go http client, http server

Posted 2020-10-16 翔云

Go语言中的HTTP client， server非常简单。具体如下。

HTTP Server

package  main

import (
        "fmt"
        "html"
        "io/ioutil"
        "log"
        "net/http"

)


func main() {

        http.HandleFunc("/bar", func (w http.ResponseWriter, r *http.Request){
                fmt.Fprintf(w, "Hello, %q", html.EscapeString(r.URL.Path))

                if r.Method == "POST" {
                        b, err := ioutil.ReadAll(r.Body)
                        if err != nil {
                                log.Println("Read failed:", err)
                        }
                        defer r.Body.Close()


                        log.Println("b:", string(b))
                } else {

                        log.Println("ONly support Post")
                        w.Write([]byte("Only support post"))
                }

        })

        log.Fatal(http.ListenAndServe(":8080", nil))

}

HTTP Client

1. GET方式

   package main
   
   import (
           "io/ioutil"
           "log"
           "net/http"
   
   )
   
   
   func main() {
   
           url := "http://127.0.0.1:8080/bar"
   
           resp, err := http.Get(url)
           if err != nil {
                   log.Println("Get failed:", err)
                   return
           }
   
           defer resp.Body.Close()
   
           if resp.StatusCode != http.StatusOK {
                   log.Println("statuscode:", resp.StatusCode)
   
           }
   
           content, err := ioutil.ReadAll(resp.Body)
           if err != nil {
                   log.Println("Read failed:", err)
           }
   
   
           log.Println("content:", string(content))
   
   }

2. POST方式

   package main
   
   import (
           "bytes"
           "io/ioutil"
           "log"
           "net/http"
   
   )
   
   
   func main() {
   
           url := "http://127.0.0.1:8080/bar"
           contentType := "application/json;charset=utf-8"
   
           b := []byte("Hello, Server")
           body := bytes.NewBuffer(b)
   
           resp, err := http.Post(url, contentType, body)
           if err != nil {
                   log.Println("Post failed:", err)
                   return
           }
   
           defer resp.Body.Close()
   
   
           content, err := ioutil.ReadAll(resp.Body)
           if err != nil {
                   log.Println("Read failed:", err)
                   return
           }
   
   
           log.Println("content:", string(content))
   
   }
   

注意：
response的Body使用后记得close，即：

resp.Body.Close()

关于如何传递json格式数据，可以参考博文go http 传递json数据