Asynchronous PHP

Florian Engelhardt

The Problem

The customers are waiting too long at the checkout

Stuff that happens during checkout

persist the order and modify stock
send tracking data to services
send order confirmation email
capture money from payment gateway

Summary

The customers are waiting for things they …

… don’t know about
… don’t care about

Disclaimer: If you have something that works for you, stick with it!

How RabbitMQ works

This is highly simplified 😉

Asynchronous Consumer

consume the messages from RabbitMQ
send tracking data to service via HTTP
non blocking / async
written in PHP

Why PHP?

Why don’t you just use Node.js?
— RandomUserAtStackoverflow

But really, why PHP?

has the native functionality to write async code
there are cool libraries doing the heavy lifting for you
these libs work on core php w/o extensions
you already understand it anyway

Disclaimer: It is still a good Idea to checkout a new language every now and then!

Let’s build something!

aka Demo time!

A fully working example on two slides!

Disclaimer: Please don’t!

The connection

$client = new \Bunny\Async\Client();
$browser = new \React\Http\Browser();

$app = ....

$client->connect()->then(function ($client) {
    return $client->channel();
})->then(function ($channel) use ($app) {
    // waiting for messages
    $channel->consume(
        $app,
        'hello'
    );
});

React\EventLoop\Loop::get()->run()

The App

$app = function ($message, $channel, $client) use ($browser) {
    $body = json_decode($message->content);
    $promises = [];
    foreach ($body->orderedItem as $orderedItem) {
        $promises[] = $browser->post(
            'https://httpbin.org/post',
            [],
            http_build_query([
                'sku' => $orderedItem->orderItemNumber,
                'amount' => $orderedItem->orderQuantity
            ])
        );
    }
    \React\Promise\all($promises)->then(
        function() use ($channel, $message) {
            $channel->ack($message);
        }
    );
};