README

这是一个使用 GraphQL over WebSocket 协议 和 Ratchet 实现的 PHP 库。

正在进行

这个库正在积极开发中，其接口、实现和使用可能会发生变化。如果您不打算投入时间重写基于此库的应用程序，请不要使用它。

用法

<?php

use GraphQL\Language\AST\OperationDefinitionNode;
use GraphQLWs\GraphQLWsSubscriberInterface;
use GraphQLWs\GraphQLWsSubscriptionServer;
use Ratchet\Http\HttpServer;
use Ratchet\Server\IoServer;
use Ratchet\WebSocket\WsConnection;
use Ratchet\WebSocket\WsServer;
use React\EventLoop\Factory;
use React\Socket\Server as Reactor;
use Symfony\Component\HttpKernel\Log\Logger;

class RedisEventQueue implements GraphQLWsSubscriberInterface {
  
  /**
   * The subscriptions listening to our GraphQL 
   */
  protected array $subscriptions = [];

  /**
   * Called with new subscribers.
   *
   * {@inheritdoc} 
   */  
  public function onSubscribe(string $subscription_id, WsConnection $client, OperationDefinitionNode $query, ?string $operationName = NULL, ?array $variables = NULL) : void{
    $this->subscriptions[$subscription_id] = [
      'client' => $client,
      'query' => $query,
      'operationName' => $operationName,
      'variables' => $variables,
    ];
  }
  
  /**
   * Called when connections are closed.
   *
   * {@inheritdoc} 
   */  
  public function onComplete(string $subscription_id) : void{
    unset($this->subscriptions[$subscription_id]);
  }
  
  /**
   * Example function receiving data from an event system (e.g. a Redis queue). 
   */
  public function onData($data) {
    // For this example we simply naïvely write the data to the client. This is
    // most certainly a GraphQL error. This is where you'd actually resolve the
    // queries your subscribers are subscribed to with the new data. This can be
    // made easier by doing some double bookkeeping in the onSubscribe event
    // handler but that's out of the scope of this example.  
    foreach ($this->subscriptions as $subscription) {
      $subscription['client']->send(json_encode($data));
    }
  }


}

$ws_address = "localhost:8000";

$logger = new Logger();
$event_loop = Factory::create();

// Something that receives new data from an external system and keeps track of
// subscriptions. Any new data is sent to the subscriptions that have asked for
// the data. 
$subscription_handler = new RedisEventQueue($event_loop);

// Set up the Websocket server. It requires an event loop to handle some
// timeouts that are part of the GraphQL WS Protocol. 
$subscription_server = new GraphQLWsSubscriptionServer($logger, $event_loop);
$subscription_server->addEventHandler($subscription_handler);

// Set up our actual stack that handles HTTP and WebSockets. The server above is
// only the protocol handler itself.
$ws_app = new HttpServer(new WsServer($subscription_server));
$ws_socket = new Reactor($ws_address, $this->eventLoop); 
new IoServer($ws_app, $ws_socket, $this->eventLoop);

$logger->info(
  "Listening for WebSocket connections on ws://{address}",
  ["address" => $ws_address]
);

// Kick-off the React event loop to start our server.
$event_loop->run();