http 使用小结

做一个简单的通过http协议 server 和 client 交互样例。吧内帖子很多，但是没有一个完整的样例，在这里做一个摸索总结，希望对后来的学习go语言的小伙伴有帮助。

server端代码：

package main

import (
    "fmt"
    "net/http"
)

func main()  {

    fmt.Println("server listening:")

    http.HandleFunc("/con",conncet)
    http.ListenAndServe(":8080",nil)

}

 func conncet(w http.ResponseWriter, r *http.Request) {

     r.ParseForm()

     data := r.URL.Query()
     fmt.Println("all data", data)


         var NameExist, IdExist bool
     var Id,Name []string

     if Id, NameExist = r.Form["Id"]; NameExist{
         fmt.Println("Id is ",Id[0])
     }

     if Name, IdExist = r.Form["Name"]; IdExist{
         fmt.Println("Name is ",Name[0])
     }
     if NameExist && IdExist{
          w.Write([]byte(fmt.Sprintf("welcome %s to come in",Name[0])))
     }

}

说明： server通过监听本地的8080端口，等待客户端的连接。先启动server，打印如下:

C:/Go\bin\go.exe run E:/go_code/gopath/src/example/http/httpserver.go
server listening:
all data map[Id:[321] Name:[agent]]
Id is  321
Name is  agent
all data map[Name:[agent] Id:[321]]
Id is  321
Name is  agent

client 代码，client 通过读取配置文件，获取服务的ip地址以及访问的目录地址。

package main

import (
    "fmt"
    "net/http"
    "io/ioutil"
    "encoding/json"
    //"net/url"
)

type ServerInfo struct {
    Ip   string
    Port string
    Dir  string
}
type ClientInfo struct {
    Name string
    ID string
}

type ConfigData struct {
     ServerData ServerInfo
     ClientData ClientInfo
}

func main()  {

    fmt.Println("client con:")
    client := &http.Client{}

    serveInst, clientInst, err := conInst.ServerData.GetServerInfoFromConf()
    if err != nil{
        fmt.Println(err)
        return
    }

    url := serveInst.constructUrl()
    urlpara := clientInst.constructUrl(&url)

    req, e := http.NewRequest("Get",urlpara, nil)
    if e !=nil{
        fmt.Println(e)
    }

    //v := req.Form
    //v.Set("Name",clientInst.Name)
    //v.Set("Id",clientInst.ID)

    rsp ,err1 := client.Do(req)
    if err1 != nil{
        fmt.Println("client Get err.",err1)
        return
    }

    defer  rsp.Body.Close()
    data, err2 := ioutil.ReadAll(rsp.Body)
    if err2 == nil {
        fmt.Println(string(data))
    }

    fmt.Println("client over", err2)

}

var conInst = NewConfInfo()

func NewConfInfo() *ConfigData{
    return &ConfigData{}
}


func (s *ServerInfo)GetServerInfoFromConf() (*ServerInfo, *ClientInfo,error){
    conf := &ConfigData{}
    data, err := ioutil.ReadFile("conf/info.json")
    if err != nil{
        fmt.Println("readdir failed, err is ",err)
        return nil,nil,err
    }

    err1 := json.Unmarshal(data,conf)
    if err1 != nil {
        fmt.Println("unmarshal failed, err is ",err1)
        return nil, nil,err1
    }

    fmt.Println("Get info is ",conf)
    return &conf.ServerData, &conf.ClientData,nil

}

func (s *ServerInfo)constructUrl() string {

    url := "http://" + s.Ip + ":" + s.Port + "/" + s.Dir

    fmt.Println("url is",url)
    return url
}

func (s *ClientInfo)constructUrl(url *string) string {

    //*url =*url + "?" + "Name" + "=" + s.Name
    *url =*url + "?" + "Name" + "=" + s.Name + "&"+ "Id" + "=" + s.ID

    fmt.Println("url is", *url)
    return *url
}

clinet 打印如下：

C:/Go\bin\go.exe run E:/go_code/gopath/src/example/http/httpclient.go
client con:
Get info is  &{{127.0.0.1 8080 con} {agent 321}}
url is http://127.0.0.1:8080/con
url is http://127.0.0.1:8080/con?Name=agent&Id=321
welcome agent to come in
client over <nil>

Process finished with exit code 0

json文件如下：

{
  "ServerData" :{
    "Ip" :  "127.0.0.1",
    "Port": "8080",
    "Dir" : "con"
  },
  "ClientData" :{
    "Name": "agent",
    "ID":    "321"
  }
}