Symfony2 Components. How not to reinvent the wheel.

WebConf Riga 2012, 10.11.2012
Evercode Talks №1, 08.11.2012
Don't reinvent the wheel, use the existing one, make them better, enjoy and don't waste your time. Symfony2 framework has a remarkable set of standalone decoupled components for various task of web development. Let's see how we can use them for our tasks.

1. Symfony2 Components. How not to reinvent the wheel. Roman Lapin, Evercode Lab @memphys, roma@evercodelab.com
3. Don’t Reinvent The Wheel, Unless You Plan on Learning More About Wheels. Jeff Atwood (http:/ /www.codinghorror.com/blog/2009/02/dont-reinvent-the-wheel-unless-you-plan-on-learning- more-about-wheels.html)
5. Symfony Components Beside being a full-stack framework, Symfony is also a set of decoupled and standalone components. Symfony Components implement common features needed to develop websites.
6. Reasons Decoupled and Standalone Highly tested Clean API Widely adopted Audited for security issues by an independent company There are people (great community)
7. Components ClassLoader Config DependencyInjection EventDispatcher HttpFoundation HttpKernel Routing Templating BrowserKit Process Console Finder CssSelector DomCrawler Form Locale Serializer Yaml Validator Translation
8. Components ClassLoader Config DependencyInjection EventDispatcher HttpFoundation HttpKernel Routing Templating BrowserKit Process Console Finder CssSelector DomCrawler Form Locale Serializer Yaml Validator Translation
9. Installation Git Pear Composer
10. Installation Git Pear Composer
11. Installation { "require": { "symfony/console": "2.1.*", "symfony/process": "2.1.*", "symfony/finder": "2.1.*", "symfony/form": "2.1.*", "symfony/validator": "2.1.*", "symfony/config": "2.1.*", "symfony/translation": "2.1.*", "symfony/security": "2.1.*" ... } } $ composer install require_once __DIR__.'/../vendor/autoload.php';
12. HttpFoundation The Symfony2 HttpFoundation component replaces these default PHP global variables and functions by an Object-Oriented layer.
13. HttpFoundation use Symfony\Component\HttpFoundation\Request; $request = Request::createFromGlobals(); $input = $request->get('name', 'World'); // the URI minus any query parameters $request->getPathInfo(); // retrieve SERVER variables $request->server->get('HTTP_HOST'); // retrieves an instance of UploadedFile identified by foo $request->files->get('foo');
14. HttpFoundation // COOKIE value $request->cookies->get('PHPSESSID'); // HTTP request header $request->headers->get('host'); $request->getMethod(); // GET, POST, PUT, DELETE, HEAD // simulate a request $request = Request::create('/awesome.php?say=wooohooo');
15. HttpFoundation use Symfony\Component\HttpFoundation\Response; $response = new Response(); $response->setContent(“What’s up, Doc?”); $response->setStatusCode(200); $response->headers->set('Content-Type', 'text/html'); // HTTP cache headers $response->setMaxAge(10);
16. Finder The Finder Component finds files and directories via an intuitive fluent interface.
17. Finder use Symfony\Component\Finder\Finder; $finder = new Finder(); $finder->files() ->in(__DIR__) ->in(__DIR__.'/../data') ->exclude('crap') ; foreach ($finder as $file) { print $file->getRealpath()."\n"; print $file->getFilename()."\n"; }
18. Finder // files or directories $finder->files(); $finder->directories(); $finder->files()->followLinks(); $finder->ignoreVCS(false); // sorting $finder->sortByName(); $finder->sortByType();
19. Finder // filtering $finder->files()->name('*.bugs'); $finder->files()->notName('*.bunny'); $finder->files()->contains('/ehhhh\s+what$/i'); $finder->files()->size('>= 1K')->size('<= 42K'); $finder->date('since yesterday'); $finder->depth('== 0');
20. Console The Console component allows you to create command-line commands. Your console commands can be used for any recurring task, such as cronjobs, imports, or other batch jobs.
21. Console #!/usr/bin/env php <?php use Symfony\Component\Console\Application; use App\Command\ParseCommand; $console = new Application(); $console->add(new ParseCommand()); $console->run();
22. Console
23. Console namespace App\Command; use Symfony\Component\Console\Command\Command; use Symfony\Component\Console\Input\InputArgument; use Symfony\Component\Console\Input\InputInterface; use Symfony\Component\Console\Input\InputOption; use Symfony\Component\Console\Output\OutputInterface;
24. Console class ParseCommand extends Command { protected function configure() { $this ->setName('parse') ->setDescription('Parses cached information') ->addArgument('date', InputArgument::OPTIONAL, "Put in some date.", date('Y-m-d')) ; } }
25. Console protected function execute(InputInterface $input, OutputInterface $output) { $date = $input->getArgument('date'); if (empty($date)) { $date = date('Y-m-d'); } $formatter = new CsvFormatter(); $formatter->process($date); $output->writeln('<info>operation finished</info>'); }
26. CssSelector The CssSelector Component converts CSS selectors to XPath expressions.
27. CssSelector use Symfony\Component\CssSelector\CssSelector; print CssSelector::toXPath('div.item > h4 > a'); descendant-or-self::div[contains(concat(' ',normalize- space(@class), ' '), ' item ')]/h4/a
28. CssSelector $document = new \DOMDocument(); $document->preserveWhiteSpace = false; $document->loadHTML($html); $xpath = new \DOMXPath($document); $blocks = $xpath->query( CssSelector::toXPath('div.filters ul li b a') );
29. DomCrawler The DomCrawler Component eases DOM navigation for HTML and XML documents.
30. DomCrawler $document = new \DOMDocument(); $document->preserveWhiteSpace = false; $document->loadHTML($html); $xpath = new \DOMXPath($document); $blocks = $xpath->query( CssSelector::toXPath('div.filters ul li b a') );
31. DomCrawler use Symfony\Component\DomCrawler\Crawler; use Symfony\Component\CssSelector\CssSelector; $crawler = new Crawler($html); $crawler = $crawler->filterXPath( CssSelector::toXPath('div.filters ul li b a') ); $crawler = $crawler->filter('div.filters ul li b a');
32. DomCrawler $crawler->filter('body > p')->first(); $crawler->filter('body > p')->last(); $crawler->filter('body > p')->siblings(); $crawler->filter('body > p')->nextAll(); $crawler->filter('body > p')->previousAll(); $crawler->filter('body')->children(); $crawler->filter('body > p')->parents();
33. DomCrawler $link = $crawler->selectLink('follow the rabbit')->link(); $uri = $link->getUri(); $form = $crawler->selectButton('validate')->form(); $form = $crawler->selectButton('validate')->form(array( 'name' => 'Just Bugs', )); $uri = $form->getUri();
34. DomCrawler use Goutte\Client; // make a real request to an external site $client = new Client(); $crawler = $client->request('GET', 'https://github.com/login'); // select the form and fill in some values $form = $crawler->selectButton('Log in')->form(); $form['login'] = 'rabbitcoder'; $form['password'] = 'Carrot123'; // submit that form $crawler = $client->submit($form);
35. Form Form provides tools for defining forms, rendering and binding request data to related models. Furthermore it provides integration with the Validation component.
36. Form namespace App\Form; use Symfony\Component\Form\AbstractType; use Symfony\Component\Form\FormBuilderInterface; use Symfony\Component\Validator\Constraints as Assert; use Symfony\Component\OptionsResolver\OptionsResolverInterface; class RegisterType extends AbstractType { ... public function getName() { return 'register'; } }
37. Form public function buildForm(FormBuilderInterface $builder, array $options) { $builder ->add('event', 'choice', array( 'choices' => $events, 'constraints' => new Assert\Choice(array_keys($events)), 'required' => true, 'attr' => array( 'class' => 'input-xlarge' ), )) ->add('first_name', 'text', array( 'constraints' => new Assert\NotBlank(), 'required' => true, )) }
38. Form $app->match('/', function (Request $request) use ($app) { $form = $app['form.factory']->create( new RegisterType($app['event_service']) ); if ('POST' == $request->getMethod()) { $form->bind($request); if ($form->isValid()) { $data = $form->getData(); // ... return $app->redirect('success'); } } return $app['twig']->render('index.html.twig', array( 'form' => $form->createView() )); });
39. Form <form action="/" method="post" novalidate> {{ form_widget(form) }} <input type="submit" name="submit" value="Submit" /> </form>
40. Security Security provides an infrastructure for sophisticated authorization systems, which makes it possible to easily separate the actual authorization logic from so called user providers that hold the users credentials.
41. Security $app->match('/admin', function (Request $request) use ($app) { return $app['twig']->render('admin.html.twig', array()); }) ->bind('admin');
42. Security $app->register(new Silex\Provider\SecurityServiceProvider()); $app['security.firewalls'] = array( 'admin' => array( 'pattern' => '^/admin', 'http' => true, 'users' => array( 'admin_login' => array( 'ROLE_ADMIN', 'encrypted_pass' ), ), ), );
43. Use cases? Refactoring New apps Integrating in existent code Inventing the wheel (yet another framework?) You name it!
44. Want more? Composer (http:/ /getcomposer.org/) Packagist (https:/ /packagist.org/) Silex (http:/ /silex.sensiolabs.org/) Twig (http:/ /twig.sensiolabs.org/) SwiftMailer (http:/ /swiftmailer.org/) KnpBundles (http:/ /knpbundles.com/)
45. Sources http:/ /symfony.com/components “Create your own framework... on top of the Symfony2 Components” by Fabien Potencier Source code http:/ /www.php-fig.org/
46. Reinvent away. Most of our current technology sucks, and even if it didn't, who am I to try and stop you? Bob Lee (http:/ /blog.crazybob.org/2007/09/why-reinvent-wheel.html)
47. We wanted flying cars— instead we got 140 characters. Peter Thiel
49. Thanks! Roma Lapin Evercode Lab roma@evercodelab.com @memphys