusOK,
  			gin.H{
  				"code":  http.StatusOK,
  				"error": "Welcome server 02",
  			},
  		)
  	})
  
  	return e
  }
  
  func main() {
  	server01 := &http.Server{
  		Addr:         ":8080",
  		Handler:      router01(),
  		ReadTimeout:  5 * time.Second,
  		WriteTimeout: 10 * time.Second,
  	}
  
  	server02 := &http.Server{
  		Addr:         ":8081",
  		Handler:      router02(),
  		ReadTimeout:  5 * time.Second,
  		WriteTimeout: 10 * time.Second,
  	}
  
  	g.Go(func() error {
  		return server01.ListenAndServe()
  	})
  
  	g.Go(func() error {
  		return server02.ListenAndServe()
  	})
  
  	if err := g.Wait(); err != nil {
  		log.Fatal(err)
  	}
  }
  ```
  
  ### Graceful restart or stop
  
  Do you want to graceful restart or stop your web server?
  There are some ways this can be done.
  
  We can use [fvbock/endless](https://github.com/fvbock/endless) to replace the default `ListenAndServe`. Refer issue [#296](https://github.com/gin-gonic/gin/issues/296) for more details.
  
  ```go
  router := gin.Default()
  router.GET("/", handler)
  // [...]
  endless.ListenAndServe(":4242", router)
  ```
  
  An alternative to endless:
  
  * [manners](https://github.com/braintree/manners): A polite Go HTTP server that shuts down gracefully.
  * [graceful](https://github.com/tylerb/graceful): Graceful is a Go package enabling graceful shutdown of an http.Handler server.
  * [grace](https://github.com/facebookgo/grace): Graceful restart & zero downtime deploy for Go servers.
  
  If you are using Go 1.8, you may not need to use this library! Consider using http.Server's built-in [Shutdown()](https://golang.org/pkg/net/http/#Server.Shutdown) method for graceful shutdowns. See the full [graceful-shutdown](https://github.com/gin-gonic/examples/tree/master/graceful-shutdown) example with gin.
  
  ```go
  // +build go1.8
  
  package main
  
  import (
  	"context"
  	"log"
  	"net/http"
  	"os"
  	"os/signal"
  	"syscall"
  	"time"
  
  	"github.com/gin-gonic/gin"
  )
  
  func main() {
  	router := gin.Default()
  	router.GET("/", func(c *gin.Context) {
  		time.Sleep(5 * time.Second)
  		c.String(http.StatusOK, "Welcome Gin Server")
  	})
  
  	srv := &http.Server{
  		Addr:    ":8080",
  		Handler: router,
  	}
  
  	go func() {
  		// service connections
  		if err := srv.ListenAndServe(); err != nil && err != http.ErrServerClosed {
  			log.Fatalf("listen: %s
  ", err)
  		}
  	}()
  
  	// Wait for interrupt signal to gracefully shutdown the server with
  	// a timeout of 5 seconds.
  	quit := make(chan os.Signal)
  	// kill (no param) default send syscall.SIGTERM
  	// kill -2 is syscall.SIGINT
  	// kill -9 is syscall.SIGKILL but can"t be catch, so don't need add it
  	signal.Notify(quit, syscall.SIGINT, syscall.SIGTERM)
  	<-quit
  	log.Println("Shutdown Server ...")
  
  	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
  	defer cancel()
  	if err := srv.Shutdown(ctx); err != nil {
  		log.Fatal("Server Shutdown:", err)
  	}
  	// catching ctx.Done(). timeout of 5 seconds.
  	select {
  	case <-ctx.Done():
  		log.Println("timeout of 5 seconds.")
  	}
  	log.Println("Server exiting")
  }
  ```
  
  ### Build a single binary with templates
  
  You can build a server into a single binary containing templates by using [go-assets][].
  
  [go-assets]: https://github.com/jessevdk/go-assets
  
  ```go
  func main() {
  	r := gin.New()
  
  	t, err := loadTemplate()
  	if err != nil {
  		panic(err)
  	}
  	r.SetHTMLTemplate(t)
  
  	r.GET("/", func(c *gin.Context) {
  		c.HTML(http.StatusOK, "/html/index.tmpl",nil)
  	})
  	r.Run(":8080")
  }
  
  // loadTemplate loads templates embedded by go-assets-builder
  func loadTemplate() (*template.Template, error) {
  	t := template.New("")
  	for name, file := range Assets.Files {
  		if file.IsDir() || !strings.HasSuffix(name, ".tmpl") {
  			continue
  		}
  		h, err := ioutil.ReadAll(file)
  		if err != nil {
  			return nil, err
  		}
  		t, err = t.New(name).Parse(string(h))
  		if err != nil {
  			return nil, err
  		}
  	}
  	return t, nil
  }
  ```
  
  See a complete example in the `https://github.com/gin-gonic/examples/tree/master/assets-in-binary` directory.
  
  ### Bind form-data request with custom struct
  
  The follow example using custom struct:
  
  ```go
  type StructA struct {
      FieldA string `form:"field_a"`
  }
  
  type StructB struct {
      NestedStruct StructA
      FieldB string `form:"field_b"`
  }
  
  type StructC struct {
      NestedStructPointer *StructA
      FieldC string `form:"field_c"`
  }
  
  type StructD struct {
      NestedAnonyStruct struct {
          FieldX string `form:"field_x"`
      }
      FieldD string `form:"field_d"`
  }
  
  func GetDataB(c *gin.Context) {
      var b StructB
      c.Bind(&b)
      c.JSON(200, gin.H{
          "a": b.NestedStruct,
          "b": b.FieldB,
      })
  }
  
  func GetDataC(c *gin.Context) {
      var b StructC
      c.Bind(&b)
      c.JSON(200, gin.H{
          "a": b.NestedStructPointer,
          "c": b.FieldC,
      })
  }
  
  func GetDataD(c *gin.Context) {
      var b StructD
      c.Bind(&b)
      c.JSON(200, gin.H{
          "x": b.NestedAnonyStruct,
          "d": b.FieldD,
      })
  }
  
  func main() {
      r := gin.Default()
      r.GET("/getb", GetDataB)
      r.GET("/getc", GetDataC)
      r.GET("/getd", GetDataD)
  
      r.Run()
  }
  ```
  
  Using the command `curl` command result:
  
  ```
  $ curl "http://localhost:8080/getb?field_a=hello&field_b=world"
  {"a":{"FieldA":"hello"},"b":"world"}
  $ curl "http://localhost:8080/getc?field_a=hello&field_c=world"
  {"a":{"FieldA":"hello"},"c":"world"}
  $ curl "http://localhost:8080/getd?field_x=hello&field_d=world"
  {"d":"world","x":{"FieldX":"hello"}}
  ```
  
  ### Try to bind body into different structs
  
  The normal methods for binding request body consumes `c.Request.Body` and they
  cannot be called multiple times.
  
  ```go
  type formA struct {
    Foo string `json:"foo" xml:"foo" binding:"required"`
  }
  
  type formB struct {
    Bar string `json:"bar" xml:"bar" binding:"required"`
  }
  
  func SomeHandler(c *gin.Context) {
    objA := formA{}
    objB := formB{}
    // This c.ShouldBind consumes c.Request.Body and it cannot be reused.
    if errA := c.ShouldBind(&objA); errA == nil {
      c.String(http.StatusOK, `the body should be formA`)
    // Always an error is occurred by this because c.Request.Body is EOF now.
    } else if errB := c.ShouldBind(&objB); errB == nil {
      c.String(http.StatusOK, `the body should be formB`)
    } else {
      ...
    }
  }
  ```
  
  For this, you can use `c.ShouldBindBodyWith`.
  
  ```go
  func SomeHandler(c *gin.Context) {
    objA := formA{}
    objB := formB{}
    // This reads c.Request.Body and stores the result into the context.
    if errA := c.ShouldBindBodyWith(&objA, binding.JSON); errA == nil {
      c.String(http.StatusOK, `the body should be formA`)
    // At this time, it reuses body stored in the context.
    } else if errB := c.ShouldBindBodyWith(&objB, binding.JSON); errB == nil {
      c.String(http.StatusOK, `the body should be formB JSON`)
    // And it can accepts other formats
    } else if errB2 := c.ShouldBindBodyWith(&objB, binding.XML); errB2 == nil {
      c.String(http.StatusOK, `the body should be formB XML`)
    } else {
      ...
    }
  }
  ```
  
  * `c.ShouldBindBodyWith` stores body into the context before binding. This has
  a slight impact to performance, so you should not use this method if you are
  enough to call binding at once.
  * This feature is only needed for some formats -- `JSON`, `XML`, `MsgPack`,
  `ProtoBuf`. For other formats, `Query`, `Form`, `FormPost`, `FormMultipart`,
  can be called by `c.ShouldBind()` multiple times without any damage to
  performance (See [#1341](https://github.com/gin-gonic/gin/pull/1341)).
  
  ### http2 server push
  
  http.Pusher is supported only **go1.8+**. See the [golang blog](https://blog.golang.org/h2push) for detail information.
  
  ```go
  package main
  
  import (
  	"html/template"
  	"log"
  
  	"github.com/gin-gonic/gin"
  )
  
  var html = template.Must(template.New("https").Parse(`
  <html>
  <head>
    <title>Https Test</title>
    <script src="/assets/app.js"></script>
  </head>
  <body>
    <h1 style="color:red;">Welcome, Ginner!</h1>
  </body>
  </html>
  `))
  
  func main() {
  	r := gin.Default()
  	r.Static("/assets", "./assets")
  	r.SetHTMLTemplate(html)
  
  	r.GET("/", func(c *gin.Context) {
  		if pusher := c.Writer.Pusher(); pusher != nil {
  			// use pusher.Push() to do server push
  			if err := pusher.Push("/assets/app.js", nil); err != nil {
  				log.Printf("Failed to push: %v", err)
  			}
  		}
  		c.HTML(200, "https", gin.H{
  			"status": "success",
  		})
  	})
  
  	// Listen and Server in https://127.0.0.1:8080
  	r.RunTLS(":8080", "./testdata/server.pem", "./testdata/server.key")
  }
  ```
  
  ### Define format for the log of routes
  
  The default log of routes is:
  ```
  [GIN-debug] POST   /foo                      --> main.main.func1 (3 handlers)
  [GIN-debug] GET    /bar                      --> main.main.func2 (3 handlers)
  [GIN-debug] GET    /status                   --> main.main.func3 (3 handlers)
  ```
  
  If you want to log this information in given format (e.g. JSON, key values or something else), then you can define this format with `gin.DebugPrintRouteFunc`.
  In the example below, we log all routes with standard log package but you can use another log tools that suits of your needs.
  ```go
  import (
  	"log"
  	"net/http"
  
  	"github.com/gin-gonic/gin"
  )
  
  func main() {
  	r := gin.Default()
  	gin.DebugPrintRouteFunc = func(httpMethod, absolutePath, handlerName string, nuHandlers int) {
  		log.Printf("endpoint %v %v %v %v
  ", httpMethod, absolutePath, handlerName, nuHandlers)
  	}
  
  	r.POST("/foo", func(c *gin.Context) {
  		c.JSON(http.StatusOK, "foo")
  	})
  
  	r.GET("/bar", func(c *gin.Context) {
  		c.JSON(http.StatusOK, "bar")
  	})
  
  	r.GET("/status", func(c *gin.Context) {
  		c.JSON(http.StatusOK, "ok")
  	})
  
  	// Listen and Server in http://0.0.0.0:8080
  	r.Run()
  }
  ```
  
  ### Set and get a cookie
  
  ```go
  import (
      "fmt"
  
      "github.com/gin-gonic/gin"
  )
  
  func main() {
  
      router := gin.Default()
  
      router.GET("/cookie", func(c *gin.Context) {
  
          cookie, err := c.Cookie("gin_cookie")
  
          if err != nil {
              cookie = "NotSet"
              c.SetCookie("gin_cookie", "test", 3600, "/", "localhost", false, true)
          }
  
          fmt.Printf("Cookie value: %s 
  ", cookie)
      })
  
      router.Run()
  }
  ```
  
  
  ## Testing
  
  The `net/http/httptest` package is preferable way for HTTP testing.
  
  ```go
  package main
  
  func setupRouter() *gin.Engine {
  	r := gin.Default()
  	r.GET("/ping", func(c *gin.Context) {
  		c.String(200, "pong")
  	})
  	return r
  }
  
  func main() {
  	r := setupRouter()
  	r.Run(":8080")
  }
  ```
  
  Test for code example above:
  
  ```go
  package main
  
  import (
  	"net/http"
  	"net/http/httptest"
  	"testing"
  
  	"github.com/stretchr/testify/assert"
  )
  
  func TestPingRoute(t *testing.T) {
  	router := setupRouter()
  
  	w := httptest.NewRecorder()
  	req, _ := http.NewRequest("GET", "/ping", nil)
  	router.ServeHTTP(w, req)
  
  	assert.Equal(t, 200, w.Code)
  	assert.Equal(t, "pong", w.Body.String())
  }
  ```
  
  ## Users
  
  Awesome project lists using [Gin](https://github.com/gin-gonic/gin) web framework.
  
  * [gorush](https://github.com/appleboy/gorush): A push notification server written in Go.
  * [fnproject](https://github.com/fnproject/fn): The container native, cloud agnostic serverless platform.
  * [photoprism](https://github.com/photoprism/photoprism): Personal photo management powered by Go and Google TensorFlow.
  * [krakend](https://github.com/devopsfaith/krakend): Ultra performant API Gateway with middlewares.
  * [picfit](https://github.com/thoas/picfit): An image resizing server written in Go.