定期向Ratchet中的客户发送消息 [英] Periodically sending messages to clients in Ratchet

问题描述

我正试图定期发送"hello world！" Ratchet教程向所有连接到聊天服务器的客户端发送消息

I'm trying to periodically send a "hello world!" message to all clients connected to the chat-server from the Ratchet tutorial

我将在此处发布所有代码: Chat.php:

I will post all of the code here: Chat.php:

<?php
namespace MyApp;
use Ratchet\MessageComponentInterface;
use Ratchet\ConnectionInterface;

class Chat implements MessageComponentInterface {
    public $clients;

    public function __construct() {
        $this->clients = new \SplObjectStorage;
            }

    public function onOpen(ConnectionInterface $conn) {
        // Store the new connection to send messages to later
        $this->clients->attach($conn);

        echo "New connection! ({$conn->resourceId})\n";
    }

    //this worked but I don't want this behaviour
    public function onMessage(ConnectionInterface $from, $msg) {
        /*$numRecv = count($this->clients) - 1;
        echo sprintf('Connection %d sending message "%s" to %d other connection%s' . "\n"
            , $from->resourceId, $msg, $numRecv, $numRecv == 1 ? '' : 's');

        foreach ($this->clients as $client) {
            if ($from !== $client) {
                // The sender is not the receiver, send to each client connected
                $client->send($msg);
            }
        }*/
    }

    public function onClose(ConnectionInterface $conn) {
        // The connection is closed, remove it, as we can no longer send it messages
        $this->clients->detach($conn);

        echo "Connection {$conn->resourceId} has disconnected\n";
    }

    public function onError(ConnectionInterface $conn, \Exception $e) {
        echo "An error has occurred: {$e->getMessage()}\n";

        $conn->close();
    }
}

chat-server.php:

chat-server.php:

<?php
use Ratchet\Server\IoServer;
use MyApp\Chat;

    require dirname(__DIR__) . '/vendor/autoload.php';

    $server = IoServer::factory(
        new Chat(),
        8080
    );

    $server->run();

要测试我了解的文档数量，我在服务器循环中添加了一个计时器

To test how much of the docs I understood , I added a timer to the server's loop

    <?php
    use Ratchet\Server\IoServer;
    use MyApp\Chat;

        require dirname(__DIR__) . '/vendor/autoload.php';

        $server = IoServer::factory(
            new Chat(),
            8080
        );


        // My code here
        $server->loop->addPeriodicTimer(5, function () {
          echo  "custom loop timer working !";        
        });


        $server->run();

，并且在启动服务器后每五秒钟输出一次该字符串就可以正常工作.

and it worked fine outputting that string every five seconds after starting the server.

现在，我尝试这样做，尝试向教程中称为Chat的MessageComponentInterface中存储的客户端发送消息

Now I tried doing it like so, trying to send a message to clients stored in the MessageComponentInterface called Chat from the tutorial

$server->loop->addPeriodicTimer(5, function () {        
    foreach ($server->app->clients as $client) {                  
            $client->send("hello client");          
    }
});

但是我发现$ server-> app是NULL，这可能是因为我现在在function()块中.对于面向对象的PHP，我不是专家，这个小项目将肯定对我有很大帮助. 如何访问计时器内部服务器的称为app的MessageComponentInterface属性，然后将数据发送到存储在其中的客户端?

But I'm getting that $server->app is NULL which is probably because I'm now inside the function() block .I'm not an expert when it comes to Object oriented PHP, and this little project will sure help me a lot. How can I access the MessageComponentInterface called app property of the server inside the timer and then send data to the clients stored in there?

推荐答案

$server未在函数作用域中定义，默认情况下，父作用域的变量不会继承到子作用域.闭包可以使用use语言构造从父范围继承变量.

$server isn't defined in the function scope and variables from the parent scope don't get inherited to the child scope by default. Closures can inherit variables from the parent scope by using the use language construct.

$server->loop->addPeriodicTimer(5, function () use ($server) {        
    foreach ($server->app->clients as $client) {                  
            $client->send("hello client");          
    }
});

有关匿名函数(关闭)的更多信息: https://secure.php .net/manual/en/functions.anonymous.php
有关变量范围的更多信息: https://secure.php.net/manual/en/language.variables.scope.php

More information about anonymous functions (closures): https://secure.php.net/manual/en/functions.anonymous.php
More information about variables scope: https://secure.php.net/manual/en/language.variables.scope.php

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