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PHP Websocket客户端-保持连接打开

websocket php

0

Oliver M Grech · 技术社区 · 5 年前

我在用 PHP-WSS 在laravel应用程序中,需要保持websocket客户端打开,才能从websocket服务器接收各种消息。

到目前为止,我构建了一个CLI php脚本,可以执行并等待消息到达。

我构建了以下函数来测试。。。

问题是,为了让连接对可能从服务器发送的任何消息保持打开状态,使用while(true)循环按如下方式进行连接是一种好方法吗?我还能做得更好吗?(对我来说,它看起来很脏,希望改进它并正确地做)

function testWebsocketClient() {
    $url = 'wss://example.com/?token=xyz123456';
    $client = new WebSocketClient($url, new ClientConfig());
    while(true){
        sleep(5);
        $client->send('test');
        $return = $client->receive(); // test received OK
    }
    return $return;
}

更新:任何使用PHP-WSS的人我都发现了一个连接错误。php中的广播方法。

原始函数尝试在死连接上发送,显示以下错误空读;连接断了? (注意EOF=true)

public function broadCast(string $data): void
{
    foreach ($this->clients as $client) {
        if (is_resource($client) ) { // check if not yet closed/broken etc
            fwrite($client, $this->encode($data));
        } else {
            echo 'Skipping a closed connection';
        }
    }
}

我把它改成了

public function broadCast(string $data): void
{
    foreach ($this->clients as $client) {
        //echo PHP_EOL. stream_get_status($client) .PHP_EOL;
        $clientMeta = ( stream_get_meta_data($client) );
        $clientEof = $clientMeta['eof'];
        if (is_resource($client) && $clientEof == false ) { // check if not yet closed/broken etc
            fwrite($client, $this->encode($data));
        } else {
            echo 'Skipping a closed connection';
        }
    }
}

0 回复 | 直到 5 年前

1

Daniil Loban 5 年前

由于呈现页面的php脚本完成了执行,因此需要使用js脚本在客户机上实现WebSocket

<?php 
   // here output your page
   wss_path = 'wss://example.com/?token=xyz123456';
?>

// JS script (see its working results in console by pressing `F12`)
<script>
  let socket = new WebSocket(<?= wss_path ?>);

  socket.onopen = function(e) {
    console.log('[open] Connection opened');
    socket.send("Hi! I am a new web-socket client.");
  };

  socket.onmessage = function(event) {
    const message = JSON.parse(event.data);
    console.log('From the server:', message);
  };

  socket.onclose = function(event) {
    if (event.wasClean) {
      console.log(`[close] Connetion closed clearly, code=${event.code} reason=${event.reason}`);
    } else {
      console.log('[close] Ð¡onnection closed unexpectedly');
    }
  };

  socket.onerror = function(error) {
    console.log(`[error] ${error}`);
  };
</script>

2

0

Oliver M Grech 5 年前

经过整整一周的努力,我找到了一个解决办法。。。

如果缓冲区为空,则有一个错误处理程序会引发异常,从而结束客户端。

在WscMain。php文件,内置受保护的函数读取方法,删除/注释掉(或根据您的喜好和需要更改)以下错误处理程序(大约第302行)

if(false){ // added a false condition so the code within doesn't execute
    if (false && $buff === false ) {
        $metadata = stream_get_meta_data($this->socket);
        throw new ConnectionException(
            'Broken frame, read ' . strlen($data) . ' of stated '
            . $len . ' bytes.  Stream state: '
            . json_encode($metadata),
            CommonsContract::CLIENT_BROKEN_FRAME
        );
    }

    if (false && $buff === '') {
        //print_r($this->socket);
        
        $metadata = stream_get_meta_data($this->socket);
        throw new ConnectionException(
            'Empty read; connection dead?  Stream state: ' . json_encode($metadata). ' '.PHP_EOL.( (int) $this->socket ) ,
            CommonsContract::CLIENT_EMPTY_READ
        );
    }
}

PS:就我而言,我还在配置中设置了一个非常小的(1秒)读取超时,如下所示。(此测试函数是从CLI PHP脚本执行的)

function runWebsocketClientTest(){

    echo PHP_EOL;
    echo __FUNCTION__;
    echo PHP_EOL;
    $timeout = 1;
    $return = '';
    $config = new ClientConfig();
    $config->setTimeout($timeout);
    $client = new WebSocketClient('ws://localhost:8000', $config);

    while($client->isConnected()){
        if($client->isConnected()){ // this might be unnecessary 
            echo $client->receive();
        }
    }
    
}

希望这能帮助别人,感谢所有帮助过你的人。