Mission (Im)possible: Quality Decoupled Code with Drupal 7

We're all excited about Drupal 8 coming up soon and we want to be ready for it! How can we make sure our code is ready for it? How can we build modules that are backwards compatible with D7 and future proofed for D8?

Learn how to build code decoupled from your platform and use it with Drupal or any other framework.

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1. Marek Matulka
2. at @super_marek
6. http://photobucket.com/user/marcrobinsone/media/Drupal%20Comics/marcrobinsonegmailcom__drupalNinja.png.html
9. In order to create a good software, you have to know what the software is all about. – Eric Evans
10. How do we learn?
11. Stakeholders
12. Ask for examples... ...write stories!
13. Vocabulary
14. Ubiquitous Language Ubiquitous Language
15. Ubiquitous Language Ubiquitous Language Domain Expert Analyst Tester Developer Developer
16. Ubiquitous Language Ubiquitous Language Domain Expert Analyst Tester Developer Developer Application Code Acceptance Criteria Specs and documentation
17. Example?
18. Example Feature: In order to see correct prices As a visitor I need to be able to locate the nearest depot Scenario: Given I am visiting a product page for the first time And I got prompted to locate my nearest depot When I enter my post code Then I should see my local depot information
19. Example Feature: In order to see correct prices As a visitor I need to be able to locate the nearest depot Scenario: Given I am visiting a product page for the first time And I got prompted to locate my nearest depot When I enter my post code Then I should see my local depot information
20. Domain namespace Acme\Depot; interface DepotLocator { /** * @param string $postcode * * @return Depot */ public function locateDepot($postcode); }
21. Implementation namespace Acme\MagentoAdapter; use Acme\Depot\DepotLocator; class MagentoDepotLocator implements DepotLocator { public function locateDepot($postcode) { return $this->entityMapper->mapDepot( $this->clientAdapter->findDepotByPostcode($postcode) );
22. why interface?
23. Layered Architecture “High level modules should not depend on lower level implementation” – Robert C. Martin User Interface Application Domain Infrastructure
24. Dependency Inversion Policy Layer <interface> Policy Service Mechanism Layer <interface> Mechanism Service Utility Layer
25. Layered Architecture User Interface Application Domain Infrastructure
26. Layered Architecture User Interface Application Domain Infrastructure
27. Clean Architecture Entities Use Cases Controllers Web
28. Clean Architecture Entities Use Cases Controllers Web Framework Drivers Interface Adapters Application Business Rules Enterprise Business Rules
29. Hexagonal Architecture UI Adapter Log Adapter Data Storage Adapter External Data Adapter Application Domain
30. Hexagonal Architecture Acme\Depot\DepotLocator Acme\MagentoAdapter\MagentoDepotLocator
31. Hexagonal Architecture Acme\Depot\DepotLocator Acme\MagentoAdapter\MagentoDepotLocator port adapter
32. Why clean architecture?
33. Why clean architecture? - your code is clean(er) - decoupled from framework - reusable - easy to test - easy to maintain - easy to change
36. symfony/dependency-injection symfony/config dependency injection
37. Dependency Injection - a standardised and centralised way of constructing objects in our application
38. Kernel public function boot() { $this->container = new ContainerBuilder(); $this->container->compile(); }
39. Kernel public function boot() { $this->container = new ContainerBuilder(); $loader = new YamlFileLoader($this->container, new FileLocator('app/config')); $loader->load('parameters.yml'); $this->container->compile(); }
40. Kernel public function boot() { $this->container = new ContainerBuilder(); $loader = new YamlFileLoader($this->container, new FileLocator('app/config')); $loader->load('parameters.yml'); $loader = new XmlFileLoader($this->container, new FileLocator('app/config')); $loader->load('services.xml'); $this->container->compile(); }
41. Kernel public function boot() { $this->container = new ContainerBuilder(); $loader = new YamlFileLoader($this->container, new FileLocator('app/config')); $loader->load('parameters.yml'); $loader = new XmlFileLoader($this->container, new FileLocator('app/config')); $loader->load('services.xml'); $this->container->registerExtension(new ApplicationExtension()); $this->container->compile(); }
42. Kernel public function boot() { $this->container = $this->buildContainer(); } /** * @return ContainerBuilder */ private function buildContainer() { $container = new ContainerBuilder(); $loader = new YamlFileLoader($container, new FileLocator('app/config')); $loader->load('parameters.yml'); $loader = new XmlFileLoader($container, new FileLocator('app/config')); $loader->load('services.xml'); $container->registerExtension(new ApplicationExtension()); $container->compile(); return $container; }
43. Kernel public function boot() { if (file_exists($this->cachedContainerFileName)) { require $this->cachedContainerFileName; $this->container = new ProjectServiceContainer(); } else { $container = $this->buildContainer(); $dumper = new PhpDumper($container); file_put_contents($this->cachedContainerFileName, $dumper->dump()); $this->container = $container; } }
44. Kernel public function boot() { if (file_exists($this->cachedContainerFileName)) { require $this->cachedContainerFileName; $this->container = new ProjectServiceContainer(); } else { $container = $this->buildContainer(); if ('dev' !== $container->getParameter('environment')) { $dumper = new PhpDumper($container); file_put_contents($this->cachedContainerFileName, $dumper->dump()); } $this->container = $container; } }
45. parameters.yml application: database: name: acme-dev username: acme-dev password: S0m3R4nD0mP455 host: localhost port: ~ soap_client: wsdl: https://api.store.local/v1/?wsdl http_auth_username: acme-dev http_auth_password: S0m3R4nD0mP455 username: acme-dev-user api_key: R4nD0mAp1K3y product_hydrator: product_url_snippet: http://store.local/product/{sku} product_image_url: http://store.local/media/catalog/product/uploads/
46. services.xml
47. symfony/console console commands
48. Import Handler class ImportAndPersistActionHandler { /** * @param ProductImporter $importer * @param ProductPersister $persister */ public function __construct(ProductImporter $importer, ProductPersister $persister) { $this->importer = $importer; $this->persister = $persister; } public function importAndPersistProducts() { $productsList = $this->importer->importProducts(); $this->persister->saveAll($productsList); } }
49. Console command class ImportAndPersistCommand extends Command { public function __construct(ImportAndPersistActionHandler $action) { $this->action = $action; parent::__construct(); } protected function configure() { $this->setName('products:import'); } protected function execute(InputInterface $input, OutputInterface $output) { $startTime = microtime(true); $this->action->importAndPersistProducts(); $output->writeln( sprintf("Products import completed in %1.02fs.", microtime(true) - $startTime) ); } }
50. app/console #!/usr/bin/php <?php require_once (__DIR__ . '/../vendor/autoload.php'); use Acme\Application\Kernel; use Symfony\Component\Console\Application; $kernel = new Kernel(); $kernel->boot(); $application = new Application(); $application->addCommands([ $kernel->getContainer()->get('acme.command.import_products'), $kernel->getContainer()->get('acme.command.delete_products'), $kernel->getContainer()->get('acme.command.depot_locate'), ]); $application->run();
51. symfony/filesystem persisting products
52. XML Writer class ProductXmlWriter implements ProductPersister { /** * @param Filesystem $filesystem * @param string $fileName */ public function __construct(Filesystem $filesystem, string $fileName) { $this->filesystem = $filesystem; $this->fileName = $fileName; } /** * @param ProductList $productList */ public function saveAll(ProductList $productList) { $this->filesystem->dumpFile($this->fileName, $this->renderXml($productList)); } }
53. Why write XML? - fetching data from Magento and dumping it into xml file is quick - xml can be imported by Drupal’s feed importer
54. Why it didn’t work? - Feed importer was damn slow - 10k products imported in 4.5h - Scheduling import with Elysia Cron module was flaky - Scheduled feed importer would add products all over again - resources hungry!
55. Direct save to the db class DatabaseProductPersister implements ProductPersister { private $repository; /** * @param ProductRepository $repository */ public function __construct(ProductRepository $repository) { $this->repository = $repository; } public function saveAll(ProductList $productList) { foreach ($productList as $product) { $this->repository->save($product); } } }
56. Why direct save to the db? - Drupal promises data structure won’t ever change - It’s fast - 40k products in 2 minutes - It works!
57. composer.json "require": { "php": ">=5.4.0", "symfony/console": "~2.5", "drush/drush": "7.*@dev", "symfony/finder": "~2.5", "symfony/dependency-injection": "~2.5", "symfony/config": "~2.5", "symfony/filesystem": "~2.6", "doctrine/dbal": "~2.5", "rhumsaa/uuid": "~2.8" },
58. container.php <?php require_once DRUPAL_ROOT . '/../vendor/autoload.php'; $kernel = new \Acme\Application\Kernel(); $kernel->boot(); variable_set('di_container', = $kernel->getContainer());
59. database.php $databases = [ 'default' => [ 'default' => [ 'database' => $conf['di_container']->getParameter('database.name'), 'username' => $conf['di_container']->getParameter('database.username'), 'password' => $conf['di_container']->getParameter('database.password'), 'host' => $conf['di_container']->getParameter('database.host'), 'port' => $conf['di_container']->getParameter('database.port'), 'driver' => 'mysql', 'prefix' => '', ], ], ];
60. settings.php <?php ... include_once 'config/container.php'; include 'database.php'; ...
61. depot_locator.module function get_depot_json($postcode) { global $conf; $depotEntity = variable_get('di_container') ->get('acme.depot_locator')->locateDepot($postcode); $depot = $depotEntity->toArray(); set_depot_cookies($depot); return ['depot' => $depot]; }
62. Project folder structure
65. as a CMS platform Drupal is great!
66. Cherry pick what you need! Symfony Components
67. Try it yourself! Decoupled code
68. Right tool Choose wisely!
70. https://joind.in/15624 @super_marek