golang-gin框架使用1

野性酷女 2024-02-22 09:09 33阅读 0赞

#### 文章目录 ####

*  一、处理请求，响应
 *   *  main.go
 *  二、模块化开发和中间件定义&使用
 *   *  main.go

## 一、处理请求，响应 ##

**包含不同请求类型的处理，response返回类型，类型绑定，和html模板和静态文件处理。**

<table> 
 <thead> 
  <tr> 
   <th>Request</th> 
   <th>Response</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td>curl -L ‘http://localhost:8080/ping?name=xwp’</td> 
   <td></td> 
  </tr> 
  <tr> 
   <td>curl -L --header ‘Content-Type: application/x-www-form-urlencoded’ --data-urlencode ‘usern=xwp’ --data-urlencode ‘password=xwp123’ http://localhost:8080/login</td> 
   <td></td> 
  </tr> 
  <tr> 
   <td>curl -L --request DELETE ‘http://localhost:8080/user/3’</td> 
   <td></td> 
  </tr> 
  <tr> 
   <td>curl -L ‘http://localhost:8080/hello?id=27&amp;username=xwp’</td> 
   <td></td> 
  </tr> 
  <tr> 
   <td>curl -L ‘http://localhost:8080/register’ --header ‘Content-Type: application/x-www-form-urlencoded’ --data-urlencode ‘name=xwp’ --data-urlencode ‘password=xwp123’ --data-urlencode ‘phone=8772463’</td> 
   <td></td> 
  </tr> 
  <tr> 
   <td>curl -L ‘http://localhost:8080/addstudent’ --header ‘Content-Type: application/json’ --data ‘{“id”: 100,“username”: “yjj”}’</td> 
   <td></td> 
  </tr> 
  <tr> 
   <td>curl -L http://localhost:8080/jsonstruct</td> 
   <td></td> 
  </tr> 
  <tr> 
   <td>http://localhost:8080/testhtml</td> 
   <td></td> 
  </tr> 
 </tbody> 
</table>

### main.go ###

package main
    
    import (
    	"fmt"
    	"log"
    	"net/http"
    
    	"github.com/gin-gonic/gin"
    )
    
    func main() {
        
    	engine := gin.Default()
    	// curl -L 'http://localhost:8080/ping?name=xwp'
    	engine.GET("/ping", func(c *gin.Context) {
        
    		// c.Writer.Write([]byte("Hello, gin!\n"))
    		query_res := c.DefaultQuery("name", "unknow")
    
    		fmt.Printf("query_res: %v\n", query_res)
    		c.JSON(http.StatusOK, gin.H{
        
    			"message":  "pong",
    			"fullPath": c.FullPath(),
    		})
    	})
    	// curl -L --header 'Content-Type: application/x-www-form-urlencoded' --data-urlencode 'usern=xwp' --data-urlencode 'password=xwp123' http://localhost:8080/login
    	engine.POST("/login", func(c *gin.Context) {
        
    		var user, password string
    		user, b := c.GetPostForm("user")
    		if !b {
        
    			c.Writer.Write([]byte("username is empty, please try again!\n"))
    			return
    		}
    		password = c.PostForm("password")
    		fmt.Printf("username: %v password: %v\n", user, password)
    		c.Writer.Write([]byte(fmt.Sprintf("%v login successfully!", user)))
    	})
    	// curl -L --request DELETE 'http://localhost:8080/user/3'
    	engine.DELETE("/user/:id", func(c *gin.Context) {
        
    		id := c.Param("id")
    		fmt.Printf("User id: %v\n", id)
    		c.JSON(http.StatusOK, gin.H{
        
    			"message": fmt.Sprintf("user %v has been deleted", id),
    		})
    	})
    	// GET提交表单：curl -L 'http://localhost:8080/hello?id=27&username=xwp'
    	engine.GET("/hello", func(c *gin.Context) {
        
    		var s Student
    		if err := c.ShouldBindQuery(&s); err != nil {
        
    			log.Fatal(err)
    			return
    		}
    		fmt.Printf("Id: %v\n", s.Id)
    		fmt.Printf("Username: %v\n", s.Username)
    		c.Writer.Write([]byte(fmt.Sprintf("hello %v\n", s.Username)))
    	})
    	// POST提交表单: curl -L 'http://localhost:8080/register' --header 'Content-Type: application/x-www-form-urlencoded' --data-urlencode 'name=xwp' --data-urlencode 'password=xwp123' --data-urlencode 'phone=8772463'
    	engine.POST("/register", func(c *gin.Context) {
        
    		var register Register
    		if err := c.ShouldBind(&register); err != nil {
        
    			log.Fatal(err)
    			return
    		}
    		fmt.Printf("Name: %v\n", register.Name)
    		fmt.Printf("Password: %v\n", register.Password)
    		fmt.Printf("Phone: %v\n", register.Phone)
    		c.Writer.Write([]byte(register.Name + " registe successfully!"))
    	})
    	// POST提交json数据表单: curl -L 'http://localhost:8080/addstudent' --header 'Content-Type: application/json' --data '{"id": 100,"username": "yjj"}'
    	engine.POST("/addstudent", func(c *gin.Context) {
        
    		var student Student
    		if err := c.BindJSON(&student); err != nil {
        
    			log.Fatal(err)
    			return
    		}
    		fmt.Printf("student.Id: %v\n", student.Id)
    		c.Writer.Write([]byte(fmt.Sprintf("%v add successfully!\n", student.Username)))
    	})
    	// resopnse以json格式返回一个结构体对象  curl -L http://localhost:8080/jsonstruct
    	engine.GET("/jsonstruct", func(c *gin.Context) {
        
    		stu1 := Student{
        Id: 5378, Username: "Lenyu"}
    		c.JSON(http.StatusOK, &stu1)
    	})
    	// 返回一个html  curl -L http://localhost:8080/testhtml
    	engine.LoadHTMLGlob("./html/*")
    	engine.Static("static", "static")
    	engine.GET("testhtml", func(c *gin.Context) {
        
    		fullPath := c.FullPath()
    		c.HTML(http.StatusOK, "index.html", gin.H{
        
    			"fullPath": fullPath,
    			"title":    "gin教程",
    		})
    	})
    	engine.Run() // listen and serve on 0.0.0.0:8080 (for windows "localhost:8080")
    }
    
    type Student struct {
        
    	Id       int    `form:"id"`
    	Username string `form:"username"`
    }
    type Register struct {
        
    	Name     string `form:"name"`
    	Phone    string `form:"phone"`
    	Password string `form:"password"`
    }

## 二、模块化开发和中间件定义&使用 ##

定义RouterGroup，定义中间件FullPathAndMethod()，打印请求路径和请求方法并返回响应状态码。

### main.go ###

package main
    
    import (
    	"fmt"
    
    	"github.com/gin-gonic/gin"
    )
    
    func main() {
        
    	// 模块化开发
    	// 用户注册： /user/register
    	// 用户登录： /user/login
    	// 用户信息： /user/info
    	// 用户删除： /user/id
    	engine := gin.Default()
    
    	rg := engine.Group("/user")
    	rg.POST("/register", FullPathAndMethod(), registerHandler)
    	rg.POST("/login", loginHandler)
    	rg.DELETE("/:id", FullPathAndMethod(), deleteHandler)
    	rg.GET("/info", FullPathAndMethod(), infoHandler)
    	engine.Run()
    }
    func registerHandler(c *gin.Context) {
        
    	fullPath := c.FullPath()
    	if _, err := c.Writer.WriteString("FullPath: " + fullPath); err != nil {
        
    		fmt.Printf("Write err: %v", err)
    		return
    	}
    	fmt.Println("registerHandler handler")
    }
    func loginHandler(c *gin.Context) {
        
    	fullPath := c.FullPath()
    	if _, err := c.Writer.WriteString("FullPath: " + fullPath); err != nil {
        
    		fmt.Printf("Write err: %v", err)
    		return
    	}
    }
    func deleteHandler(c *gin.Context) {
        
    	fullPath := c.FullPath()
    	id := c.Param("id")
    	if _, err := c.Writer.WriteString("FullPath: " + fullPath + "\nDelete user id: " + id); err != nil {
        
    		fmt.Printf("Write err: %v", err)
    		return
    	}
    }
    func infoHandler(c *gin.Context) {
        
    	fullPath := c.FullPath()
    	if _, err := c.Writer.WriteString("FullPath: " + fullPath); err != nil {
        
    		fmt.Printf("Write err: %v", err)
    		return
    	}
    }
    
    // write an middleware to print request url fullpath and request method.
    func FullPathAndMethod() gin.HandlerFunc {
        
    	return func(c *gin.Context) {
        
    		fullPath := c.FullPath()
    		method := c.Request.Method
    		fmt.Printf("fullPath: %v\n", fullPath)
    		fmt.Printf("method: %v\n", method)
    		c.Next()
    		// 打印处理响应完成后的状态码
    		httpCode := c.Writer.Status()
    		fmt.Printf("响应状态码: %v\n", httpCode)
    	}
    }