【Golang】2021 Gin Web 框架中文文档

我不是女神ヾ 2022-11-10 00:53 930阅读 0赞

# 写在前面 #

昨天要看了一下Gin这个框架，在GitHub上面看文档，奈何英文不好，看着好难受，虽说有插件可以划词翻译，不过要不断划词翻译，比较麻烦，索性直接把他翻译成中文，方便查看，虽说，看文档也主要是看示例代码怎么用，但是有中文辅助来看，速度会更快一些。

[源项目链接][Link 1]  
[Gin Web框架文档原文][Gin Web]  
[译者：攻城狮白玉的博客][Link 2]

翻译的不好的地方请提出修改意见哦

# Gin Web 框架 #

![color.png][]

Gin是用Go(Golang)编写的Web框架。 它具有类似于martini的API，其性能最高可提高40倍。 [httprouter][]. 如果您需要性能和良好的生产率，您会爱上Gin的。

## Contents ##

*  Gin Web 框架
    
     *  内容
     *  安装
     *  快速开始
     *  Benchmarks
     *  Gin v1. stable
     *  Build with jsoniter
     *  API Examples
        
         *  Using GET, POST, PUT, PATCH, DELETE and OPTIONS
         *  路径中的参数
         *  查询字符串参数
         *  多部分/ Ullencoded形式
         *  另一个示例：查询+帖子形式
         *  映射为查询字符串或后格式参数
         *  上传文件
            
             *  单个文件
             *  多个文件
         *  分组路线
         *  默认情况下没有中间件的空白Gin
         *  使用中间件
         *  如何写入日志文件
         *  自定义日志格式
         *  控制日志输出颜色
         *  模型绑定和验证
         *  自定义验证程序
         *  仅绑定查询字符串
         *  绑定查询字符串或发布数据
         *  Bind Uri
         *  绑定标题
         *  绑定HTML复选框
         *  多部分/ Urlencoded绑定
         *  XML，JSON，YAML和ProtoBuf渲染
            
             *  SecureJSON
             *  JSONP
             *  AsciiJSON
             *  PureJSON
         *  提供静态文件
         *  从文件提供数据
         *  从阅读器提供数据
         *  HTML渲染
            
             *  自定义模板渲染器
             *  自定义分隔符
             *  自定义模板功能
         *  Multitemplate
         *  重定向
         *  自定义中间件
         *  使用BasicAuth()中间件
         *  中间件内部的Goroutines
         *  自定义HTTP配置
         *  支持加密
         *  使用Gin运行多种服务
         *  正常关闭或重新启动
            
             *  第三方软件包
             *  手动
         *  使用模板构建单个二进制文件
         *  使用自定义结构绑定表单数据请求
         *  尝试将主体绑定到不同的结构中
         *  http2服务器推送
         *  定义路径日志的格式
         *  设置并获取Cookie
     *  测试
     *  用户

## 安装 ##

要安装Gin软件包，您需要安装Go并首先设置Go工作区。

1.  首先需要安装[Go][](**需要1.12+版本**)，然后可以使用下面的Go命令安装Gin。

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

1.  将其导入您的代码中：

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

1.  (可选)导入`net / http`。 例如，在使用诸如“ http.StatusOK”之类的常量时，这是必需的。

import "net/http"

## 快速开始 ##

# 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

## Benchmarks ##

Gin 使用[HttpRouter][httprouter]的自定义版本

\[查看所有基准\](/ BENCHMARKS.md)

<table> 
 <thead> 
  <tr> 
   <th>Benchmark name</th> 
   <th align="right">(1)</th> 
   <th align="right">(2)</th> 
   <th align="right">(3)</th> 
   <th align="right">(4)</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td>BenchmarkGin_GithubAll</td> 
   <td align="right"><strong>43550</strong></td> 
   <td align="right"><strong>27364 ns/op</strong></td> 
   <td align="right"><strong>0 B/op</strong></td> 
   <td align="right"><strong>0 allocs/op</strong></td> 
  </tr> 
  <tr> 
   <td>BenchmarkAce_GithubAll</td> 
   <td align="right">40543</td> 
   <td align="right">29670 ns/op</td> 
   <td align="right">0 B/op</td> 
   <td align="right">0 allocs/op</td> 
  </tr> 
  <tr> 
   <td>BenchmarkAero_GithubAll</td> 
   <td align="right">57632</td> 
   <td align="right">20648 ns/op</td> 
   <td align="right">0 B/op</td> 
   <td align="right">0 allocs/op</td> 
  </tr> 
  <tr> 
   <td>BenchmarkBear_GithubAll</td> 
   <td align="right">9234</td> 
   <td align="right">216179 ns/op</td> 
   <td align="right">86448 B/op</td> 
   <td align="right">943 allocs/op</td> 
  </tr> 
  <tr> 
   <td>BenchmarkBeego_GithubAll</td> 
   <td align="right">7407</td> 
   <td align="right">243496 ns/op</td> 
   <td align="right">71456 B/op</td> 
   <td align="right">609 allocs/op</td> 
  </tr> 
  <tr> 
   <td>BenchmarkBone_GithubAll</td> 
   <td align="right">420</td> 
   <td align="right">2922835 ns/op</td> 
   <td align="right">720160 B/op</td> 
   <td align="right">8620 allocs/op</td> 
  </tr> 
  <tr> 
   <td>BenchmarkChi_GithubAll</td> 
   <td align="right">7620</td> 
   <td align="right">238331 ns/op</td> 
   <td align="right">87696 B/op</td> 
   <td align="right">609 allocs/op</td> 
  </tr> 
  <tr> 
   <td>BenchmarkDenco_GithubAll</td> 
   <td align="right">18355</td> 
   <td align="right">64494 ns/op</td> 
   <td align="right">20224 B/op</td> 
   <td align="right">167 allocs/op</td> 
  </tr> 
  <tr> 
   <td>BenchmarkEcho_GithubAll</td> 
   <td align="right">31251</td> 
   <td align="right">38479 ns/op</td> 
   <td align="right">0 B/op</td> 
   <td align="right">0 allocs/op</td> 
  </tr> 
  <tr> 
   <td>BenchmarkGocraftWeb_GithubAll</td> 
   <td align="right">4117</td> 
   <td align="right">300062 ns/op</td> 
   <td align="right">131656 B/op</td> 
   <td align="right">1686 allocs/op</td> 
  </tr> 
  <tr> 
   <td>BenchmarkGoji_GithubAll</td> 
   <td align="right">3274</td> 
   <td align="right">416158 ns/op</td> 
   <td align="right">56112 B/op</td> 
   <td align="right">334 allocs/op</td> 
  </tr> 
  <tr> 
   <td>BenchmarkGojiv2_GithubAll</td> 
   <td align="right">1402</td> 
   <td align="right">870518 ns/op</td> 
   <td align="right">352720 B/op</td> 
   <td align="right">4321 allocs/op</td> 
  </tr> 
  <tr> 
   <td>BenchmarkGoJsonRest_GithubAll</td> 
   <td align="right">2976</td> 
   <td align="right">401507 ns/op</td> 
   <td align="right">134371 B/op</td> 
   <td align="right">2737 allocs/op</td> 
  </tr> 
  <tr> 
   <td>BenchmarkGoRestful_GithubAll</td> 
   <td align="right">410</td> 
   <td align="right">2913158 ns/op</td> 
   <td align="right">910144 B/op</td> 
   <td align="right">2938 allocs/op</td> 
  </tr> 
  <tr> 
   <td>BenchmarkGorillaMux_GithubAll</td> 
   <td align="right">346</td> 
   <td align="right">3384987 ns/op</td> 
   <td align="right">251650 B/op</td> 
   <td align="right">1994 allocs/op</td> 
  </tr> 
  <tr> 
   <td>BenchmarkGowwwRouter_GithubAll</td> 
   <td align="right">10000</td> 
   <td align="right">143025 ns/op</td> 
   <td align="right">72144 B/op</td> 
   <td align="right">501 allocs/op</td> 
  </tr> 
  <tr> 
   <td>BenchmarkHttpRouter_GithubAll</td> 
   <td align="right">55938</td> 
   <td align="right">21360 ns/op</td> 
   <td align="right">0 B/op</td> 
   <td align="right">0 allocs/op</td> 
  </tr> 
  <tr> 
   <td>BenchmarkHttpTreeMux_GithubAll</td> 
   <td align="right">10000</td> 
   <td align="right">153944 ns/op</td> 
   <td align="right">65856 B/op</td> 
   <td align="right">671 allocs/op</td> 
  </tr> 
  <tr> 
   <td>BenchmarkKocha_GithubAll</td> 
   <td align="right">10000</td> 
   <td align="right">106315 ns/op</td> 
   <td align="right">23304 B/op</td> 
   <td align="right">843 allocs/op</td> 
  </tr> 
  <tr> 
   <td>BenchmarkLARS_GithubAll</td> 
   <td align="right">47779</td> 
   <td align="right">25084 ns/op</td> 
   <td align="right">0 B/op</td> 
   <td align="right">0 allocs/op</td> 
  </tr> 
  <tr> 
   <td>BenchmarkMacaron_GithubAll</td> 
   <td align="right">3266</td> 
   <td align="right">371907 ns/op</td> 
   <td align="right">149409 B/op</td> 
   <td align="right">1624 allocs/op</td> 
  </tr> 
  <tr> 
   <td>BenchmarkMartini_GithubAll</td> 
   <td align="right">331</td> 
   <td align="right">3444706 ns/op</td> 
   <td align="right">226551 B/op</td> 
   <td align="right">2325 allocs/op</td> 
  </tr> 
  <tr> 
   <td>BenchmarkPat_GithubAll</td> 
   <td align="right">273</td> 
   <td align="right">4381818 ns/op</td> 
   <td align="right">1483152 B/op</td> 
   <td align="right">26963 allocs/op</td> 
  </tr> 
  <tr> 
   <td>BenchmarkPossum_GithubAll</td> 
   <td align="right">10000</td> 
   <td align="right">164367 ns/op</td> 
   <td align="right">84448 B/op</td> 
   <td align="right">609 allocs/op</td> 
  </tr> 
  <tr> 
   <td>BenchmarkR2router_GithubAll</td> 
   <td align="right">10000</td> 
   <td align="right">160220 ns/op</td> 
   <td align="right">77328 B/op</td> 
   <td align="right">979 allocs/op</td> 
  </tr> 
  <tr> 
   <td>BenchmarkRivet_GithubAll</td> 
   <td align="right">14625</td> 
   <td align="right">82453 ns/op</td> 
   <td align="right">16272 B/op</td> 
   <td align="right">167 allocs/op</td> 
  </tr> 
  <tr> 
   <td>BenchmarkTango_GithubAll</td> 
   <td align="right">6255</td> 
   <td align="right">279611 ns/op</td> 
   <td align="right">63826 B/op</td> 
   <td align="right">1618 allocs/op</td> 
  </tr> 
  <tr> 
   <td>BenchmarkTigerTonic_GithubAll</td> 
   <td align="right">2008</td> 
   <td align="right">687874 ns/op</td> 
   <td align="right">193856 B/op</td> 
   <td align="right">4474 allocs/op</td> 
  </tr> 
  <tr> 
   <td>BenchmarkTraffic_GithubAll</td> 
   <td align="right">355</td> 
   <td align="right">3478508 ns/op</td> 
   <td align="right">820744 B/op</td> 
   <td align="right">14114 allocs/op</td> 
  </tr> 
  <tr> 
   <td>BenchmarkVulcan_GithubAll</td> 
   <td align="right">6885</td> 
   <td align="right">193333 ns/op</td> 
   <td align="right">19894 B/op</td> 
   <td align="right">609 allocs/op</td> 
  </tr> 
 </tbody> 
</table>

\-(1)：在固定时间内完成总重复次数，越高表示结果越自信  
\-(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数(分配/操作)，越低越好

## Gin v1. stable ##

*  零分配路由器。
 *  仍然是最快的http路由器和框架。 从路由到写作。
 *  完整的单元测试套件。
 *  战斗测试。
 *  API已冻结，新版本不会破坏您的代码。

## Build with [jsoniter][] ##

Gin使用`encoding / json`作为默认的json包，但是您可以通过其他标签的构建将其更改为[jsoniter][]。

$ go build -tags=jsoniter .

## API Examples ##

您可以在[Gin示例库][Gin]中找到许多现成的示例。

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

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
    }

### 路由参数 ###

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")
    }

### Another example: query + 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 作为查询字符串或者 post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

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 ####

参考问题[＃774][774]和详细信息\[示例代码\](https://github.com/gin-gonic/examples/tree/master/ 上传文件/单个)。

`file.Filename` **不应该被信任**。 参见[MDN上的Content-Disposition\`][MDN_Content-Disposition]和\[＃1693\](https：// github .com / gin-gonic / gin / issues / 1693)

> 文件名始终是可选的，并且不能被应用程序盲目使用：路径信息应被删除，并且应完成向服务器文件系统规则的转换。

func main() { 
    	router := gin.Default()
    	// Set a lower memory limit for multipart forms (default is 32 MiB)
    	router.MaxMultipartMemory = 8 << 20  // 8 MiB
    	router.POST("/upload", func(c *gin.Context) { 
    		// single file
    		file, _ := c.FormFile("file")
    		log.Println(file.Filename)
    
    		// Upload the file to specific dst.
    		c.SaveUploadedFile(file, dst)
    
    		c.String(http.StatusOK, fmt.Sprintf("'%s' uploaded!", file.Filename))
    	})
    	router.Run(":8080")
    }

How to `curl`:

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

#### 多个文件 ####

查看详细信息[示例代码][Link 3]。

func main() { 
    	router := gin.Default()
    	// Set a lower memory limit for multipart forms (default is 32 MiB)
    	router.MaxMultipartMemory = 8 << 20  // 8 MiB
    	router.POST("/upload", func(c *gin.Context) { 
    		// Multipart form
    		form, _ := c.MultipartForm()
    		files := form.File["upload[]"]
    
    		for _, file := range files { 
    			log.Println(file.Filename)
    
    			// Upload the file to specific dst.
    			c.SaveUploadedFile(file, dst)
    		}
    		c.String(http.StatusOK, fmt.Sprintf("%d files uploaded!", len(files)))
    	})
    	router.Run(":8080")
    }

How to `curl`:

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")
    }

### 默认的没有中间件的空白 Gin ###

Use

r := gin.New()

instead of

// Default With the Logger and Recovery middleware already attached
    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")
    }

### 自定义恢复行为 ###

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")
    }

### 如何写入日志文件 ###

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 middleware will write the logs to gin.DefaultWriter
    	// By default gin.DefaultWriter = os.Stdout
    	router.Use(gin.LoggerWithFormatter(func(param gin.LogFormatterParams) string { 
    
    		// your custom format
    		return fmt.Sprintf("%s - [%s] \"%s %s %s %d %s \"%s\" %s\"\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")
    }

**Sample Output**

::1 - [Fri, 07 Dec 2018 17:04:38 JST] "GET /ping HTTP/1.1 200 122.767µs "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/71.0.3578.80 Safari/537.36" "

### 控制日志输出颜色 ###

默认情况下，控制台上输出的日志应根据检测到的TTY进行着色。

永远不要为日志着色：

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")
    }

Always colorize logs:

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 ###

要将请求主体绑定为类型，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 \*\*][go-playground _ validator _ v10]进行验证。 在[这里][Link 4]上查看有关标签用法的完整文档。

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

此外，Gin提供了两种绑定方法：

*  **类型**\-必须绑定
    
     *  **方法** \- `Bind`, `BindJSON`, `BindXML`, `BindQuery`, `BindYAML`, `BindHeader`
     *  **行为** \- 这些方法在后台使用`MustBindWith`。 如果存在绑定错误，则请求将通过c.AbortWithError(400，err).SetType(ErrorTypeBind)中止。 这将响应状态代码设置为400， `Content-Type` 标头设置为`text/plain; charset=utf-8`。 请注意，如果您尝试在此之后设置响应代码，则将导致警告`[GIN-debug]。[WARNING]标头已被写入。 想要用422`。覆盖状态代码400。 如果您希望对行为有更好的控制，请考虑使用 `ShouldBind` 等效方法。
 *  **类型**\-应绑定
    
     *  **方法** \- `ShouldBind`, `ShouldBindJSON`, `ShouldBindXML`, `ShouldBindQuery`, `ShouldBindYAML`, `ShouldBindHeader`
     *  **行为** \- 这些方法在后台使用 `ShouldBindWith` 。 如果存在绑定错误，则返回错误，开发人员有责任适当处理请求和错误。

当使用Bind方法时，Gin尝试根据Content-Type标头推断出活页夹。 如果确定要绑定的内容，则可以使用`MustBindWith`或`ShouldBindWith`。

您也可以指定必填字段。 如果一个字段用`“ binding:"required"`修饰，并且绑定时值为空，则将返回错误。

// Binding from JSON
    type Login struct { 
    	User     string `form:"user" json:"user" xml:"user" binding:"required"`
    	Password string `form:"password" json:"password" xml:"password" binding:"required"`
    }
    
    func main() { 
    	router := gin.Default()
    
    	// Example for binding JSON ({"user": "manu", "password": "123"})
    	router.POST("/loginJSON", func(c *gin.Context) { 
    		var json Login
    		if err := c.ShouldBindJSON(&json); err != nil { 
    			c.JSON(http.StatusBadRequest, gin.H{ "error": err.Error()})
    			return
    		}
    
    		if json.User != "manu" || json.Password != "123" { 
    			c.JSON(http.StatusUnauthorized, gin.H{ "status": "unauthorized"})
    			return
    		}
    
    		c.JSON(http.StatusOK, gin.H{ "status": "you are logged in"})
    	})
    
    	// Example for binding XML (
    	// <?xml version="1.0" encoding="UTF-8"?>
    	// <root>
    	// <user>user</user>
    	// <password>123</password>
    	// </root>)
    	router.POST("/loginXML", func(c *gin.Context) { 
    		var xml Login
    		if err := c.ShouldBindXML(&xml); err != nil { 
    			c.JSON(http.StatusBadRequest, gin.H{ "error": err.Error()})
    			return
    		}
    
    		if xml.User != "manu" || xml.Password != "123" { 
    			c.JSON(http.StatusUnauthorized, gin.H{ "status": "unauthorized"})
    			return
    		}
    
    		c.JSON(http.StatusOK, gin.H{ "status": "you are logged in"})
    	})
    
    	// Example for binding a HTML form (user=manu&password=123)
    	router.POST("/loginForm", func(c *gin.Context) { 
    		var form Login
    		// This will infer what binder to use depending on the content-type header.
    		if err := c.ShouldBind(&form); err != nil { 
    			c.JSON(http.StatusBadRequest, gin.H{ "error": err.Error()})
    			return
    		}
    
    		if form.User != "manu" || form.Password != "123" { 
    			c.JSON(http.StatusUnauthorized, gin.H{ "status": "unauthorized"})
    			return
    		}
    
    		c.JSON(http.StatusOK, gin.H{ "status": "you are logged in"})
    	})
    
    	// Listen and serve on 0.0.0.0:8080
    	router.Run(":8080")
    }

**Sample request**

$ 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`命令运行上面的例子时，它返回错误。 因为该示例对`Password`使用`binding：“ required”`。 如果对`Password`使用`binding：“-”`，那么当再次运行以上示例时，它不会返回错误。

### 自定义验证器 ###

也可以注册自定义验证器。 参见[示例代码][Link 5]。

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"}%

[结构级别验证][Link 6]也可以通过这种方式进行注册。  
请参阅[struct-lvl-validation示例][struct-lvl-validation]以了解更多信息。

\#\#\#仅绑定查询字符串

“ ShouldBindQuery”函数仅绑定查询参数，而不绑定发布数据。 参见[详细信息][Link 7]。

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")
    }

### 绑定查询字符串或发布数据 ###

参见[详细信息][Link 8]。

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")
    }

用以下方法进行测试：

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

### 绑定Uri ###

See the [detail information][].

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")
    }

用以下方法进行测试：

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

### 绑定Header ###

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 ###

参见[详细信息][Link 9]

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 绑定 ###

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")
    }

用以下方法进行测试：

$ 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。 如果给定的结构是数组值，则默认在响应主体前添加“ 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从其他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主体。

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生成带有转义的非ASCII字符的纯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用其unicode实体替换特殊的HTML字符，例如 `<`变成`\u003c`。 如果要按字面意义编码此类字符，则可以改用PureJSON。  
此功能在Go 1.6及更低版本中不可用。

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")
    }

### 提供静态文件 ###

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")
    }

### 从文件中提取数据 ###

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 提供数据 ###

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 ###

使用LoadHTMLGlob()或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 ####

您也可以使用自己的html模板渲染

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 ####

您可以使用自定义的delims

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

#### 自定义模板函数 ####

查看详细信息[示例代码][Link 10]。

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")
    }

raw.tmpl

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

Result:

Date: 2017/07/01

### Multitemplate ###

Gin 默认情况下仅使用一个`html.Template`。 检查[多模板渲染][Link 11]是否使用了go 1.6`block template`之类的功能。

### Redirects ###

发出HTTP重定向很容易。 内部和外部位置均受支持。

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][444]

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

Issuing a Router redirect, use `HandleContext` like below.

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")
    }

### 中间件中的Goroutines ###

在中间件或处理程序中启动新的Goroutines时，您“不能”使用其中的原始上下文，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 ###

直接使用`http.ListenAndServe()`，如下所示：

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

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 ###

1行LetsEncrypt HTTPS服务器的示例。

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"))
    }

自定义自动证书管理器的示例。

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))
    }

### 使用Gin运行多种服务 ###

请参阅[问题][Link 12]并尝试以下示例：

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 ###

您可以使用几种方法来正常关闭或重新启动。 您可以使用专门为此目的构建的第三方程序包，也可以使用内置程序包中的功能和方法手动执行相同的操作。

#### 第三方软件包 ####

我们可以使用[fvbock / endless][fvbock _ endless]替换默认的`ListenAndServe`。 有关更多详细信息，请参见问题[＃296][296]。

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

备择方案：

*  [manners][]：礼貌地关闭HTTP服务器。
 *  [graceful][]：Graceful是一个Go程序包，可用于正常关闭http.Handler服务器。
 *  [grace][]：为Go服务器平稳重启和零停机部署。

#### 手动 ####

如果您使用的是Go 1.8或更高版本，则可能不需要使用这些库。 考虑使用`http.Server`内置的[Shutdown()][Shutdown]方法进行正常关闭。 下面的示例描述了它的用法，我们在\[此处\]使用gin的更多示例(https://github.com/gin-gonic/examples/tree/master/graceful-shutdown)。

// +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 && errors.Is(err, http.ErrServerClosed) { 
    			log.Printf("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 ###

您可以使用\[go-assets\] \[\]将服务器构建为包含模板的单个二进制文件。

\[go-assets\]：https://github.com/jessevdk/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
    }

请参阅https://github.com/gin-gonic/examples/tree/master/assets-in-binary目录中的完整示例。

### 将表单数据请求与自定义结构绑定 ###

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()
    }

使用命令`curl`命令结果：

$ 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"}}

### 尝试将主体绑定到不同的结构中 ###

绑定请求主体的普通方法使用了c.Request.Body，它们  
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 { 
        ...
      }
    }

为此，您可以使用`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`在绑定之前将主体存储到上下文中。 这有  
    对性能有轻微影响，因此如果您是  
    足以立即调用绑定。
 *  仅某些格式需要此功能-JSON，XML，MsgPack，  
    ProtoBuf。 对于其他格式，`Query`，`Form`，`FormPost`，`FormMultipart`，  
    可以被c.ShouldBind()多次调用，而不会损坏  
    性能(请参见[＃1341][1341])。

### http2服务器推送 ###

仅\*\* go1.8 + \*\*支持http.Pusher。 有关详细信息，请参见[golang博客][golang]。

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 ###

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(例如JSON，键值或其他格式)记录此信息，则可以使用gin.DebugPrintRouteFunc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，但是您可以使用其他适合您需求的日志工具。

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` 软件包是HTTP测试的首选方法。.

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())
    }

## 用户 ##

使用[Gin][Link 1]网络框架的出色项目列表。

*  [gorush][]：用Go编写的推送通知服务器。
 *  [fnproject][]：容器本机，与云无关的无服务器平台。
 *  [photoprism][]：由Go和Google TensorFlow支持的个人照片管理。
 *  [krakend][]：具有中间件的超高性能API网关。
 *  [picfit][]：用Go语言编写的图像调整大小服务器。
 *  [brigade][]：Kubernetes的基于事件的脚本。
 *  [dkron][]：分布式，容错的作业调度系统。

[Link 1]: https://github.com/gin-gonic/gin
[Gin Web]: https://github.com/gin-gonic/gin/blob/master/README.md
[Link 2]: https://blog.csdn.net/zhh763984017
[color.png]: https://raw.githubusercontent.com/gin-gonic/logo/master/color.png
[httprouter]: https://github.com/julienschmidt/httprouter
[Go]: https://golang.org/
[jsoniter]: https://github.com/json-iterator/go
[Gin]: https://github.com/gin-gonic/examples
[774]: https://github.com/gin-gonic/gin/issues/774
[MDN_Content-Disposition]: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Disposition#Directives
[Link 3]: https://github.com/gin-gonic/examples/tree/master/upload-file/multiple
[go-playground _ validator _ v10]: https://github.com/go-playground/validator
[Link 4]: https://godoc.org/github.com/go-playground/validator#hdr-Baked_In_Validators_and_Tags
[Link 5]: https://github.com/gin-gonic/examples/tree/master/custom-validation/server.go
[Link 6]: https://github.com/go-playground/validator/releases/tag/v8.7
[struct-lvl-validation]: https://github.com/gin-gonic/examples/tree/master/struct-lvl-validations
[Link 7]: https://github.com/gin-gonic/gin/issues/742#issuecomment-315953017
[Link 8]: https://github.com/gin-gonic/gin/issues/742#issuecomment-264681292
[detail information]: https://github.com/gin-gonic/gin/issues/846
[Link 9]: https://github.com/gin-gonic/gin/issues/129#issuecomment-124260092
[Link 10]: https://github.com/gin-gonic/examples/tree/master/template
[Link 11]: https://github.com/gin-contrib/multitemplate
[444]: https://github.com/gin-gonic/gin/issues/444
[Link 12]: https://github.com/gin-gonic/gin/issues/346
[fvbock _ endless]: https://github.com/fvbock/endless
[296]: https://github.com/gin-gonic/gin/issues/296
[manners]: https://github.com/braintree/manners
[graceful]: https://github.com/tylerb/graceful
[grace]: https://github.com/facebookgo/grace
[Shutdown]: https://golang.org/pkg/net/http/#Server.Shutdown
[1341]: https://github.com/gin-gonic/gin/pull/1341
[golang]: https://blog.golang.org/h2push
[gorush]: https://github.com/appleboy/gorush
[fnproject]: https://github.com/fnproject/fn
[photoprism]: https://github.com/photoprism/photoprism
[krakend]: https://github.com/devopsfaith/krakend
[picfit]: https://github.com/thoas/picfit
[brigade]: https://github.com/brigadecore/brigade
[dkron]: https://github.com/distribworks/dkron