Go语言gin框架简易入门文档

安装

要安装 Gin 包，您需要先安装 Go 并设置 Go 工作区。

第一个需要 Go 安装（版本 1.11+是必需的），然后您可以使用下面的 Go 命令来安装 Gin。

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

在代码中导入它：

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

可选导入 net/http. 例如，如果使用http.StatusOK这样的常量，这是必需的。

import "net/http"

快速入门

# assume the following codes in example.go file
$ cat example.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 (for windows "localhost:8080")
}
# run example.go and visit 0.0.0.0:8080/ping (for windows "localhost:8080/ping") on browser
$ go run example.go

使用jsoniter 构建

Gin 用作默认 json 包，但您可以通过从其他标记生成更改为 jsoniter。encoding/json

$ go build -tags=jsoniter .

API 示例

您可以在Gin示例存储库中找到许多现成的示例。

快速构建RESTful风格接口

GET, POST, PUT, PATCH, DELETE

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
}

请求路径中的参数

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)
    })

    // For each matched request Context will hold the route definition
    router.POST("/user/:name/*action", func(c *gin.Context) {
        c.FullPath() == "/user/:name/*action" // true
    })

    router.Run(":8080")
}

查询字符串参数

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

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")
}

query 和 post 表单

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")
}
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

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]

文件上传

单文件

文件名始终是可选的，应用程序不能盲目使用：应删除路径信息，并完成对服务器文件系统规则的转换。

func main() {
    router := gin.Default()
    // 设置允许上传文件的大小,默认是32M
    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")
}

请求示例:

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

多文件上传

详细示例 : example code.

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")
}

请求示例:

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

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")
}

使用无默认中间件的gin框架

使用如下:

r := gin.New()

而不是

// 已经附加了日志记录器和恢复中间件
r := gin.Default()

使用中间件

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")

自定义恢复中间件

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.CustomRecovery(func(c *gin.Context, recovered interface{}) {
        if err, ok := recovered.(string); ok {
            c.String(http.StatusInternalServerError, fmt.Sprintf("error: %s", err))
        }
        c.AbortWithStatus(http.StatusInternalServerError)
    }))

    r.GET("/panic", func(c *gin.Context) {
        // panic with a string -- the custom middleware could save this to a database or report it to the user
        panic("foo")
    })

    r.GET("/", func(c *gin.Context) {
        c.String(http.StatusOK, "ohai")
    })

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

写入日志文件

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")
}

自定义日志格式

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

    // LoggerWithFormatter中间件将把日志写到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\"\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")
}

日志输出情况:

::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" "

控制日志输出颜色

默认情况下，控制台上的日志输出应根据检测到的 TTY 着色。

不需要日志颜色

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")
}

使用日志不同颜色

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")
}

模型绑定和验证

若要将请求正文绑定到类型，请使用模型绑定。我们目前支持 JSON、XML、YAML 和标准表单值（foo=bar&boo\baz）的绑定

Gin 使用 go-playground/validator/v10 进行验证.在此处查看标签使用情况的完整文档。

请注意，您需要在要绑定的所有字段上设置相应的绑定标记。例如，从 JSON 绑定时，设置。json:"fieldname"

此外，gin提供了两组绑定方法：

Type

- Must bind
- Methods - Bind, BindJSON, BindXML, BindQuery, BindYAML
- Behavior - 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 并且 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。如果您希望更好地控制绑定，考虑使用 ShouldBind 等效方法。
Type

- Should bind
- Methods - ShouldBind, ShouldBindJSON, ShouldBindXML, ShouldBindQuery, ShouldBindYAML
- Behavior - 这些方法属于 ShouldBindWith 的具体调用。如果发生绑定错误，Gin 会返回错误并由开发者处理错误和请求。使用 Bind 方法时，Gin 会尝试根据 Content-Type 推断如何绑定。如果你明确知道要绑定什么，可以使用 MustBindWith 或 ShouldBindWith。

// 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")
}

**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

使用上述的 curl 命令运行上面的示例时会返回错误。因为示例中 Password 使用了 binding:"required"。如果 Password 使用 binding:"-"，再次运行上面的示例就不会返回错误。

自定义验证器

也可以注册自定义验证器。请参阅 example code.

package main

import (
    "net/http"
    "time"

    "github.com/gin-gonic/gin"
    "github.com/gin-gonic/gin/binding"
    "github.com/go-playground/validator/v10"
)

// 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"`
}

var bookableDate validator.Func = func(fl validator.FieldLevel) bool {
    date, ok := fl.Field().Interface().(time.Time)
    if ok {
        today := time.Now()
        if today.After(date) {
            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=2030-04-16&check_out=2030-04-17"
{"message":"Booking dates are valid!"}

$ curl "localhost:8085/bookable?check_in=2030-03-10&check_out=2030-03-09"
{"error":"Key: 'Booking.CheckOut' Error:Field validation for 'CheckOut' failed on the 'gtfield' tag"}

$ curl "localhost:8085/bookable?check_in=2000-03-09&check_out=2000-03-10"
{"error":"Key: 'Booking.CheckIn' Error:Field validation for 'CheckIn' failed on the 'bookabledate' tag"}%

也可以这样注册结构级验证。有关详细信息请参阅结构-lvl 验证示例。

仅绑定查询字符串

ShouldBindQuery函数仅绑定查询参数，而不是后数据。请参阅 detail information.

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 Query String 或者 Post Data

See the detail information.

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"`
        CreateTime time.Time `form:"createTime" time_format:"unixNano"`
        UnixTime   time.Time `form:"unixTime" time_format:"unix"`
}

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)
                log.Println(person.CreateTime)
                log.Println(person.UnixTime)
        }

    c.String(200, "Success")
}

测试它：

$ curl -X GET "localhost:8085/testing?name=appleboy&address=xyz&birthday=1992-03-15&createTime=1562400033000000123&unixTime=1562400033"

绑定Uri

请参阅详细信息。

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：

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

绑定请求头

package main

import (
    "fmt"
    "github.com/gin-gonic/gin"
)

type testHeader struct {
    Rate   int    `header:"Rate"`
    Domain string `header:"Domain"`
}

func main() {
    r := gin.Default()
    r.GET("/", func(c *gin.Context) {
        h := testHeader{}

        if err := c.ShouldBindHeader(&h); err != nil {
            c.JSON(200, err)
        }

        fmt.Printf("%#v\n", h)
        c.JSON(200, gin.H{"Rate": h.Rate, "Domain": h.Domain})
    })

    r.Run()

// client
// curl -H "rate:300" -H "domain:music" 127.0.0.1:8080/
// output
// {"Domain":"music","Rate":300}
}

绑定 HTML 复选框

查看详细信息

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>

结果：

{"color":["red","green","blue"]}

Multipart/Urlencoded binding

type ProfileForm struct {
    Name   string                `form:"name" binding:"required"`
    Avatar *multipart.FileHeader `form:"avatar" binding:"required"`

    // or for multiple files
    // Avatars []*multipart.FileHeader `form:"avatar" binding:"required"`
}

func main() {
    router := gin.Default()
    router.POST("/profile", 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 ProfileForm
        // in this case proper binding will be automatically selected
        if err := c.ShouldBind(&form); err != nil {
            c.String(http.StatusBadRequest, "bad request")
            return
        }

        err := c.SaveUploadedFile(form.Avatar, form.Avatar.Filename)
        if err != nil {
            c.String(http.StatusInternalServerError, "unknown error")
            return
        }

        // db.Save(&form)

        c.String(http.StatusOK, "ok")
    })
    router.Run(":8080")
}

测试：

$ curl -X POST -v --form name=user --form "avatar=@./avatar.png" http://localhost:8080/profile

XML、JSON、YAML 和 ProtoBuf 渲染

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 防止 json 劫持。如果给定结构是数组值，则默认预结束到响应正文。"while(1),"

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，请将回调添加到响应正文。

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

    r.GET("/JSONP", func(c *gin.Context) {
        data := gin.H{
            "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")

        // client
        // curl http://127.0.0.1:8080/JSONP?callback=x
}

AsciiJSON

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

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

    r.GET("/someJSON", func(c *gin.Context) {
        data := gin.H{
            "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用它们的unicode实体替换特殊的HTML字符, e.g. < becomes \u003c.如果您想按字面意思编码这些字符 ,请使用 PureJSON 代替. 在低于go1.6的版本中不可以使用

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")
}

静态文件服务

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")
}

通过文件提供服务

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

    router.GET("/local/file", func(c *gin.Context) {
        c.File("local/file.go")
    })

    var fs http.FileSystem = // ...
    router.GET("/fs/file", func(c *gin.Context) {
        c.FileFromFS("fs/file.go", fs)
    })
}

从reader中读取数据

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
        defer reader.Close()
        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

Using LoadHTMLGlob() or 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

You can also use your own html template render

import "html/template"

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

自定义模板界定符

You may use custom delims

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

自定义模板函数

See the detail example code.

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", gin.H{
            "now": time.Date(2017, 07, 01, 0, 0, 0, 0, time.UTC),
        })
    })

    router.Run(":8080")
}

原始. tmpl

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

结果：

Date: 2017/07/01

多模板

默认情况下，gin只允许使用一个 html。模板。检查多模板渲染使用go 1.6 等功能。block template

重定向

发布 HTTP 重定向非常简单。支持内部和外部位置。

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

从 POST 发出 HTTP 重定向。请参阅问题： #444

r.POST("/test", func(c *gin.Context) {
    c.Redirect(http.StatusFound, "/foo")
})

发出路由器重定向，请如下用。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() 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")
}

中间件里有Goroutines

当在中间件或处理程序中启动新的Goroutines时, SHOULD NOT 使用原始的上下文, 你必须使用只读副本。

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 配置文件

Use directly, like this: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

example for 1-line LetsEncrypt HTTPS servers.

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 manager 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

See the question and try the following example:

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 {
        err := server01.ListenAndServe()
        if err != nil && err != http.ErrServerClosed {
            log.Fatal(err)
        }
        return err
    })

    g.Go(func() error {
        err := server02.ListenAndServe()
        if err != nil && err != http.ErrServerClosed {
            log.Fatal(err)
        }
        return err
    })

    if err := g.Wait(); err != nil {
        log.Fatal(err)
    }
}

正常关闭或重新启动

有几种方法可用于执行正常关机或重新启动。您可以使用专门为该第三方包构建的第三方包，也可以手动使用内置包中的函数和方法执行相同的操作。

第三方软件包

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

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

选择：

manners: 优雅地关闭的Go HTTP服务器
graceful: 优雅是一个Go包，它支持优雅地关闭http。服务器处理程序。
grace: 优雅的重启&零停机部署的Go服务器。

手动

如果使用 Go 1.8 或更旧版本，则可能不需要使用这些库。请考虑使用http.Server's built-in Shutdown() 方法进行正常关机。下面的示例描述了它的用法，我们这里有更多使用 gin的示例。http.Server

// +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,
    }

    // Initializing the server in a goroutine so that
    // it won't block the graceful shutdown handling below
    go func() {
        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)
    // 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("Shutting down server...")

    // The context is used to inform the server it has 5 seconds to finish
    // the request it is currently handling
    ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
    defer cancel()
    if err := srv.Shutdown(ctx); err != nil {
        log.Fatal("Server forced to shutdown:", err)
    }
    
    log.Println("Server exiting")
}

使用模板构建单个二进制文件

You can build a server into a single binary containing templates by using go-assets.

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 {
        defer file.Close()
        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

绑定 form-data request with custom struct

The follow example using custom struct:

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()
}

通过curl测试

$ 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"}}

尝试将Body绑定到不同的结构中

绑定请求正文的正常方法使用，不能多次调用它们。c.Request.Body

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，你可以使用 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在绑定之前将正文存储到上下文中。这会对性能产生轻微影响，因此，如果足以立即调用绑定，则不应使用此方法。
此功能仅适用于某些格式和-- , , , .对于其他格式，，、、、可以多次调用，而不会对性能造成任何损害（请参阅#1341 ）。JSON``XML``MsgPack``ProtoBuf``Query``Form``FormPost``FormMultipart``c.ShouldBind()

http2 服务器推送

http.Pusher 仅支持go1.8+。有关详细信息，请参阅 golang博客。

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")
}

为路由日志定义格式

路由的默认日志为：

[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)

如果要以给定格式记录此信息（例如 JSON、键值或其他内容），可以使用定义此格式。在下面的示例中，我们使用标准日志包记录所有路由，但您可以使用其他符合您需求的日志工具。gin.DebugPrintRouteFunc

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

该包是 HTTP 测试的更可取的方式。net/http/httptest

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")
}

测试上述代码示例：

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())
}