Overview

This library was created to experiment with zend expressive using React PHP and is based on React\Http. Mileage may vary.

A large portion of this code leverages existing libraries such as guzzlehttp's psr7 library, zend diactoros, zend expressive, zend stratigility and zend service manager.

Requirements

• PHP 5.6+

Installation

$ composer install

Usage

This library alters the functionality of Zend\Expressive\Application slightly to allow for deferred processing from middleware. If a middleware application returns an instance of DeferredResponse the application will wait to emit until the promise has been resolved. DeferredResponse must be created with a React\Promise\Promise object.

Example:

function($request, $response) use ($eventLoop) {
    // create a request, wait 1-5 seconds and then return a response.
    $deferred = new Deferred();
    $eventLoop->addTimer(rand(1, 5), function() use ($deferred){
        echo 'Timer executed' . PHP_EOL;
        $deferred->resolve(new Diactoros\Response\HtmlResponse('Deferred response.'));
    });

    return new \ExpressiveAsync\DeferredResponse($deferred->promise());
}

Example

$serviceManager = new \Zend\ServiceManager\ServiceManager();
$eventLoop      = Factory::create();
$socketServer   = new SocketServer($eventLoop);
$httpServer     = new Server($socketServer);

$serviceManager->setFactory('EventLoop',function() use ($eventLoop) { return $eventLoop; });
$serviceManager->setInvokableClass(
    'Zend\Expressive\Router\RouterInterface',
    'Zend\Expressive\Router\FastRouteRouter'
);

$router = new \Zend\Expressive\Router\FastRouteRouter();

// Example of a regular request
$router->addRoute(new \Zend\Expressive\Router\Route(
    '/',
    function($request, $response) use ($eventLoop) {
        return new Diactoros\Response\HtmlResponse('Hello World.');
    },
    ['GET'],
    'home'
));

// Example of a deferred request
$router->addRoute(new \Zend\Expressive\Router\Route(
    '/deferred',
    function($request, $response) use ($eventLoop) {
        // create a request, wait 1-5 seconds and then return a response.
        $deferred = new Deferred();
        $eventLoop->addTimer(rand(1, 5), function() use ($deferred){
            echo 'Timer executed' . PHP_EOL;
            $deferred->resolve(new Diactoros\Response\HtmlResponse('Deferred response.'));
        });

        return new \ExpressiveAsync\DeferredResponse($deferred->promise());
    },
    ['GET'],
    'deferred'
));

$application = new Application(
    $router,
    $serviceManager,
    function($request, $response) {
        echo 'final handler was called.' . PHP_EOL;
        return new Diactoros\Response\HtmlResponse('Not Found.', 404);
    }
);
$connectionHandler = new ExpressiveAsync\ExpressiveConnectionHandler($application);
$httpServer->on('request', $connectionHandler);
$socketServer->listen('10091');
$eventLoop->run();

Connection Events

The ExpressiveConnectionHandler emits several events during the lifecycle of a request.

ExpressiveConnectionHandler::EVENT_REQUEST [$connection, &$request, &$response]

Before the middleware application is executed this event will be emitted. The request and response objects are passed in by reference allowing for modification.

$connectionHandler = new ExpressiveAsync\ExpressiveConnectionHandler($application);
$connectionHandler->on(ExpressiveConnectionHandler::EVENT_REQUEST, function ($conn, &$request, $response) {
    $request = $request->withAttribute('request-start', microtime(true))
});

ExpressiveConnectionHandler::EVENT_END [$connection, $request, &$response]

Before the response is written to the connection but after the middleware has executed. The response object is passed by reference.

$connectionHandler->on('end', function($conn, $request, $response) use ($logger) {
    $logger->timing('app.timing', (microtime(true) - $request->getAttribute('request-start')) * 1000);
});

ExpressiveConnectionHandler::EVENT_CONNECTION_END [$connection]

Emitted once the connection has been ended.

ExpressiveConnectionHandler::EVENT_CONNECTION_CLOSE [$connection]

Emitted once the connection close has been called.

Run the Example

An example server has been provided. To run simply execute the following in the terminal from the root directory.

    $ php bin/server.php

Open your browser to http://127.0.0.1:10091

More Information

For additional information on how to get started see the zend-expressive github page.

Notes

Currently this example contains BufferedStream, which isn't using streams at all. The Response and Request objects created by zend and guzzle all use php://memory or php://temp, I am currently unsure as to the impacts this will have in an environment that we wish to stay non-blocking.