By parallelizing and time-shifting when we do work we need to do to present a web page, we can speed up the response time so users experience a nice quick site and we can control the amount of load to smooth out traffic spikes.

1. Using Queues and
Offline Processing
David Stockton
Madison PHP - Oct 1, 2016

2. Synchronous
Processing

3. Shopping Trip

4. Car Wash

5. DMV

6. The Web Should
Be Fast

7. Customers Want It
To Be Fast

8. Think Work Order

9. Asynchronous
Processing

10. Real-World
Async

11. Online Shopping

12. Personal
Assistants

13. Personal
Assistants

14. Web Pages

15. Infinite Scrollers

16. Magical
Parallelization

17. Fake It
Until You Make It

18. Time Is
Not On Our Side

19. User Input

20. Do The Needful Now
Everything Else Can Wait

21. Database Queue

22. Data
Synchronization

23. Message
Queues

24. Work Producer

25. Work
Producer

26. How does that
help?

27. Workers

28. Workers

29. Multiplicity

30. Control Server
Load

31. Handle Load
Spikes

32. Workers as
Assistants

33. Ballottrax

34. Data Loads

35. Communication Rates
• Email - 250 connections, 10 per seco
• SMS - 30 per second
• Voice - 1 per second, per phone
number

36. Splitting Work By
Type

37. Rate Limiting

38. Queues to
Queue Work

39. Acceptable for
Work

40. Notification
Filters

41. Geocoding

42. Producers Consumers

43. DB Queue vs
Pure MQ

44. Feeding Queue from
Database - Cron

45. Feeding Queues from
Database - Polling

46. Polling -
The Worst

47. Events and
Webhooks

48. Magical
Webhooks

49. Automated Pull
Requests

50. Queues For
Webhooks

51. Install AMQPLib
composer require php-amqplib/
php-amqplib

52. Create Queue/Channel
$connection = new PhpAmqpLibConnection
AMQPStreamConnection($server, $port, $user,
$password, $vhost);
$channel = $connection->channel();
$channel->queue_declare(
$queueName,
false, // Passive
true, // Durable
false, // Exclusive
false // Auto Delete
);

53. Setting Channel Options
$channel->basic_qos(null, 1, null);
$channel->basic_consume(
$queueName,
'', // Consumer tag
false, // No local
false, // No ACK
false, // Exclusive
false, // No wait
$callback
);

54. Do Some Work
while (count($channel->callbacks)) {
$channel->wait();
}
$channel->close();
$connection->close();

55. The Callback
$callback = function ($msg) {
$message = (array) json_decode($msg-
>body, false);
// Do work
$msg->delivery_info['channel']
->basic_ack(
$msg->delivery_info['delivery_tag']
);
};

56. Creating a Message
$message = new PhpAmqpLibMessageAMQPMessage(
json_encode($data),
[
'delivery_mode' =>
AMQPMessage::DELIVERY_MODE_PERSISTENT
]
);

57. Putting Message in the Queue
try {
$channel->basic_publish($message, '',
$queueName);
} catch (AMQPExceptionInterface $e) {
$this->getLogger()->err(
'Error putting message into RabbitMQ',
$e->getMessage()
);
return false;
}

58. Work Priority

59. Recap

60. Questions?

61. David Stockton
@dstockto
https://davidstockton.com
https://tddftw.com