Go-gin学习文档

安装gin

• 参考

  https://gin-gonic.com/docs/quickstart/

• 设置环境变量

  export GOPATH=~/golang
  export PATH=$PATH:$GOPATH/bin
  # or by vim ~/.bashrc or by ~/.zshrc

• gin

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

快速开始

• 创建文件

  // example.go
  package main
  
  import(
      "github.com/gin-gonic/gin"
  )
  
  func main(){
      r := gin.Default()
      r.GET("/", func(c *gin.Context){
          c.JSON(200, gin.H{
              "msg": "pong",
          })
      })
      r.Run()
  }

• 运行文件

  $ go run main.go
  [GIN-debug] [WARNING] Creating an Engine instance with the Logger and Recovery middleware already attached.
  
  [GIN-debug] [WARNING] Running in "debug" mode. Switch to "release" mode in production.
   - using env:   export GIN_MODE=release
   - using code:  gin.SetMode(gin.ReleaseMode)
  
  [GIN-debug] GET    /                         --> main.main.func1 (3 handlers)
  [GIN-debug] [WARNING] You trusted all proxies, this is NOT safe. We recommend you to set a value.
  Please check https://pkg.go.dev/github.com/gin-gonic/gin#readme-don-t-trust-all-proxies for details.
  [GIN-debug] Environment variable PORT is undefined. Using port :8080 by default
  [GIN-debug] Listening and serving HTTP on :8080
  

路由

• 无参数

  r.GET("/hello", func(c *gin.Context){
      c.String(200, "hello")
  })

  $ curl http://127.0.0.1:8080/hello
  hello %

• 动态路由

  r.GET("/hello/:name", func(c *gin.Context){
      name := c.Param("name")
      c.String(200, name)
  })

  $ curl http://127.0.0.1:8080/hello/golang
  golang

• 带Query参数

  //     hello?name=xxx&age=xxx
  r.GET("/hello", func(c *gin.Context){
      name := c.Query("name")
      age := c.DefaultQuery("age", "18") // 不存在取右边的默认值
      c.String(200, "%s: %s", name, age)
  })

  $ curl http://127.0.0.1:8080/hello?name=golang
  golang: 18

• 获取POST参数

  r.POST("/hello", func(c *gin.Context){
      name := c.PostForm("name")
      age := c.DefaultPostForm("age", "18")
      c.JSON(200, gin.H{
          "name": name,
          "age": age,
      })
  })

  $ curl http://127.0.0.1:8080/hello -X POST -d 'name=golang&age=26'
  {"age":"26","name":"golang"}

• Map参数(字典参数)

  r.POST("/hello", func(c *gin.Context){
      ages := c.QueryMap("ages")
      names := c.PostFormMap("names")
      c.JSON(200, gin.H{
          "name": names,
          "age": ages,
      })
  })

  $ curl -g "http://localhost:8080/hello?ages[a]=18&ages[b]=26" -X POST -d 'names[a]=Sam&names[b]=David'
  {"age":{"a":"18","b":"26"},"name":{"a":"Sam","b":"David"}}

• 重定向(Redirect)

  r.GET("/goIndex", func(c *gin.Context){
      c.Request.URL.Path = "/"
      r.HandleContext(c)
  })

  $ curl http://127.0.0.1:8080/goIndex
  {"msg":"pong"}

• 分组路由(Grouping Routes)

      defaultHandler := func(c *gin.Context) {
          c.JSON(200, gin.H{
              "path": c.FullPath(),
          })
      }
      // group: v1
      v1 := r.Group("/v1")
      {
          v1.GET("/name1", defaultHandler)
          v1.GET("/name2", defaultHandler)
      }
      // group: v2
      v2 := r.Group("/v2")
      {
          v2.GET("/name1", defaultHandler)
          v2.GET("/name2", defaultHandler)
      }

  $ curl http://127.0.0.1:8080/v1/name1
  {"path":"/v1/name1"}                                    
  $ curl http://127.0.0.1:8080/v1/name2
  {"path":"/v1/name2"}                                         
  $ curl http://127.0.0.1:8080/v2/name1
  {"path":"/v2/name1"}                                         
  $ curl http://127.0.0.1:8080/v2/name2
  {"path":"/v2/name2"}