WebSocket并发发送/接收：Go语言中的线程安全性

package main

import (
    "fmt"
    "net/http"
    "time"

    "golang.org/x/net/websocket"
)

const queueSize = 20

type Input struct {
    Cmd string `json:"cmd"`
}

type Output struct {
    Cmd string `json:"cmd"`
}

func Handler(ws *websocket.Conn) {
    msgWrite := make(chan *Output, queueSize)
    var in Input

    go writeHandler(ws, msgWrite)

    for {
        err := websocket.JSON.Receive(ws, &in)
        if err != nil {
            fmt.Println("Receive error:", err)
            break
        } else {
            msgWrite <- &Output{Cmd: "Thanks for your message: " + in.Cmd}
        }
    }
}

func writeHandler(ws *websocket.Conn, out chan *Output) {
    for {
        select {
        case d := <-out:
            err := websocket.JSON.Send(ws, &d)
            if err != nil {
                fmt.Println("Send error:", err)
                return // 退出goroutine，避免死循环
            } else {
                fmt.Println("> ", d.Cmd)
            }
        }
    }
}

func main() {
    http.Handle("/echo", websocket.Handler(Handler))
    fmt.Println("Server running on :1235")
    err := http.ListenAndServe(":1235", nil)
    if err != nil {
        panic("ListenAndServe: " + err.Error())
    }
}