Swoole websocket service

What is? WebSocket

WebSocker The protocol is based on TCP A new network protocol . It realizes full duplex between browser and server （full-duplex） signal communication - Allow the server to actively send information to the client .

Why WebSocket

defects ：HTTP Communication can only be initiated by the client

WebSocker characteristic

1. Based on the TCP The agreement above
2. Low performance overhead and efficient communication
3. The client can communicate with any server
4. Protocol identifier ws  wss
5. Persistent network communication protocol

ws_server.php

// establish WebSocket Server object , monitor 0.0.0.0:9502 port 
$ws = new Swoole\WebSocket\Server('0.0.0.0', 9502);

// monitor WebSocket Connection open event 
$ws->on('Open', function ($ws, $request) {
    $ws->push($request->fd, "hello, welcome\n");
});

// monitor WebSocket News events 
$ws->on('Message', function ($ws, $frame) {
    echo "Message: {$frame->data}\n";
    $ws->push($frame->fd, "server: {$frame->data}");
});

// monitor WebSocket Connection close event 
$ws->on('Close', function ($ws, $fd) {
    echo "client-{$fd} is closed\n";
});

$ws->start();

• When the client sends information to the server , Server side trigger  onMessage  Event callback
• The server side can call  $server->push()  To a client （ Use $fd identifier ） Send a message

Run the program

php ws_server.php

have access to Chrome Browser to test ,JS The code is ：

var wsServer = 'ws://127.0.0.1:9502';
var websocket = new WebSocket(wsServer);
websocket.onopen = function (evt) {
    console.log("Connected to WebSocket server.");
};

websocket.onclose = function (evt) {
    console.log("Disconnected");
};

websocket.onmessage = function (evt) {
    console.log('Retrieved data from server: ' + evt.data);
};

websocket.onerror = function (evt, e) {
    console.log('Error occured: ' + evt.data);
};

WebSocket In addition to providing WebSocket Besides the function , In fact, it can also handle HTTP A long connection . Just add  onRequest  Event monitoring can be realized Comet programme HTTP Long polling .