websocket demo

README.md

How to Run

go run server.go

and in another terminal

go run client.go

client.go

package main

import (
    "log"
    "net/url"
    "time"
    "github.com/gorilla/websocket"
)

func main() {
    u := url.URL{Scheme: "wss", Host: "localhost:8080", Path: "/echo"}
    log.Printf("connecting to %s", u.String())

    c, _, err := websocket.DefaultDialer.Dial(u.String(), nil)
    if err != nil {
        log.Fatal("dial:", err)
    }
    defer c.Close()

    go func() {
        for {
            _, message, err := c.ReadMessage()
            if err != nil {
                log.Println("read:", err)
                return
            }
            log.Printf("recv: %s", message)
        }
    }()

    time.Sleep(100 * time.Second)
}

server.go

package main

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

var upgrader = websocket.Upgrader{} // use default options
var messageChan = make(chan string)


func updateMsg() {
    for {
        time.Sleep(5 * time.Second)
        messageChan <- time.Now().Format("2006-01-02 03:04:05 PM")
    }
}

func echo(w http.ResponseWriter, r *http.Request) {
    c, err := upgrader.Upgrade(w, r, nil)
    if err != nil {
        log.Print("upgrade:", err)
        return
    }
    defer c.Close()

    for {
        c.WriteMessage(websocket.TextMessage, []byte(<- messageChan))        
    }
}



func main() {
    go updateMsg()
    http.HandleFunc("/echo", echo)
    log.Fatal(http.ListenAndServe("localhost:8080", nil))
}

2020/12/16 20:34:09 dial:tls: first record does not look like a TLS handshake
exit status 1

c, _, err := websocket.DefaultDialer.Dial(u.String(), nil)的返回值是nil
https://localhost:8080/echo 不OK啊~