gin/README_ZH.md

# Gin Web 框架中文文档

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Gin 是一个 Go (Golang) 语言框架。 它是一个拥有更好性能的 martini-like API 框架, 比 [httprouter](https://github.com/julienschmidt/httprouter) 的速度快了40倍. 如果你是性能和高效的追求者, 那么你会爱上 Gin.

![Gin console logger](https://gin-gonic.github.io/gin/other/console.png)

## Contents

- [安装](#安装)
- [前提条件](#前提条件)
- [快速开始](#快速开始)
- [性能测试](#性能测试)
- [Gin v1 稳定版](#gin-v1-稳定版)
- [使用 jsoniter ](#使用-jsoniter)
- [API 示例](#api-示例)
    - [GET,POST,PUT,PATCH,DELETE,OPTIONS 使用](#get-post-put-patch-delete-options-使用)
    - [获取路由参数](#获取路由参数)
    - [获取url查询参数](#获取url查询参数)
    - [Multipart Urlencoded 表单](#multipart-urlencoded-表单)
    - [获取post表单数据（url带查询参数）](#获取post表单数据url带查询参数)
    - [映射参数 表单参数](#映射参数-表单参数)
    - [上传文件](#上传文件)
    - [路由组](#路由组)
    - [默认初始化 Gin](#默认初始化-gin)
    - [使用中间件](#使用中间件)
    - [如何记录日志](#如何记录日志)
    - [模型绑定和验证](#模型绑定和验证)
    - [自定义验证器](#自定义验证器)
    - [只绑定url查询参数](#只绑定url查询参数)
    - [url查询参数或表单数据绑定到结构体](#url查询参数或表单数据绑定到结构体)
    - [url路径参数绑定](#url路径参数绑定)
    - [绑定 HTML 复选框](#绑定-html-复选框)
    - [Multipart Urlencoded 绑定](#multipart-urlencoded-绑定)
    - [XML JSON YAML ProtoBuf 渲染](#xml-json-yaml-protobuf-渲染)
    - [SecureJSON](#SecureJSON)
    - [静态文件服务](#静态文件服务)
    - [从reader 读取数据](#从-reader-读取数据)
    - [HTML 渲染](#html-渲染)
    - [多模板](#多模板)
    - [重定向](#重定向)
    - [自定义中间件](#自定义中间件)
    - [使用 BasicAuth() 中间件](#使用-basicauth()-中间件)
    - [在中间件中使用Goroutines](#在中间件中使用Goroutines)
    - [自定义 HTTP 配置](#自定义-http-配置)
    - [Let's Encrypt 支持](#lets-encrypt-支持)
    - [使用 Gin 运行多个服务](使用-gin-运行多个服务)
    - [优雅重启或停止](#优雅重启或停止)
    - [静态资源嵌入](#静态资源嵌入)
    - [表单数据绑定到自定义结构体](#表单数据绑定到自定义结构体)
    - [将request body绑定到不同的结构体中](#将request-body绑定到不同的结构体中)
    - [http2 server 推送](#http2-server-推送)
    - [定义路由日志的格式](#定义路由日志的格式)
    - [如何使用Cookie](#如何使用Cookie)
- [测试](#测试)
- [用户](#用户)

## 安装

要安装 Gin 软件包，需要先安装 Go 并设置 Go 工作区。

1. 下载并安装 gin:

```sh
$ go get -u github.com/gin-gonic/gin
```

2. 将 gin 引入到代码中:

```go
import "github.com/gin-gonic/gin"
```

3. （可选）如果使用诸如`http.StatusOK`之类的常量，则需要引入 `net/http` 包。

```go
import "net/http"
```

### 使用 [Govendor](https://github.com/kardianos/govendor) 工具创建项目

1. `go get` govendor

```sh
$ go get github.com/kardianos/govendor
```
2.创建项目并且 `cd` 到项目目录中

```sh
$ mkdir -p $GOPATH/src/github.com/myusername/project && cd "$_"
```

3. 使用 govendor 初始化项目,并且引入gin

```sh
$ govendor init
$ govendor fetch github.com/gin-gonic/gin@v1.3
```

4. 复制启动文件模板到项目目录中

```sh
$ curl https://raw.githubusercontent.com/gin-gonic/gin/master/examples/basic/main.go > main.go
```

5.启动项目

```sh
$ go run main.go
```

## 前提条件

新版本的 Gin 需要 Go 1.6 或者更高版本，并且很快就会要求升级到 Go 1.7.

## 快速开始
 
```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
```

## 性能测试

Gin 使用自定义版本的 [HttpRouter](https://github.com/julienschmidt/httprouter)

[所有性能测试](/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): 在不断的时间内实现总重复，更高意味着更自信的结果
- (2): 单次重复持续时间（ns / op），越低越好
- (3): 堆内存（B / op），越低越好
- (4): 每次重复的平均分配（allocs / op）越低越好

## Gin v1 稳定版

- [x] 零分配路由。
- [x] 仍然是最快的http路由器和框架。
- [x] 完整的单元测试支持
- [x] 对战测试
- [x] API冻结，使用新版本不需要修改原有代码。

## 使用 [jsoniter](https://github.com/json-iterator/go) 

Gin默认使用`encoding/json`解析json数据，但您可以通过`go build -tags=`更改为使用[jsoniter](https://github.com/json-iterator/go)。

```sh
$ go build -tags=jsoniter .
```

## API 示例

### 使用GET, POST, PUT, PATCH, DELETE , OPTIONS 

```go
func main() {
	// Disable Console Color
	// gin.DisableConsoleColor()

	// 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
}
```

### 获取路由参数

```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")
}
```

### 获取url查询参数

```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 表单

```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")
}
```

### 获取post表单数据(url带查询参数)

```
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
```

### 映射参数 表单参数

```
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]
```

### 上传文件

#### 单个文件上传

参考问题[＃774](https://github.com/gin-gonic/gin/issues/774)和详细[示例代码](examples/upload-file/single)。

```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")
}
```

`curl`示例:

```bash
curl -X POST http://localhost:8080/upload \
  -F "file=@/Users/appleboy/test.zip" \
  -H "Content-Type: multipart/form-data"
```

#### 多文件上传

查看详细信息[示例代码](examples/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")
}
```

`curl`示例:

```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"
```

### 路由组

```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")
}
```

### 默认初始化 Gin

用

```go
r := gin.New()
```

代替

```go
// Default With the Logger and Recovery middleware already attached
r := gin.Default()
```


### 使用中间件
```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")
}
```

### 如何记录日志
```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")
}
```

### 模型绑定和验证

要将请求主体绑定到结构体中，请使用模型绑定。Gin目前支持JSON、XML、YAML和标准表单值的绑定（foo=bar＆boo=baz）。

Gin使用[go-playground/validator.v8](https://github.com/go-playground/validator)进行验证。[完整文档](http://godoc.org/gopkg.in/go-playground/validator.v8#hdr-Baked_In_Validators_and_Tags)。

使用时，需要在要绑定的所有字段上，设置相应的tag。例如，使用JSON绑定时，字段tag设置为`json:"fieldname"`。

Gin提供了两类绑定方法：
- **MustBind** - 
   - **方法** - `Bind`, `BindJSON`, `BindXML`, `BindQuery`, `BindYAML`
   - **说明** - 这些方法属于`MustBindWith`的具体调用。如果发生绑定错误，则请求终止，并触发`c.AbortWithError(400,err).SetType(ErrorTypeBind)`。响应状态码被设置为400，`Content-Type`被设置为`text/plain;charset= UTF-8`。如果您在此之后尝试设置响应状态码，Gin会输出日志“ `[GIN-debug] [WARNING] Headers were already written. Wanted to override status code 400 with 422`。如果您希望更好地把控绑定，请考虑使用`ShouldBind`等效方法。
- **ShouldBind** - 
   - **方法** - `ShouldBind`，`ShouldBindJSON`，`ShouldBindXML`，`ShouldBindQuery`
   - **说明** - 这些方法属于`ShouldBindWith`的具体调用。如果发生绑定错误，Gin会返回错误。由您处理错误以及请求。

使用Bind方法时，Gin会根据Content-Type尝试推断如何绑定，如果您明确知道，您可以使用 `MustBindWith` 或 `ShouldBindWith`。

指定必须绑定的字段，在该字段Tag上加上`binding:"required"` ，如果绑定时是空值，Gin会报错。

```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</user>
	//	</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")
}
```

**测试**
```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"}
```

**忽略验证**

使用`curl` 命令运行上面的例子时，它返回错误，因为这个例子使用`binding:"required"` 。 如果使用 `binding:"-"` ，那么再次运行上面的例子时它不会返回错误。

### 自定义验证器

注册自定义验证器， 请参阅[示例代码](examples/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"}
```

结构体验证也可以参考[这种方法](https://github.com/go-playground/validator/releases/tag/v8.7)注册。
请参阅[struct-lvl-validation示例](examples/struct-lvl-validations)以了解更多信息。

### 只绑定url查询参数

`ShouldBindQuery` 函数只绑定url查询参数而不是post字段。 请参阅[详细信息](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")
}

```

### url查询参数或表单数据绑定到结构体

请参阅[详细信息](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")
}
```

测试:
```sh
$ curl -X GET "localhost:8085/testing?name=appleboy&address=xyz&birthday=1992-03-15"
```
### url路径参数绑定

查看[详细信息](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")
}
```

测试:
```sh
$ curl -v localhost:8088/thinkerou/987fbc97-4bed-5078-9f07-9141ba07c9f3
$ curl -v localhost:8088/thinkerou/not-uuid
```

### 绑定 HTML 复选框

参见[详细信息](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 绑定

```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")
}
```

测试:
```sh
$ curl -v --form user=user --form password=password http://localhost:8080/login
```

### XML JSON YAML ProtoBuf 渲染

```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

使用 SecureJSON 来防止 json 劫持。 如果给定的结构是数组值，则默认预 置`“while(1)，”` 到响应体。

```go
func main() {
	r := gin.Default()

	// You can also use your own secure json prefix
	// r.SecureJsonPrefix(")]}',\n")

	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

使用 JSONP 从不同域中的服务器请求数据。 如果查询参数回调存在，则将回调添加到响应正文。

```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

使用 Ascii JSON 生成具有转义的非 ASCII 字符的仅 ASCII JSON。

```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

通常，JSON使用unicode替换特殊HTML字符，例如 `<` 变为 `\ u003c`。 如果要按字面意思对这些字符进行编码，则可以使用 PureJSON。
Go 1.6及更低版本无法使用此功能。

```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)
}
```

### 静态文件服务

```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")
}
```

### 从 reader 读取数据

```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 渲染

使用LoadHTMLGlob()或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>
```

在不同目录中使用具有相同名称的模板

```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 }}
```

#### 自定义模板渲染器

您还可以使用自己的 html 模板渲染

```go
import "html/template"

func main() {
	router := gin.Default()
	html := template.Must(template.ParseFiles("file1", "file2"))
	router.SetHTMLTemplate(html)
	router.Run(":8080")
}
```

#### 自定义分隔符

您可以使用自定义分隔

```go
	r := gin.Default()
	r.Delims("{[{", "}]}")
	r.LoadHTMLGlob("/path/to/templates")
```

#### 自定义模板功能

查看详细信息[示例代码](examples/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
日期: {[{.now | formatAsDate}]}
```

结果:
```
Date: 2017/07/01
```

### 多模板

Gin 允许默认只使用一个 html 模板。 检查[多模板渲染](https://github.com/gin-contrib/multitemplate)以使用 go 1.6 `block template` 等功能。

### 重定向

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/")
})
```


发出路由器重定向，使用如下的“HandleContext”。

``` 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"})
})
```


###  自定义中间件

```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")
}
```

### BasicAuth() 中间件

```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")
}
```

###  在中间件中使用Goroutines

当在中间件或handler中启动新的Goroutines时，不能使用原始上下文，必须使用只读副本。

```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")
}
```

### 自定义 HTTP 配置

直接使用`http.ListenAndServe()`，如下所示：

```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()
}
```

###  Let's Encrypt 支持

一行代码支持 LetsEncrypt HTTPS示例。

[embedmd]:# (examples/auto-tls/example1/main.go go)
```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"))
}
```

autocert使用示例。

[embedmd]:# (examples/auto-tls/example2/main.go go)
```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))
}
```

### 使用 Gin 运行多个服务

请参阅[问题](https://github.com/gin-gonic/gin/issues/346)并尝试以下示例：

[embedmd]:# (examples/multiple-service/main.go go)
```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)
	}
}
```

### 优雅重启或停止

您想要优雅地重启或停止您的Web服务器吗？
有一些方法可以做到这一点。

我们可以使用[fvbock/endless](https://github.com/fvbock/endless)来替换默认的`ListenAndServe`。 有关更多详细信息，请参阅问题[＃296](https://github.com/gin-gonic/gin/issues/296)。

```go
router := gin.Default()
router.GET("/", handler)
// [...]
endless.ListenAndServe(":4242", router)
```

替代方案：

* [manners](https://github.com/braintree/manners)：礼貌的Go HTTP服务器，可以正常关闭。
* [graceful](https://github.com/tylerb/graceful)：Graceful是一个Go包，可以正常关闭http.Handler服务器。
* [grace](https://github.com/facebookgo/grace)：Go服务器的平滑重启和零停机时间部署。

如果您使用的是Go 1.8，可以考虑使用http.Server的内置[Shutdown()](https://golang.org/pkg/net/http/#Server.Shutdown)方法进行正常关机。
请参阅gin的完整[graceful-shutdown](/examples /graceful-shutdown)示例。

[embedmd]:# (examples/graceful-shutdown/graceful-shutdown/server.go go)
```go
// +build go1.8

package main

import (
	"context"
	"log"
	"net/http"
	"os"
	"os/signal"
	"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\n", err)
		}
	}()

	// Wait for interrupt signal to gracefully shutdown the server with
	// a timeout of 5 seconds.
	quit := make(chan os.Signal)
	signal.Notify(quit, os.Interrupt)
	<-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)
	}
	log.Println("Server exiting")
}
```

### 静态资源嵌入

使用[go-assets](https://github.com/jessevdk/go-assets)将静态资源打包到可执行文件中。

```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
}
```

请参阅`examples/assets-in-binary`目录中的完整示例。

### 表单数据绑定到自定义结构体

以下示例使用自定义结构体：

```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()
}
```

`curl`命令示例：

```
$ 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"}}
```

**注意**:不支持以下格式结构体：

```go
type StructX struct {
    X struct {} `form:"name_x"` // HERE have form
}

type StructY struct {
    Y StructX `form:"name_y"` // HERE have form
}

type StructZ struct {
    Z *StructZ `form:"name_z"` // HERE have form
}
```

一句话，现在只支持没有`form`的嵌套结构体。

### 将request body绑定到不同的结构体中

一般通过调用`c.Request.Body`方法绑定数据，但不能多次调用这个方法。

```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 {
    ...
  }
}
```

为此，要想多次绑定，需要使用`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`会在绑定之前将body存储到上下文中。 这会对性能造成轻微影响，如果调用一次就能完成绑定的话，那就不要用这个方法。
* 只有某些格式需要此功能 ，如`JSON`、`XML`、`MsgPack`、`ProtoBuf`。 对于其他格式，如`Query`、`Form`、`FormPost`、`FormMultipart`可以多次调用`c.ShouldBind()`而不会造成任任何性能损失（见[＃1341](https://github.com/gin-gonic/gin/pull/1341)）。

### http2 server 推送


http.Pusher仅支持go1.8 +。 有关详细信息，请参阅[golang blog](https://blog.golang.org/h2push)。

[embedmd]:# (examples/http-pusher/main.go go)
```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")
}
```

### 定义路由日志的格式

默认的路由日志格式：
```
[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)
```

如果要以指的格式（例如JSON，Key Values或其他格式）记录信息，则可以使用`gin.DebugPrintRouteFunc`指定格式。
在下面的示例中，我们使用标准日志包记录所有路由，但您可以使用其他满足需求的日志工具。
```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\n", 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()
}
```
### 如何使用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 \n", cookie)
    })

    router.Run()
}
```

## 测试

HTTP测试首选`net/http/httptest`包。

```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")
}
```

上面这段代码的测试用例：

```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())
}
```

## 用户
使用[Gin](https://github.com/gin-gonic/gin)框架的著名项目：

* [drone](https://github.com/drone/drone)：用Go编写的基于docker的持续集成平台。
* [gorush](https://github.com/appleboy/gorush)：用Go编写的推送通知服务。
* [fnproject](https://github.com/fnproject/fn)：容器驱动、云无关的无服务器平台。
* [photoprism](https://github.com/photoprism/photoprism): 用Go编写的基于TensorFlow的个人相册管理系统.
* [krakend](https://github.com/devopsfaith/krakend): 表现优异的API网关中间件。