如何将ZeroMQ套接字与Ratchet web-socket库绑定,以实现php应用程序的实时应用？

Question

我只是这个涉及websocket,Ratchet和ZeroMQ的整个领域的初学者.

基本了解:

websocket 是有助于在服务器和客户端之间创建开放连接的东西.

Ratchet 是一个基于PHP的库,它使用PHP的核心Socket函数来创建一个PHP套接字框架,允许我们简化PHP套接字编程.

ZeroMQ 是一个套接字库,可以帮助非棘轮应用程序(其他PHP脚本)通过Ratchet Socket和web-socket发送数据.

我正在按照棘轮中关于'hello world'和'pusher'的教程进行操作,但它们似乎都是不完整的,只讲授如何使用控制台.我也在github中找到了棘轮示例,但没有正确记录.我正在寻找一个完整的例子(带有专用的html页面和javascript)

下面是我正在处理的代码:这是我正在进行Ajax请求的控制器的方法之一.这个方法会创建一个新帖子(比方说).我想在ZeroMq的帮助下通过广播/推送在多个客户端的浏览器中动态更新帖子列表.

控制器中的方法:

public function create_new_post(){
    // ------
    // code to create a new post.
    // -------

    // After creating a post
    $response = [
        'new_post_title'    => $title,
        'post_id'           => $id
    ];

    $context = new ZMQContext();
    $socket = $context->getSocket(ZMQ::SOCKET_PUSH, 'my pusher');
    $socket->connect("tcp://localhost:8000");
    $socket->send(json_encode($response));

}

推送文件:

use Ratchet\ConnectionInterface;
use Ratchet\Wamp\WampServerInterface;

class Pusher implements WampServerInterface{

     public function onPostEntry($data){
         // Data that were sent by ZeroMQ through create_new_post() method
         $entry_data = json_decode($data);      

         // AND AFTER THIS, I DONT HAVE CLUE OF WHAT TO DO NEXT !!             

     }
}

用于运行服务器的Shell脚本:

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

$loop   = React\EventLoop\Factory::create();
$pusher = new MyApp\Pusher;

// Listen for the web server to make a ZeroMQ push after an ajax request
$context = new React\ZMQ\Context($loop);
$pull = $context->getSocket(ZMQ::SOCKET_PULL);
$pull->bind('tcp://127.0.0.1:8000'); 
$pull->on('message', array($pusher, 'onBidEntry'));

// Set up our WebSocket server for clients wanting real-time updates
$webSock = new React\Socket\Server($loop);
$webSock->listen(8080, '0.0.0.0'); 
$webServer = new Ratchet\Server\IoServer(
    new Ratchet\Http\HttpServer(
        new Ratchet\WebSocket\WsServer(
            new Ratchet\Wamp\WampServer(
                $pusher
            )
        )
    ),
    $webSock
);

$loop->run();

Shell脚本只告诉它将在端口8080中提供服务,但是我如何提及我的路由.让我们说我只想在页面'mysite/allposts'中打开连接.此外,我必须在客户端编写的脚本(javascript文件)以及如何通过客户端更新特定DOM对象来接收这些新数据.

Answer 1

我按照你所说的例子进行了操作。它们对我来说似乎并不完整，但我明白你的意思。Ratchet 是一个服务器端脚本，仅允许您编写一个实现 websockets 并能够侦听 ZMQ 消息的服务。您将在命令行上启动 Ratchet 脚本，它作为服务与 Apache 并行运行。

这一切都独立于 websocket 的客户端。正如他们推荐的那样，我在客户端使用了 Autobahn.js。该库实现了 WAMP 协议。它最大限度地简化了客户端代码。

您的代码的问题是，它class Pusher implements WampServerInterface没有public function onPostEntry. 这个类必须实现WampServerInterface，这意味着它必须至少具有以下功能：

• onSubscribe(ConnectionInterface $conn, $topic)
• onUnSubscribe(ConnectionInterface $conn, $topic)
• onOpen(ConnectionInterface $conn)
• onClose(ConnectionInterface $conn)
• onPublish(ConnectionInterface $conn, $topic, $event, 数组 $exclude, 数组 $eligible
• onError(ConnectionInterface $conn, \Exception $e)
• onZMQMessage($jsondata)

还可以有其他更高级的功能，例如call在客户端上执行远程过程。

在发送方（ZMQ 消息），输入以下代码：

$zmq = new ZMQWrapper;
$zqm->publish('posts', $response);

class ZMQWrapper {
    function __construct(){
        $this->context = new ZMQContext();
        $this->socket = $this->context->getSocket(ZMQ::SOCKET_PUSH);
        $this->socket->setSockOpt(ZMQ::SOCKOPT_LINGER, 500);
        $this->socket->connect("tcp://127.0.0.1:" . ZMQ_PORT);
    }
    function publish($topic, $msg){
        $data = ['topic' => "mb.$topic", 'msg' => $msg];
        $this->socket->send(json_encode($data), ZMQ::MODE_DONTWAIT);
    }
}

在推送文件中添加如下内容：

public function onSubscribe(ConnectionInterface $conn, $topic) {
    $log = $this->getLogger();
    $topicId = $topic->getId();
    $log->info(sprintf('A client subscribed to %s', $topicId));
    // you could broadcast that user x joined the discussion
}
public function onUnSubscribe(ConnectionInterface $conn, $topic) {
    $log = $this->getLogger();
    $topicId = $topic->getId();
    $log->info(sprintf('A client unsubscribed from %s', $topicId));
    // you could broadcast that user x leaved the discussion
}
public function onOpen(ConnectionInterface $conn) {
    $log = $this->getLogger();
    $log->info(sprintf('Client %d connected', $conn->resourceId));
    $this->clients[$conn->resourceId] = array(); // this will allow you to save state information of the client, you can modify in onSubscribe and onUnsubscribe
    // clients will contain the list of all clients
}
public function onClose(ConnectionInterface $conn) {
    $log = $this->getLogger();
    $log->info(sprintf('Client %d disconnected', $conn->resourceId));
    // you could broadcast that user x leaved the discussion
}
public function onPublish(ConnectionInterface $conn, $topic, $event, array $exclude, array $eligible) {
    $log = $this->getLogger();
    $topicId = $topic->getId();
    $log->info(sprintf('Client %d published to %s : %s', $conn->resourceId, $topicId, json_encode($event)));
    foreach($topic->getIterator() as $peer){
        if(!in_array($peer->WAMP->sessionId, $exclude)){
            $peer->event($topicId, $event);
        }
    }
}

最后一块在客户端。如果用户打开该页面mysite/allposts，则在 javascript 中包含autobahn.js. websocket 将在变量下可用ab。然后你做：

打开页面时：

var currentSession;
ab.connect(
    Paths.ws,
    function(session) { // onconnect
        currentSession = session
        onWsConnect(session)
    },
    function(code, reason, detail) {// onhangup
        onWsDisconnect(code, reason, detail)
    },{
        maxRetries: 60,
        retryDelay: 2000,
        skipSubprotocolCheck: true
    }
)
currentSession.subscribe('posts', onPostReceived)

function onPostReceived(topic, message){
    //display the new post
}

关闭页面时：

currentSession.unsubscribe(topic)

你注意到我把一切都保持得很笼统。这允许我让同一系统处理多种类型的消息。不同之处在于 ZMQ 消息和 的参数currentSession.subscribe。

在我的实现中，我还跟踪打开连接的登录用户，但我剥离了这部分代码。

我希望这能帮到您。