PHP實(shí)現(xiàn)WebSocket實(shí)例詳解

GET /chat HTTP/1.1 
　　Host: server.example.com 
　　Upgrade: websocket //告訴服務(wù)器現(xiàn)在發(fā)送的是WebSocket協(xié)議
　　Connection: Upgrade 
　　Sec-WebSocket-Key: x3JJHMbDL1EzLkh9GBhXDw== //是一個(gè)Base64 encode的值，這個(gè)是瀏覽器隨機(jī)生成的，用于驗(yàn)證服務(wù)器端返回?cái)?shù)據(jù)是否是WebSocket助理
　　Sec-WebSocket-Protocol: chat, superchat 
　　Sec-WebSocket-Version: 13 
　　Origin: http://example.com

HTTP/1.1 101 Switching Protocols 
　 Upgrade: websocket //依然是固定的，告訴客戶端即將升級(jí)的是Websocket協(xié)議，而不是mozillasocket，lurnarsocket或者shitsocket
　 Connection: Upgrade 
　 Sec-WebSocket-Accept: HSmrc0sMlYUkAGmm5OPpG2HaGWk= //這個(gè)則是經(jīng)過(guò)服務(wù)器確認(rèn)，并且加密過(guò)后的 Sec-WebSocket-Key,也就是client要求建立WebSocket驗(yàn)證的憑證
　 Sec-WebSocket-Protocol: chat

?php

if(($socket = socket_create(AF_INET,SOCK_STREAM,SOL_TCP))  0) {
    echo "socket_create() 失敗的原因是:".socket_strerror($sock)."\n";
}
if(($ret = socket_bind($socket,'127.0.0.1','9090'))  0) {
    echo "socket_bind() 失敗的原因是:".socket_strerror($ret)."\n";
}
if(($ret = socket_listen($socket,3))  0) {
    echo "socket_listen() 失敗的原因是:".socket_strerror($ret)."\n";
}

$all_sockets = [$socket];    // socket 集合

do {
    $copy_sockets = $all_sockets;   // 單獨(dú)拷貝一份

    // 因?yàn)榭蛻舳耸情L(zhǎng)連接，如果客戶端非正常斷開，服務(wù)端會(huì)在 socket_accept 阻塞，現(xiàn)在使用 select 非阻塞模式 socket
    if(socket_select($copy_sockets, $write, $except, 0) === false)
        exit('sosket_select error!');

    // 接收第一次 socket 連入，連入后移除服務(wù)端 socket
    if(in_array($socket, $copy_sockets)) {
        $client = socket_accept($socket);
        if($client) {
            $buf = socket_read($client, 1024);
            echo $buf;

            // 匹配 Sec-Websocket-Key 標(biāo)識(shí)
            if (preg_match("/Sec-WebSocket-Key: (.*)\r\n/i",$buf,$match)) {
                // 需要將 Sec-WebSocket-Key 值累加字符串，并依次進(jìn)行 SHA-1 加密和 base64 加密
                $key = base64_encode(sha1($match[1] . '258EAFA5-E914-47DA-95CA-C5AB0DC85B11',true));
                // 拼湊響應(yīng)內(nèi)容
                $res= "HTTP/1.1 101 Switching Protocol".PHP_EOL
                    ."Upgrade: WebSocket".PHP_EOL
                    ."Connection: Upgrade".PHP_EOL
                    ."WebSocket-Location: ws://127.0.0.1:9090".PHP_EOL
                    ."Sec-WebSocket-Accept: " . $key .PHP_EOL.PHP_EOL;  // 注意這里，需要兩個(gè)換行
                // 向客戶端應(yīng)答 Sec-WebSocket-Accept
                socket_write($client, $res, strlen($res));
                // 向客戶端發(fā)送消息
                socket_write($client, buildMsg('socket ok'), 1024);

                // 加入客戶端 socket
                $all_sockets[] = $client;
            }
            // 移除服務(wù)端 socket
            $key = array_search($socket, $copy_sockets);
            unset($copy_sockets[$key]);

            // socket_close($client);
        }
    }

    // 循環(huán)所有客戶端 sockets
    foreach ($copy_sockets as $s) {
        // 獲取客戶端發(fā)給服務(wù)端的內(nèi)容
        $buf = socket_read($s, 8024);
        echo strlen($buf).'---'.PHP_EOL;
        // 代表客戶端主動(dòng)關(guān)閉
        if(strlen($buf)  9) {
            $key = array_search($s, $all_sockets);
            unset($all_sockets[$key]);
            socket_close($s);
            continue;
        }
        // 輸出
        echo getMsg($buf).PHP_EOL;
    }

}while(true);
socket_close($socket);

// 編碼服務(wù)端向客戶端發(fā)送的內(nèi)容
function buildMsg($msg) {
    $frame = [];
    $frame[0] = '81';
    $len = strlen($msg);
    if ($len  126) {
        $frame[1] = $len  16 ? '0' . dechex($len) : dechex($len);
    } else if ($len  65025) {
        $s = dechex($len);
        $frame[1] = '7e' . str_repeat('0', 4 - strlen($s)) . $s;
    } else {
        $s = dechex($len);
        $frame[1] = '7f' . str_repeat('0', 16 - strlen($s)) . $s;
    }
    $data = '';
    $l = strlen($msg);
    for ($i = 0; $i  $l; $i++) {
        $data .= dechex(ord($msg{$i}));
    }
    $frame[2] = $data;
    $data = implode('', $frame);
    return pack("H*", $data);
}

// 解析客戶端向服務(wù)端發(fā)送的內(nèi)容
function getMsg($buffer) {
    $res = '';
    $len = ord($buffer[1])  127;
    if ($len === 126) {
        $masks = substr($buffer, 4, 4);
        $data = substr($buffer, 8);
    } else if ($len === 127) {
        $masks = substr($buffer, 10, 4);
        $data = substr($buffer, 14);
    } else {
        $masks = substr($buffer, 2, 4);
        $data = substr($buffer, 6);
    }
    for ($index = 0; $index  strlen($data); $index++) {
        $res .= $data[$index] ^ $masks[$index % 4];
    }
    return $res;
}

!DOCTYPE html>
html lang="en">
head>
    meta charset="UTF-8">
    title>Title/title>
    script>
        // 創(chuàng)建一個(gè)Socket實(shí)例
        var socket = new WebSocket('ws://localhost:9090');

        // 打開Socket
        socket.onopen = function(event) {
            // 發(fā)送一個(gè)初始化消息
            socket.send("init msg");

        };
        socket.onmessage = function(event) {
            console.log('收到消息',event);

        };

        // 監(jiān)聽Socket的關(guān)閉
        socket.onclose = function(event) {
            console.log('關(guān)閉監(jiān)聽',event);
        };

        function  send()
        {
            socket.send("client msg");
        }
    /script>
/head>
body>
button onclick="send()">發(fā)送消息/button>
/body>
/html>