老雷socket编程之websocket实现

老雷socket编程之websocket实现

我们主要实现私聊和群聊两个功能,要在web端实现想微信QQ那样的即时通讯的功能，我们需要了解一下websocket。
websocket是一种可以双向通讯的长连接协议，http是获取完数据就关闭，websocket则可以一直连接，就像铺了一条管道一样，水可以一直流着。

一、websocket前端

    var ws = new WebSocket("ws://127.0.0.1.com:8282");
    ws.onopen=function(){
        var msg = JSON.stringify({
            type: "login",
            content: "login"
        });
        ws.send(msg);
    }

    ws.onmessage = function (e){
        console.log(e);
        //服务器发送的内容
        var res = JSON.parse(e.data);
        switch(res.type){
            case "login":

                break;
            case "pm":

                break;
            case "groupPm":

                break;

        }
    }
    ws.onerror=function (e){
        console.log(e);
    }
    ws.onclose=function (e){
        console.log(e);
    }

二、服务端

客户端发送http请求，带上Sec-WebSocket-Key，
服务端握手 加密key,发送给客户端。
双方能进行交流。

发送接收消息需要进行打包encode 解包decode。

<?php

class SocketService
{
    public $host="tcp://0.0.0.0:8000";
    private $address;
    private $port;
    private $_sockets;
    public $clients;
    public $maxid=1000;
    public function __construct($address = '', $port='')
    {
            if(!empty($address)){
                $this->address = $address;
            }
            if(!empty($port)) {
                $this->port = $port;
            }
    }

    public function onConnect($client_id){
        echo  "Client client_id:{$client_id}   \n";

    }

    public function onMessage($client_id,$msg){
        //发给所有的
        foreach($this->clients as $kk=>$cc){
            if($kk>0){
                $this->send($cc, $msg);
            }
        }
    }

    public function onClose($client_id){
        echo "$client_id close \n";
    }

    public function service(){
        //获取tcp协议号码。
        $tcp = getprotobyname("tcp");
        $sock = stream_socket_server($this->host, $errno, $errstr);;

        if(!$sock)
        {
            throw new Exception("failed to create socket: ".socket_strerror($sock)."\n");
        }
        stream_set_blocking($sock,0);
        $this->_sockets = $sock;
         echo "listen on $this->address $this->host ... \n";
    }

    public function run(){
        $this->service();
        $this->clients[] = $this->_sockets;
        while (true){
            $changes = $this->clients;
            //$write = NULL;
            //$except = NULL;
            stream_select($changes,  $write,  $except, NULL);
            foreach ($changes as $key => $_sock){
                if($this->_sockets == $_sock){ //判断是不是新接入的socket
                    if(($newClient = stream_socket_accept($_sock))  === false){
                        unset($this->clients[$key]);
                        continue;
                    }
                    $line = trim(stream_socket_recvfrom($newClient, 1024));
                    //握手
                    $this->handshaking($newClient, $line);
                    $this->maxid++;
                    $this->clients[$this->maxid] = $newClient;
                    $this->onConnect($this->maxid);
                } else {
                    $res=@stream_socket_recvfrom($_sock,  2048);
                    //客户端主动关闭
                    if(strlen($res) < 9) {
                        stream_socket_shutdown($this->clients[$key],STREAM_SHUT_RDWR);
                        unset($this->clients[$key]);
                        $this->onClose($key);
                    }else{
                        //解密
                        $msg = $this->decode($res);
                        $this->onMessage($key,$msg);
                    }

                }
            }
        }
    }

    /**
     * 握手处理
     * @param $newClient socket
     * @return int  接收到的信息
     */
    public function handshaking($newClient, $line){

        $headers = array();
        $lines = preg_split("/\r\n/", $line);
        foreach($lines as $line)
        {
            $line = chop($line);
            if(preg_match('/\A(\S+): (.*)\z/', $line, $matches))
            {
                $headers[$matches[1]] = $matches[2];
            }
        }
        $secKey = $headers['Sec-WebSocket-Key'];
        $secAccept = base64_encode(pack('H*', sha1($secKey . '258EAFA5-E914-47DA-95CA-C5AB0DC85B11')));
        $upgrade  = "HTTP/1.1 101 Web Socket Protocol Handshake\r\n" .
            "Upgrade: websocket\r\n" .
            "Connection: Upgrade\r\n" .
            "WebSocket-Origin: $this->address\r\n" .
            "WebSocket-Location: ws://$this->address:$this->port/websocket/websocket\r\n".
            "Sec-WebSocket-Accept:$secAccept\r\n\r\n";
        return stream_socket_sendto($newClient, $upgrade);
    }

    /**
     * 发送数据
     * @param $newClinet 新接入的socket
     * @param $msg   要发送的数据
     * @return int|string
     */
    public function send($newClinet, $msg){
        $msg = $this->encode($msg);
        stream_socket_sendto($newClinet, $msg);
    }
    /**
     * 解析接收数据
     * @param $buffer
     * @return null|string
     */
    public function decode($buffer){
        $len = $masks = $data = $decoded = null;
        $len = ord($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++) {
            $decoded .= $data[$index] ^ $masks[$index % 4];
        }
        return $decoded;
    }

    /**
    *打包消息
    **/
     public function encode($buffer) {
        $first_byte="\x81";
        $len=strlen($buffer);
        if ($len <= 125) {
            $encode_buffer = $first_byte . chr($len) . $buffer;
        } else {
            if ($len <= 65535) {
                $encode_buffer = $first_byte . chr(126) . pack("n", $len) . $buffer;
            } else {
                $encode_buffer = $first_byte . chr(127) . pack("xxxxN", $len) . $buffer;
            }
        }
        return $encode_buffer;
    }

    /**
     * 关闭socket
     */
    public function close(){
        return socket_close($this->_sockets);
    }
}

$sock = new SocketService('127.0.0.1','9000');
$sock->run();

三、常见应用

1.聊天室、群聊 实现类似QQ群的web版本

2.im私聊、客服 实现类似qq聊天，和即时客服交流

3.消息推送 建立即时的web消息推送

课后练习
实现聊天室 跟 个人聊天
前端格式

var msg = JSON.stringify({
type: "login",
content: "login"
});
var msg = JSON.stringify({
type: "group",
content: "login",
gid:123
});

var msg = JSON.stringify({
type: "pm",
content: "login",
uid:123
});