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

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

	// 使用默认中间件创建一个gin路由器
	// logger and recovery (crash-free) 中间件
	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)

	// 默认启动的是 8080端口，也可以自己定义启动端口
	router.Run()
	// router.Run(":3000") for a hard coded port
}

获取路径中的参数

func main() {
	router := gin.Default()

	// 此规则能够匹配/user/john这种格式，但不能匹配/user/ 或 /user这种格式
	router.GET("/user/:name", func(c *gin.Context) {
		name := c.Param("name")
		c.String(http.StatusOK, "Hello %s", name)
	})

	// 但是，这个规则既能匹配/user/john/格式也能匹配/user/john/send这种格式
	// 如果没有其他路由器匹配/user/john，它将重定向到/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 Get 参数

func main() {
	router := gin.Default()

	// 匹配的url格式:  /welcome?firstname=Jane&lastname=Doe
	router.GET("/welcome", func(c *gin.Context) {
		firstname := c.DefaultQuery("firstname", "Guest")
		lastname := c.Query("lastname") // 是 c.Request.URL.Query().Get("lastname") 的简写

		c.String(http.StatusOK, "Hello %s %s", firstname, lastname)
	})
	router.Run(":8080")
}

获取 Post 参数

func main() {
	router := gin.Default()

	router.POST("/form_post", func(c *gin.Context) {
		message := c.PostForm("message")
		nick := c.DefaultPostForm("nick", "anonymous") // 此方法可以设置默认值

		c.JSON(200, gin.H{
			"status":  "posted",
			"message": message,
			"nick":    nick,
		})
	})
	router.Run(":8080")
}

Get + Post 混合

示例：
POST /post?id=1234&page=1 HTTP/1.1
Content-Type: application/x-www-form-urlencoded

name=manu&message=this_is_great
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")
}

结果：id: 1234; page: 1; name: manu; message: this_is_great

上传文件

上传文件的文件名可以由用户自定义，所以可能包含非法字符串，为了安全起见，应该由服务端统一文件名规则

func main() {
	router := gin.Default()
	// 给表单限制上传大小 (默认 32 MiB)
	// router.MaxMultipartMemory = 8 << 20  // 8 MiB
	router.POST("/upload", func(c *gin.Context) {
		// 单文件
		file, _ := c.FormFile("file")
		log.Println(file.Filename)

		// 上传文件到指定的路径
		// c.SaveUploadedFile(file, dst)

		c.String(http.StatusOK, fmt.Sprintf("'%s' uploaded!", file.Filename))
	})
	router.Run(":8080")
}

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

多文件上传

func main() {
	router := gin.Default()
	// 给表单限制上传大小 (默认 32 MiB)
	// router.MaxMultipartMemory = 8 << 20  // 8 MiB
	router.POST("/upload", func(c *gin.Context) {
		// 多文件
		form, _ := c.MultipartForm()
		files := form.File["upload[]"]

		for _, file := range files {
			log.Println(file.Filename)

			// 上传文件到指定的路径
			// c.SaveUploadedFile(file, dst)
		}
		c.String(http.StatusOK, fmt.Sprintf("%d files uploaded!", len(files)))
	})
	router.Run(":8080")
}

curl 测试： 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"

路由分组

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")
}

无中间件启动

使用

r := gin.New()

代替

// 默认启动方式，包含 Logger、Recovery 中间件
r := gin.Default()

使用中间件

func main() {
	// 创建一个不包含中间件的路由器
	r := gin.New()

	// 全局中间件
	// 使用 Logger 中间件
	r.Use(gin.Logger())

	// 使用 Recovery 中间件
	r.Use(gin.Recovery())

	// 路由添加中间件，可以添加任意多个
	r.GET("/benchmark", MyBenchLogger(), benchEndpoint)

	// 路由组中添加中间件
	// 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")
}

写日志文件

func main() {
    // 禁用控制台颜色
    gin.DisableConsoleColor()

    // 创建记录日志的文件
    f, _ := os.Create("gin.log")
    gin.DefaultWriter = io.MultiWriter(f)

    // 如果需要将日志同时写入文件和控制台，请使用以下代码
    // gin.DefaultWriter = io.MultiWriter(f, os.Stdout)

    router := gin.Default()
    router.GET("/ping", func(c *gin.Context) {
        c.String(200, "pong")
    })

    router.Run(":8080")
}

自定义日志格式

func main() {
	router := gin.New()

	// LoggerWithFormatter 中间件会将日志写入 gin.DefaultWriter
	// By default gin.DefaultWriter = os.Stdout
	router.Use(gin.LoggerWithFormatter(func(param gin.LogFormatterParams) string {

		// 你的自定义格式
		return fmt.Sprintf("%s - [%s] \"%s %s %s %d %s \"%s\" %s\"\n",
				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")
}

::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" "

模型绑定和验证

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

Gin 使用 go-playground/validator.v8 验证参数，查看完整文档。

需要在绑定的字段上设置 tag，比如，绑定格式为 json，需要这样设置 json:"fieldname" 。

此外，Gin 还提供了两套绑定方法：

• Must bind

  • Methods - Bind, BindJSON, BindXML, BindQuery, BindYAML
  • Behavior - 这些方法底层使用 MustBindWith，如果存在绑定错误，请求将被以下指令中止 c.AbortWithError(400, err).SetType(ErrorTypeBind)，响应状态代码会被设置为 400，请求头 Content-Type 被设置为 text/plain; charset=utf-8。注意，如果你试图在此之后设置响应代码，将会发出一个警告 [GIN-debug][warning] Headers were already written. Wanted to override status code 400 with 422，如果你希望更好地控制行为，请使用 ShouldBind 相关的方法

• Should bind

  • Methods - ShouldBind, ShouldBindJSON, ShouldBindXML, ShouldBindQuery, ShouldBindYAML
  • Behavior - 这些方法底层使用 ShouldBindWith，如果存在绑定错误，则返回错误，开发人员可以正确处理请求和错误。

当我们使用绑定方法时，Gin 会根据 Content-Type 推断出使用哪种绑定器，如果你确定你绑定的是什么，你可以使用 MustBindWith 或者 BindingWith。

你还可以给字段指定特定规则的修饰符，如果一个字段用 binding:"required"修饰，并且在绑定时该字段的值为空，那么将返回一个错误。

// 绑定为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")
}

请求示例：

$ 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"}

跳过验证：
当使用上面的 curl 命令运行上面的示例时，返回错误，因为示例中 Password 字段使用了 binding:"required"，如果我们使用 binding:"-"，那么它就不会报错。

验证提示汉化

package main

import (
	"fmt"
	"github.com/gin-gonic/gin"
	"github.com/gin-gonic/gin/binding"
	"github.com/go-playground/locales/en"
	"github.com/go-playground/locales/zh"
	ut "github.com/go-playground/universal-translator"
	"github.com/go-playground/validator/v10"
	en_translation "github.com/go-playground/validator/v10/translations/en"
	zh_translation "github.com/go-playground/validator/v10/translations/zh"
	"net/http"
	"reflect"
	"strings"
)

var trans ut.Translator

type LoginForm struct {
	Username   string `json:"username" binding:"required,min=6,max=10"`
	Password   string `json:"password" binding:"required"`
	Email      string `json:"email" binding:"required,email"`
	Repassword string `json:"repassword" binding:"required,eqfield=Password"`
}

func removeTopStruct(fields map[string]string)map[string]string{
    rsp:=map[string]string{}
    for field,err:=range fields{
    	rsp[field[strings.Index(field,".")+1:]]=err
	}
	return rsp
}

func InitTrans(locale string) (err error) {
	if v, ok := binding.Validator.Engine().(*validator.Validate); ok {
		//注册一个获取json的tag的方法
		v.RegisterTagNameFunc(func(fld reflect.StructField)string{
			name:= strings.SplitN(fld.Tag.Get("json"),",",2)[0]
			if name=="-"{
				return ""
			}
			return name
		})

		zhT := zh.New() //中文翻译器
		enT := en.New() //英文翻译器
		//第一个参数为备用语言环境，剩下了两个为必须支持的语言环境
		uni := ut.New(enT, zhT, enT)
		trans, ok = uni.GetTranslator(locale)
		if !ok {
			return fmt.Errorf("uni.GetTranslator(%s)", locale)
		}
		switch locale {
		case "en":
			en_translation.RegisterDefaultTranslations(v, trans)
		case "zh":
			zh_translation.RegisterDefaultTranslations(v, trans)
		default:
			en_translation.RegisterDefaultTranslations(v, trans)
		}
	}
	return
}



func main() {
	//验证器
	if err:=InitTrans("zh");err!=nil{
		fmt.Println("初始翻译器错误！")
		return
	}
	router := gin.Default()
	var LoginForm LoginForm
	router.POST("/hello", func(ctx *gin.Context) {
		if err := ctx.ShouldBind(&LoginForm); err != nil {
			errs,ok:=err.(validator.ValidationErrors)
			if !ok{
				ctx.JSON(http.StatusOK, gin.H{
					"message": err.Error(),
				})
			}
			ctx.JSON(http.StatusBadRequest, gin.H{
				"error": removeTopStruct(errs.Translate(trans)),
			})
			return
		}
		ctx.JSON(http.StatusOK, gin.H{
			"message": "注册成功！",
		})
	})
	router.Run()
}

自定义验证器

v8 版本

Gin 允许我们自定义参数验证器，参考 1，参考 2，参考 3

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()})
	}
}

$ 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"}

v10 版本

package validator

import (
	"regexp"

	"github.com/go-playground/validator/v10"
)

func ValidateMobile(fl validator.FieldLevel) bool {
	mobile := fl.Field().String()
	//使用正则表达式判断是否合法
	ok, _ := regexp.MatchString(`^1([38][0-9]|14[579]|5[^4]|16[6]|7[1-35-8]|9[189])\d{8}$`, mobile)
	if !ok{
		return false
	}
	return true
}

//注册验证器
	if v, ok := binding.Validator.Engine().(*validator.Validate); ok {
		_ = v.RegisterValidation("mobile", myvalidator.ValidateMobile)
		_ = v.RegisterTranslation("mobile", global.Trans, func(ut ut.Translator) error {
			return ut.Add("mobile", "{0} 非法的手机号码!", true) // see universal-translator for details
		}, func(ut ut.Translator, fe validator.FieldError) string {
			t, _ := ut.T("mobile", fe.Field())
			return t
		})
	}

只绑定 Get 参数

ShouldBindQuery 函数只绑定 Get 参数，不绑定 post 数据

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")
}

绑定 Get 参数或者 Post 参数

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.
	// 如果是Get，那么接收不到请求中的Post的数据？？
	// 如果是Post, 首先判断 `content-type` 的类型 `JSON` or `XML`, 然后使用对应的绑定器获取数据.
	// 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")
}

绑定 uri

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")
}

测试用例：

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

绑定 HTML 复选框

main.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

<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"]}

绑定 Post 参数

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")
}

测试用例：

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

XML、JSON、YAML 和 ProtoBuf 渲染（输出格式）

即接口返回的数据格式

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 可以防止 json 劫持，如果返回的数据是数组，则会默认在返回值前加上"while(1)"

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

	// 可以自定义返回的json数据前缀
	// r.SecureJsonPrefix(")]}',\n")

	r.GET("/someJSON", func(c *gin.Context) {
		names := []string{"lena", "austin", "foo"}

		// 将会输出:   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 可以跨域传输，如果参数中存在回调参数，那么返回的参数将是回调函数的形式

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

	r.GET("/JSONP", func(c *gin.Context) {
		data := map[string]interface{}{
			"foo": "bar",
		}

		// 访问 http://localhost:8080/JSONP?callback=call
		// 将会输出:   call({foo:"bar"})
		c.JSONP(http.StatusOK, data)
	})

	// Listen and serve on 0.0.0.0:8080
	r.Run(":8080")
}

AsciiJSON

使用 AsciiJSON 将使特殊字符编码

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

	r.GET("/someJSON", func(c *gin.Context) {
		data := map[string]interface{}{
			"lang": "GO语言",
			"tag":  "<br>",
		}

		// 将输出: {"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

通常情况下，JSON 会将特殊的 HTML 字符替换为对应的 unicode 字符，比如<替换为\u003c，如果想原样输出 html，则使用 PureJSON，这个特性在 Go 1.6 及以下版本中无法使用。

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")
}

设置静态文件路径

访问静态文件需要先设置路径

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")
}

返回第三方获取的数据

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() 或者 LoadHTMLFiles()

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>
	<h1>
		{{ .title }}
	</h1>
</html>

在不同目录中使用具有相同名称的模板

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

{{ define "posts/index.tmpl" }}
<html><h1>
	{{ .title }}
</h1>
<p>Using posts/index.tmpl</p>
</html>
{{ end }}

templates/users/index.tmpl

{{ define "users/index.tmpl" }}
<html><h1>
	{{ .title }}
</h1>
<p>Using users/index.tmpl</p>
</html>
{{ end }}

自定义模板渲染器

import "html/template"

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

自定义渲染分隔符

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

自定义模板函数
main.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
然后就可以在 html 中直接使用 formatAsDate 函数了

Date: {[{.now | formatAsDate}]}

Result:

Date: 2017/07/01

重定向

发布 HTTP 重定向很容易，支持内部和外部链接

r.GET("/test", func(c *gin.Context) {
	c.Redirect(http.StatusMovedPermanently, "http://www.google.com/")
})

Gin 路由重定向，使用如下的 HandleContext

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

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")
}

使用 BasicAuth()（验证）中间件

// 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")
}

中间件中使用 Goroutines

在中间件或处理程序中启动新的 Goroutines 时，你不应该使用其中的原始上下文，你必须使用只读副本（c.Copy()）

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

	r.GET("/long_async", func(c *gin.Context) {
		// 创建要在goroutine中使用的副本
		cCp := c.Copy()
		go func() {
			// simulate a long task with time.Sleep(). 5 seconds
			time.Sleep(5 * time.Second)

			// 这里使用你创建的副本
			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)

		// 这里没有使用goroutine，所以不用使用副本
		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

直接像这样使用 http.ListenAndServe()

func main() {
	router := gin.Default()
	http.ListenAndServe(":8080", router)
}

或者

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()
}

支持 Let's Encrypt 证书

1 行代码实现 LetsEncrypt HTTPS 服务器

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"))
}

自定义 autocert 管理器的示例

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))
}

Gin 运行多个服务

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

想要优雅地重启或停止你的 Web 服务器，使用下面的方法

我们可以使用 fvbock/endless 来替换默认的 ListenAndServe，有关详细信息，请参阅问题＃296

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

一个替换方案

• manners：一个 Go HTTP 服务器，能优雅的关闭
• graceful：Graceful 是一个 go 的包，支持优雅地关闭 http.Handler 服务器
• grace：对 Go 服务器进行优雅的重启和零停机部署

如果你的 Go 版本是 1.8，你可能不需要使用这个库，考虑使用 http.Server 内置的 Shutdown()方法进行优雅关闭，查看例子

// +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")
}

构建包含模板的二进制文件

你可以使用 go-assets 将服务器构建成一个包含模板的二进制文件

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
}

使用自定义结构绑定表单数据

以下示例使用自定义结构

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()
}

运行示例：

$ 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：不支持以下样式结构

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
}

总之，现在只支持现在没有 form 标签的自定义结构

将请求体绑定到不同的结构体中

绑定请求体的常规方法使用 c.Request.Body，并且不能多次调用

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 {
    ...
  }
}

同样，你能使用 c.ShouldBindBodyWith

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 在绑定之前将 body 存储到上下文中，这对性能有轻微影响，因此如果你要立即调用，则不应使用此方法
• 此功能仅适用于这些格式 -- JSON, XML, MsgPack, ProtoBuf。对于其他格式，Query, Form, FormPost, FormMultipart, 可以被 c.ShouldBind()多次调用而不影响性能（参考 #1341）

HTTP/2 服务器推送

http.Pusher 只支持 Go 1.8 或更高版本

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")
}

自定义路由日志的格式

默认的路由日志是这样的：

[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)

如果你想以给定的格式记录这些信息（例如 JSON，键值对或其他格式），你可以使用 gin.DebugPrintRouteFunc 来定义格式，在下面的示例中，我们使用标准日志包记录路由日志，你可以使用其他适合你需求的日志工具

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()
}

设置并获取 cookie

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

net/http/httptest 包是 http 测试的首选方式

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")
}

测试上面的示例代码

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())
}

JWT