Websocket简单运用

• 是什么：全双工通信协议。
• 能做什么：服务端可以主动的发送数据给客户端
• golang应用到的包

go get github.com/gorilla/websocket

server.go

package main

import(
	"fmt"
	"log"
	"net/http"
	"github.com/gorilla/websocket"
)

// 设置合适读取字节
var upgrader = websocket.Upgrader{
	ReadBufferSize:1024,
	WriteBufferSize:1024,
	CheckOrigin:func(r *http.Request)bool{
		return true	
	}, // 解决跨域
}

func init(){
	log.SetFlags(log.Ltime|log.Lshortfile)
}

func ServerHTTP(w http.ResponseWriter,r *http.Request){
	log.Printf("客户端地址：%v",r.RemoteAddr)
	conn,err := upgrader.Upgrade(w,r,nil)
	if err!=nil{
		log.Printf("将连接升级为websocket失败：%v\n",err)
		return
	}

	// 循环不断地接收信息，和发送信息
	for{
		// 读取信息 
		messageType,p,err := conn.ReadMessage()
		if err!=nil{
			log.Printf("读取客户端发送信息失败：%v\n",err)
			return
		}
		log.Printf("客户端发送地数据类型：%d，发送地数据：%v",messageType,string(p))
		// 客户端发送数据给服务端
		if err:=conn.WriteMessage(messageType,p);err!=nil{
			log.Printf("发送数据失败：%v",err)
			return
		}
	}
}



func main(){
	fmt.Println("websocket的简单应用")
	http.HandleFunc("/ws",ServerHTTP)
	if err:=http.ListenAndServe(":8080",nil);err!=nil{
		log.Printf("打开服务有误：%v",err)
	}
}

client(angular)

 WebsocketTest(){
    if("WebSocket" in window){
      console.log("支持websocket")
    }else{
      console.warn("不支持websocket")
      return
    }
    var ws = new WebSocket("ws://localhost:8080/ws")
    ws.onopen = ()=>{
      ws.send("发送数据")
    }

    ws.onmessage = (e:any)=>{
      console.log("接收数据为",e.data)
    }

    ws.onclose =  ()=>{
      console.log("连接关闭")
    }
  }