The document details a presentation by Jakub Zalas at a UK Symfony meetup in November 2012, focusing on best practices for Symfony development, including code bundling, event listeners, and maintaining code quality. It emphasizes the importance of understanding Symfony's architecture and making use of its features, such as data transformers and Twig extensions, to improve clarity and efficiency in web applications. Additionally, it discusses debugging techniques and the use of the service container for cleaner implementations.

1. UK Symfony Meetup
November, 2012
Symfony
War Stories
Jakub Zalas
SensioLabsUK
http://www.rgbstock.com/bigphoto/mhY2DCY

2. Jakub Zalas a.k.a. Kuba
○ Remembers symfony 1.0
(2007)
○ Open Source contributor
○ BDD advocate
○ Works at Sensio Labs UK
○ ZCE & Sensio Labs ○ Twitter: @jakub_zalas
Certified Symfony ○ Blog: http://zalas.eu
Developer ○ Github: @jakzal

3. Symfony War Stories
● Bundling the code
● Thinking outside of the bundle
● Being lazy
● Learning your stuff
● Keeping your playground clean
● Building the quality in

4. Bundling
the code
http://www.rgbstock.com/bigphoto/mfXkYUq

5. VS

6. Whenever in doubt...
● Start simple and let the design emerge
● Extract bundles when you need to reuse it
or you see it would improve clarity
● Avoid two-way dependencies between
bundles

7. Thinking
outside of
the bundle
http://www.rgbstock.com/bigphoto/mfBYR2S

8. VS

9. To keep your design clean...
● Treat bundles as an integration layer
between PHP libraries and the Symfony
framework
● In your libraries, avoid dependencies on
bundles

10. Being lazy
http://www.sxc.hu/photo/858871

11. There's a bundle for that!

12. Learning
your stuff
http://www.sxc.hu/photo/1095604

13. Have you ever used?
● Event listeners and subscribers
● Form data transformers
● Twig extensions
● Profiler extensions
● DIC compiler passes
● more...

14. It's easy!
let's see few examples...

15. Event listeners and subscribers (Doctrine)
services:
sensio.listener.search_indexer:
class: SensioListenerSearchIndexer
tags:
-
name: doctrine.event_listener
event: postPersist

16. namespace SensioListener;
use DoctrineORMEventLifecycleEventArgs;
use SensioEntityProduct;
class SearchIndexer
{
public function postPersist(LifecycleEventArgs $args)
{
$entity = $args->getEntity();
$entityManager = $args->getEntityManager();
if ($entity instanceof Product) { /* Index me */ }
}
}

17. Lifecycle callbacks (Doctrine)
/**
* @ORMEntity()
* @ORMHasLifecycleCallbacks()
*/
class User
{
/**
* @ORMPrePersist
*/
public function updateCreatedAt() { /* ... */ }
}

18. Event listeners and subscribers (Symfony)
services:
sensio.action_listener:
class: SensioMyBundleEventListenerMyListener
tags:
-
name: kernel.event_listener
event: kernel.controller
method: onKernelController

19. namespace SensioMyBundleEventListener;
class MyListener
{
public function onKernelController(
FilterControllerEvent $event)
{
$controller = $event->getController();
$request = $event->getRequest();
// ...
}
}

20. Event listeners and subscribers (Forms)
$callback = function(FormEvent $event) {
if (null === $event->getData()) {
$formData = $event->getForm()->getData();
$event->setData($formData);
}
};
$builder->add('email', 'text');
$builder->get('email')
->addEventListener(
FormEvents::PRE_BIND, $callback
);

21. Data transformers (Forms)
class IssueToNumberTransformer
implements DataTransformerInterface
{
public function transform($issue)
{
// return issue number
}
public function reverseTransform($number)
{
// return Issue instance
}
}

22. $field = $builder->create('issue', 'text')
->addModelTransformer(new IssueToNumberTransformer());
$builder->add($field);

23. Twig extensions
<!-- Instead of: -->
<div class="price">
${{ 9800.333|number_format(2, '.', ',') }}
</div>
<!-- just do: -->
<div class="price">
{{ 9800.333|price }}
</div>

24. class SensioExtension extends Twig_Extension
{
public function getFilters()
{
return array(
'price' => new Twig_Filter_Method(
$this, 'priceFilter')
);
}
public function getName()
{
return 'sensio_extension';
}
public function priceFilter($number, /* ... */ ) {}
}

25. public function priceFilter(
$number, $decimals = 0, $decPoint = '.', $sep = ',')
{
$price = number_format(
$number, $decimals, $decPoint, $sep
);
return '$'.$price;
}

26. services:
sensio.twig.acme_extension:
class: SensioTwigSensioExtension
tags:
- { name: twig.extension }

27. Web profiler

28. Debugging commands
./app/console container:debug
./app/console container:debug twig.loader
./app/console router:debug
./app/console router:debug homepage
./app/console router:match /logout

29. Debugging commands

30. http://www.rgbstock.com/bigphoto/mZTKnw6
Keeping your playground clean

31. Use the service container!

32. public function publishAction($date)
{
$show = $this->findShow($date);
$fileName = sprintf('show-%s.json', $date->format('Y-m-d'));
while (file_exists($fileName)) {
$fileName = $fileName.preg_replace('/.json$/', '-1.json');
}
$options = array( /* options here */ );
$s3 = new AmazonS3($options);
$objectOptions = array(
'body' => json_encode($show), 'acl' => $options['objectAcl']);
if (!$s3->create_object('my-bucket', $fileName, $objectOptions) {
throw new Exception('Could not save file');
}
// ...
}

33. public function publishAction($date)
{
$show = $this->findShow($date);
$fileNameResolver = new FileNameResolver();
$filesystem = $this->get('gafrette_filesystem');
$publisher = new Publisher(
$fileNameResolver, $filesystem
);
$publisher->publish($show, $date);
}

34. Use the service container!
public function publishAction($date)
{
$show = $this->findShow($date);
$publisher = $this->get('sensio.publisher');
$publisher->publish($show, $date);
}

35. Be SOLID!

36. /**
* @ORMEntity()
*/
class Product
{
// ...
public function createOrderReport($month)
{
// $this->em->getRepository() ...
}
public function setEntityManager($em)
{
$this->em = $em;
}
}

37. class OrderReportGenerator
{
private $em = null;
public function __construct(EntityManager $em)
{
$this->em = $em;
}
public function generate(Product $product, $month)
{
// ...
}
}

38. Building quality in
http://www.rgbstock.com/photo/nrcyovQ/perfect

39. Unit tests
class ReportTest extends PHPUnit_Framework_TestCase
{
public function testThatItReturnsFilePath()
{
$report = new Report();
$file = $report->create('January');
$this->assertSame('/january.csv', $file);
}
}

40. ... or specs
namespace spec;
class Report extends PHPSpec2ObjectBehavior
{
function it_returns_file_path()
{
$this->create('January')
->shouldReturn('/january.csv');
}
}

41. Managing expectations
Feature: Viewing recent news on the homepage
As a Marketing Manager
I want Visitors to see recent news on the homepage
In order to get them interested in the content
Scenario: Viewing recent news
Given there are 10 news items
And there were 5 news items written since yesterday
When I visit the homepage
Then I should see 5 recent news items in the news section
Scenario: There is not enough news
Given there are 10 news items
But there were 3 news items written since yesterday
When I visit the homepage
Then I should see 3 recent news items in the news section

42. Thank you!