An example of php implementing socket push technology

Before socket appeared, there were ajax timing request, long polling and other schemes, but they could not meet the requirements, so socket came into being.

socket Basic Function socket

Summarize the commonly used socket functions

Server: socket_create Create socket Set Basic Parameters

socket_bind Bind ip and port number

socket_listen Listening

Connections for socket_accept clients

socket_read Reading data from the client

socket_write Send data to individual clients

socket_close Close Connection

Client: socket_create Create socket Set Basic Parameters

socket_connect Connect socket

socket_write Send data to server

socket_read Read server data

socket_close close connection

H5websocket don't say much, link on

OK, start posting code ~

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Server-side code:

<?php
class WS {
 var $master;
 var $sockets = array();
 var $debug = false;//true For debug mode, output log Journal 
 var $handshake = array();
 function __construct($address, $port){
 $this->master=socket_create(AF_INET, SOCK_STREAM, SOL_TCP) or die("socket_create() failed");
 socket_set_option($this->master, SOL_SOCKET, SO_REUSEADDR, 1) or die("socket_option() failed");
 socket_bind($this->master, $address, $port)  or die("socket_bind() failed");
 socket_listen($this->master,20)  or die("socket_listen() failed");
 
 $this->sockets[] = $this->master;
 $this->say("Server Started : ".date('Y-m-d H:i:s'));
 $this->say("Listening on : ".$address." port ".$port);
 $this->say("Master socket : ".$this->master."\n");
 
 while(true){
 $socketArr = $this->sockets;
 $write = NULL;
 $except = NULL;
 socket_select($socketArr, $write, $except, NULL); // Automatically select the socket  If it's a handshake   Automatic host selection 
 foreach ($socketArr as $socket){
 if ($socket == $this->master){ // Host 
  $client = socket_accept($this->master);
  if ($client < 0){
  $this->log("socket_accept() failed");
  continue;
  } else{
  $this->connect($client);
  }
 } else {
  $bytes = @socket_recv($socket,$buffer,2048,0);
  if ($bytes == 0){
  $this->disConnect($socket);
  }
  else{
  $key = array_search($socket, $this->sockets);
  if (empty($this->handshake) || !isset($this->handshake[$key]) || !$this->handshake[$key]){
  $this->doHandShake($socket, $buffer, $key);
  }
  else{
  $buffer = $this->decode($buffer);
  echo $buffer.PHP_EOL;
  $key = array_search($socket, $this->sockets);
  $arr = $this->sockets;
  array_shift($arr);
  foreach ($arr as $s){
  $this->send($s, $buffer);
  }
  }
  }
 }
 }
 }
 }
 
 function send($client, $msg){
 $msg = $this->frame($msg);
 socket_write($client, $msg, strlen($msg));
 }
 function connect($socket){
 array_push($this->sockets, $socket);
 $this->say("\n" . $socket . " CONNECTED!");
 $this->say(date("Y-n-d H:i:s"));
 }
 function disConnect($socket){
 $index = array_search($socket, $this->sockets);
 socket_close($socket);
 $this->say($socket . " DISCONNECTED!");
 if ($index >= 0){
 echo 'unset index is:'.PHP_EOL;
 unset($this->sockets[$index]);
 }
 }
 function doHandShake($socket, $buffer, $handKey){
 $this->log("\nRequesting handshake...");
 $this->log($buffer);
 list($resource, $host, $origin, $key) = $this->getHeaders($buffer);
 $this->log("Handshaking...");
 $upgrade = "HTTP/1.1 101 Switching Protocol\r\n" .
  "Upgrade: websocket\r\n" .
  "Connection: Upgrade\r\n" .
  "Sec-WebSocket-Accept: " . $this->calcKey($key) . "\r\n\r\n"; // Must end with two carriage returns 
 $this->log($upgrade);
 $sent = socket_write($socket, $upgrade, strlen($upgrade));
 $this->handshake[$handKey]=true;
 $this->log("Done handshaking...");
 return true;
 }
 function getHeaders($req){
 $r = $h = $o = $key = null;
 if (preg_match("/GET (.*) HTTP/" ,$req,$match)) { $r = $match[1]; }
 if (preg_match("/Host: (.*)\r\n/" ,$req,$match)) { $h = $match[1]; }
 if (preg_match("/Origin: (.*)\r\n/" ,$req,$match)) { $o = $match[1]; }
 if (preg_match("/Sec-WebSocket-Key: (.*)\r\n/",$req,$match)) { $key = $match[1]; }
 return array($r, $h, $o, $key);
 }
 function calcKey($key){
 // Based on websocket version 13
 $accept = base64_encode(sha1($key . '258EAFA5-E914-47DA-95CA-C5AB0DC85B11', true));
 return $accept;
 }
 function decode($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 $decoded;
 }
 function frame($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;
 }
 
 function say($msg = ""){
 echo $msg . "\n";
 }
 function log($msg = ""){
 if ($this->debug){
 echo $msg . "\n";
 } 
 }
}
 
new WS('localhost', 4000);

Client code (H5):

<html>
 <head>
 <title>demo</title>
 <script src="https://cdn.bootcss.com/jquery/1.9.1/jquery.min.js"></script>
 </head>
 <body>
 <input type="text" id="content">
 <input type="button" value="send" id="send">
 <script type="text/javascript">
  var ws = new WebSocket("ws://localhost:4000");
  ws.onopen = function(){
  console.log(" Successful handshake ");
  }
  ws.onmessage = function(e){
  console.log("message:" + e.data);
  }
  ws.onerror = function(){
  console.log("error");
  }
  $("#send").click(function(){
  content = $("#content").val();
  console.log(content);
  ws.send(content);
  })
 </script>
 </body>
</html>

Then execute php demo. php to open socket (steal a trick from operation and maintenance, and execute nohup php demo. php under linux & Can be executed in the background), the browser open multiple index. html, you can establish communication.

Code parsing:

1. The attribute $sockets array holds each accept connection (I don't know if this description is correct);

2. The attribute $handshake array holds whether the connection is in the connection state;