Go语言WebSocket服务器：解决403 Origin校验错误与灵活配置

package main

import (
    "fmt"
    "code.google.com/p/go.net/websocket"
    "net/http"
)

// webHandler 处理WebSocket连接，接收并打印消息，然后回传
func webHandler(ws *websocket.Conn) {
    var s string
    // 从WebSocket连接读取数据
    if _, err := fmt.Fscan(ws, &s); err != nil {
        fmt.Printf("Error reading from websocket: %v\n", err)
        return
    }
    fmt.Println("Received: ", s)
    // 将消息回传给客户端
    if _, err := fmt.Fprint(ws, "Echo: "+s); err != nil {
        fmt.Printf("Error writing to websocket: %v\n", err)
    }
}

func main() {
    fmt.Println("Starting WebSocket server on :8080")

    // 使用websocket.Handler注册WebSocket处理函数
    // 默认情况下，websocket.Handler会执行Origin头部校验
    http.Handle("/echo", websocket.Handler(webHandler))

    // 启动HTTP服务器监听
    err := http.ListenAndServe(":8080", nil)
    if err != nil {
        panic("ListenAndServe: " + err.Error())
    }
}

// 创建WebSocket连接
ws = new WebSocket("ws://localhost:8080/echo");

// 连接成功时触发
ws.onopen = function(event) {
    console.log("WebSocket connection opened.");
    // 连接建立后发送一条消息
    ws.send("Hello from client!");
};

// 收到服务器消息时触发
ws.onmessage = function(e) {
    console.log("WebSocket message received: " + e.data);
};

// 连接发生错误时触发
ws.onerror = function(error) {
    console.error("WebSocket error: ", error);
};

// 连接关闭时触发
ws.onclose = function(event) {
    console.log("WebSocket connection closed:", event.code, event.reason);
};

package main

import (
    "fmt"
    "code.google.com/p/go.net/websocket"
    "net/http"
)

// webHandler 保持不变，处理WebSocket连接的业务逻辑
func webHandler(ws *websocket.Conn) {
    var s string
    if _, err := fmt.Fscan(ws, &s); err != nil {
        fmt.Printf("Error reading from websocket: %v\n", err)
        return
    }
    fmt.Println("Received: ", s)
    // 示例：回传消息
    if _, err := fmt.Fprint(ws, "Echo: "+s); err != nil {
        fmt.Printf("Error writing to websocket: %v\n", err)
    }
}

func main() {
    fmt.Println("Starting WebSocket server on :8080 with custom Origin handling")

    // 使用http.HandleFunc注册一个普通的HTTP处理函数
    // 在这个处理函数内部，我们创建并使用websocket.Server实例
    http.HandleFunc("/echo",
        func (w http.ResponseWriter, req *http.Request) {
            // 创建websocket.Server实例
            // 将webHandler作为其Handler。
            // 关键点：当websocket.Server的Handshake字段为nil时，它不会执行Origin校验，
            // 而是接受所有连接。这与websocket.Handler的默认行为不同。
            s := websocket.Server{Handler: websocket.Handler(webHandler)}
            // 调用ServeHTTP来处理当前的HTTP请求，将其升级为WebSocket连接
            s.ServeHTTP(w, req)
        })

    err := http.ListenAndServe(":8080", nil)
    if err != nil {
        panic("ListenAndServe: " + err.Error())
    }
}