如何在 ratchetphp 上自动重新连接客户端？

Question

我正在使用 rachetphp 为 api 服务器创建客户端。 但是我有一个问题，当我的连接关闭时，无论什么原因，我都无法自动重新连接。

这里是我使用的库：https://github.com/ratchetphp/Pawl

<?php

require __DIR__ . '/vendor/autoload.php';

$loop = React\EventLoop\Factory::create();
$connector = new Ratchet\Client\Connector($loop);

$connector('ws://127.0.0.1:9000', ['protocol1', 'subprotocol2'], ['Origin' => 'http://localhost'])
->then(function(Ratchet\Client\WebSocket $conn) {
    $conn->on('message', function(\Ratchet\RFC6455\Messaging\MessageInterface $msg) use ($conn) {
        echo "Received: {$msg}\n";
        $conn->close();
    });

    $conn->on('close', function($code = null, $reason = null) {
        echo "Connection closed ({$code} - {$reason})\n";
    });

    $conn->send('Hello World!');
}, function(\Exception $e) use ($loop) {
    echo "Could not connect: {$e->getMessage()}\n";
    $loop->stop();
});

$loop->run();

我想在连接关闭后每隔几秒尝试重新连接。 有什么想法吗？

Answer 1

如果您安装了 pnctl (http://php.net/manual/en/book.pcntl.php)，您只需将“关闭”处理程序更改为：

$conn->on('close', function($code = null, $reason = null) {
    echo "Connection closed ({$code} - {$reason})\n";

    // restart myself
    global $argv;
    pcntl_exec($_SERVER['_'], $argv);
    exit();

}); 

对我来说这更简单，因为我还没有提取 $loop 和 $connector，我只是在使用

\Ratchet\Client\connect($ws_url, [], $headers)
    ->then(function ($conn) {
        echo "connected\n";
        ...

为了在多个地方处理它，我创建了一个小助手函数，用于调用这些事件（根据情况，我添加了延迟）。

function restartMyself() {
  global $argv;
  pcntl_exec($_SERVER['_'], $argv);
  exit();
}

Answer 2

这个想法很简单，但需要一些重构。我们必须将重新连接代码放在连接关闭时执行的处理程序中。为此，我们在 self 内部传递了 $app 函数。

require __DIR__ . '/vendor/autoload.php';

$loop = React\EventLoop\Factory::create();
$connector = new Ratchet\Client\Connector($loop);

$app = function (Ratchet\Client\WebSocket $conn) use ($connector, $loop, &$app) {
    $conn->on('message', function (\Ratchet\RFC6455\Messaging\MessageInterface $msg) use ($conn) {
        echo "Received: {$msg}\n";
        $conn->close();
    });

    $conn->on('close', function ($code = null, $reason = null) use ($connector, $loop, $app) {
        echo "Connection closed ({$code} - {$reason})\n";

        //in 3 seconds the app will reconnect
        $loop->addTimer(3, function () use ($connector, $loop, $app) {
            connectToServer($connector, $loop, $app);
        });
    });

    $conn->send('Hello World!');
};

function connectToServer($connector, $loop, $app)
{
    $connector('ws://127.0.0.1:9000', ['protocol1', 'subprotocol2'], ['Origin' => 'http://localhost'])
        ->then($app, function (\Exception $e) use ($loop) {
            echo "Could not connect: {$e->getMessage()}\n";
            $loop->stop();
        });
}

connectToServer($connector, $loop, $app);

$loop->run();

这个想法是，当连接接收到close 事件时，我们使用connectToServer 函数进行重新连接：

$conn->on('close', function ($code = null, $reason = null) use ($connector, $loop, $app) {
    echo "Connection closed ({$code} - {$reason})\n";

    //in 3 seconds the app will reconnect
    $loop->addTimer(3, function () use ($connector, $loop, $app) {
        connectToServer($connector, $loop, $app);
    });
});