Detailed explanation of the steps to implement websocket real-time message push in PHP

<?php
/**
 * Created by xwx
 * Date: 2017/10/18
 * Time: 14:33
 */
class SocketService
{
  private $address = &#39;0.0.0.0&#39;;
  private $port = 8083;
  private $_sockets;
  public function construct($address = &#39;&#39;, $port=&#39;&#39;)
  {
      if(!empty($address)){
        $this->address = $address;
      }
      if(!empty($port)) {
        $this->port = $port;
      }
  }
  public function service(){
    //获取tcp协议号码。
    $tcp = getprotobyname("tcp");
    $sock = socket_create(AF_INET, SOCK_STREAM, $tcp);
    socket_set_option($sock, SOL_SOCKET, SO_REUSEADDR, 1);
    if($sock < 0)
    {
      throw new Exception("failed to create socket: ".socket_strerror($sock)."\n");
    }
    socket_bind($sock, $this->address, $this->port);
    socket_listen($sock, $this->port);
    echo "listen on $this->address $this->port ... \n";
    $this->_sockets = $sock;
  }
  public function run(){
    $this->service();
    $clients[] = $this->_sockets;
    while (true){
      $changes = $clients;
      $write = NULL;
      $except = NULL;
      socket_select($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 = socket_accept($_sock)) === false){
            die('failed to accept socket: '.socket_strerror($_sock)."\n");
          }
          $line = trim(socket_read($newClient, 1024));
          $this->handshaking($newClient, $line);
          //获取client ip
          socket_getpeername ($newClient, $ip);
          $clients[$ip] = $newClient;
          echo "Client ip:{$ip}  \n";
          echo "Client msg:{$line} \n";
        } else {
          socket_recv($_sock, $buffer, 2048, 0);
          $msg = $this->message($buffer);
          //在这里业务代码
          echo "{$key} clinet msg:",$msg,"\n";
          fwrite(STDOUT, 'Please input a argument:');
          $response = trim(fgets(STDIN));
          $this->send($_sock, $response);
          echo "{$key} response to Client:".$response,"\n";
        }
      }
    }
  }
  /**
   * 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 socket_write($newClient, $upgrade, strlen($upgrade));
  }
  /**
   * 解析接收数据
   * @param $buffer
   * @return null|string
   */
  public function message($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;
  }
  /**
   * 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 = $this->frame($msg);
    socket_write($newClinet, $msg, strlen($msg));
  }
  public function frame($s) {
    $a = str_split($s, 125);
    if (count($a) == 1) {
      return "\x81" . chr(strlen($a[0])) . $a[0];
    }
    $ns = "";
    foreach ($a as $o) {
      $ns .= "\x81" . chr(strlen($o)) . $o;
    }
    return $ns;
  }
  /**
   * 关闭socket
   */
  public function close(){
    return socket_close($this->_sockets);
  }
}
$sock = new SocketService();
$sock->run();

<!doctype html>
<html lang="en">
 <head>
 <meta charset="UTF-8">
 <meta name="viewport" content="width=device-width,initial-scale=1, maximum-scale=1, user-scalable=no">
 <title>websocket</title>
 </head>
 <body>
 <input id="text" value="">
 <input type="submit" value="send" onclick="start()">
 <input type="submit" value="close" onclick="close()">
<p id="msg"></p>
 <script>
 /**
 0：未连接
1：连接成功，可通讯
2：正在关闭
3：连接已关闭或无法打开
*/
  //创建一个webSocket 实例
  var webSocket = new WebSocket("ws://192.168.31.152:8083");
  webSocket.onerror = function (event){
    onError(event);
  };
  // 打开websocket
  webSocket.onopen = function (event){
    onOpen(event);
  };
  //监听消息
  webSocket.onmessage = function (event){
    onMessage(event);
  };
  webSocket.onclose = function (event){
    onClose(event);
  }
  //关闭监听websocket
  function onError(event){
    document.getElementById("msg").innerHTML = "<p>close</p>";
    console.log("error"+event.data);
  };
  function onOpen(event){
    console.log("open:"+sockState());
    document.getElementById("msg").innerHTML = "<p>Connect to Service</p>";
  };
  function onMessage(event){
    console.log("onMessage");
    document.getElementById("msg").innerHTML += "<p>response:"+event.data+"</p>"
  };
  function onClose(event){
    document.getElementById("msg").innerHTML = "<p>close</p>";
    console.log("close:"+sockState());
    webSocket.close();
  }
  function sockState(){
    var status = [&#39;未连接&#39;,&#39;连接成功，可通讯&#39;,&#39;正在关闭&#39;,&#39;连接已关闭或无法打开&#39;];
      return status[webSocket.readyState];
  }
 function start(event){
    console.log(webSocket);
    var msg = document.getElementById(&#39;text&#39;).value;
    document.getElementById(&#39;text&#39;).value = &#39;&#39;;
    console.log("send:"+sockState());
    console.log("msg="+msg);
    webSocket.send("msg="+msg);
    document.getElementById("msg").innerHTML += "<p>request"+msg+"</p>"
  };
  function close(event){
    webSocket.close();
  }
 </script>
 </body>
</html>