Symfony – In Plain English

For every newcomer, Symfony appears to be an invincible beast at first glance. But taking a look from the distance reveals some patterns that are quite easy to grasp. We'll take a look at Symfony's concepts and philosophy, its components, the full-stack framework and the ecosystem. In a nutshell, this talk teaches you on a beginner's level what all the Symfony fuss is about and why it became *the* top-notch PHP project it is nowadays.

http://dcmuc16.drupalcamp.de/sessions/symfony-plain-english

Transcript

1. @bicpi Symfony – In Plain English Philipp Rieber #DCMuc16
2. #DCMuc16
3. #DCMuc16
4. @bicpi PHP・Symfony・DevOps・Technical Writer https://philipp-rieber.net #DCMuc16
5. @bicpi PHP・Symfony・DevOps・Technical Writer https://philipp-rieber.net #DCMuc16
6. ottonova.de We are creating a better private health insurance company for you. #DCMuc16
7. @sfugmuc Symfony User Group Munich #DCMuc16
8. First, Symfony2 is a reusable set of standalone, decoupled, and cohesive PHP components that solve common web development problems. – Fabien Potencier ‘ http://fabien.potencier.org/what-is-symfony2.html What is Symfony? #DCMuc16
9. BrowserKit ClassLoader Config Asset Console CssSelector Debug DependencyInjection DomCrawler EventDispatcher ExpressionLanguage Filesystem Finder Form Guard HttpFoundation HttpKernel Icu Intl Ldap Locale OptionsResolver Process PropertyAccess PropertyInfo Routing Security Serializer Stopwatch Templating Translation Validator VarDumper Yaml Guard Workflow #DCMuc16
10. BrowserKit ClassLoader Config Asset Console CssSelector Debug DependencyInjection DomCrawler EventDispatcher ExpressionLanguage Filesystem Finder Form Guard HttpFoundation HttpKernel Icu Intl Ldap Locale OptionsResolver Process PropertyAccess PropertyInfo Routing Security Serializer Stopwatch Templating Translation Validator VarDumper Yaml Guard Workflow #DCMuc16
11. $ composer require symfony/yaml Yaml Component #DCMuc16
12. $ composer require symfony/yaml require 'vendor/autoload.php'; Yaml Component #DCMuc16
13. $ composer require symfony/yaml require 'vendor/autoload.php'; use Symfony\Component\Yaml\Yaml; Yaml Component #DCMuc16
14. $ composer require symfony/yaml require 'vendor/autoload.php'; use Symfony\Component\Yaml\Yaml; $yaml = <<<YAML parameters: user: symfony pass: awesome YAML; Yaml Component #DCMuc16
15. $ composer require symfony/yaml require 'vendor/autoload.php'; use Symfony\Component\Yaml\Yaml; $yaml = <<<YAML parameters: user: symfony pass: awesome YAML; $config = Yaml::parse($yaml); Yaml Component #DCMuc16
16. $ composer require symfony/yaml require 'vendor/autoload.php'; use Symfony\Component\Yaml\Yaml; $yaml = <<<YAML parameters: user: symfony pass: awesome YAML; $config = Yaml::parse($yaml); // ['parameters' => ['user' => 'symfony', 'pass' => 'awesome']] Yaml Component #DCMuc16
17. BrowserKit ClassLoader Config Asset Console CssSelector Debug DependencyInjection DomCrawler EventDispatcher ExpressionLanguage Filesystem Finder Form Guard HttpFoundation HttpKernel Icu Intl Ldap Locale OptionsResolver Process PropertyAccess PropertyInfo Routing Security Serializer Stopwatch Templating Translation Validator VarDumper Yaml Guard Workflow #DCMuc16
18. $ composer require symfony/finder Finder Component #DCMuc16
19. $ composer require symfony/finder Finder Component require 'vendor/autoload.php'; use Symfony\Component\Finder\Finder; #DCMuc16
20. $ composer require symfony/finder Finder Component require 'vendor/autoload.php'; use Symfony\Component\Finder\Finder; $finder = Finder::create(); #DCMuc16
21. $ composer require symfony/finder Finder Component require 'vendor/autoload.php'; use Symfony\Component\Finder\Finder; $finder = Finder::create() ->in('/Users/bicpi/photos');
 #DCMuc16
22. $ composer require symfony/finder Finder Component require 'vendor/autoload.php'; use Symfony\Component\Finder\Finder; $finder = Finder::create() ->in('/Users/bicpi/photos') ->files();
 #DCMuc16
23. $ composer require symfony/finder Finder Component require 'vendor/autoload.php'; use Symfony\Component\Finder\Finder; $finder = Finder::create() ->in('/Users/bicpi/photos') ->files() ->name('*.jpg');
 #DCMuc16
24. $ composer require symfony/finder Finder Component require 'vendor/autoload.php'; use Symfony\Component\Finder\Finder; $finder = Finder::create() ->in('/Users/bicpi/photos') ->files() ->name('*.jpg') ->size('>= 1M'); #DCMuc16
25. $ composer require symfony/finder Finder Component require 'vendor/autoload.php'; use Symfony\Component\Finder\Finder; $finder = Finder::create() ->in('/Users/bicpi/photos') ->files() ->name('*.jpg') ->size('>= 1M'); foreach ($finder as $file) { echo $file->getFilename() . "\n"; } #DCMuc16
26. Do one thing. 
 Make it excellent. 
 Stay out of the way. – Unix Philosophy ‘ #DCMuc16
27. • … • Console Command Line Interface • Filesystem Basic utilities for the filesystem • Translation Tools for internationalisation • … #DCMuc16
28. Then, based on these components, Symfony2 is also a full-stack web framework. – Fabien Potencier ‘ http://fabien.potencier.org/what-is-symfony2.html What ELSE is Symfony? #DCMuc16
29. BrowserKit ClassLoader Config Asset Console CssSelector Debug DependencyInjection DomCrawler EventDispatcher ExpressionLanguage Filesystem Finder Form Guard HttpFoundation HttpKernel Icu Intl Ldap Locale OptionsResolver Process PropertyAccess PropertyInfo Routing Security Serializer Stopwatch Templating Translation Validator VarDumper Yaml Guard Workflow Your Application #DCMuc16
30. ☺ #DCMuc16
31. Request ☺ 1 #DCMuc16
32. Request ☺ Response 2 1 #DCMuc16 ?
33. Request ☺ Response 2 3 #DCMuc16 1 ?
34. Request ☺ Symfony full-stack Response #DCMuc16 1 2 3
35. It is all about transforming a Request into a Response #DCMuc16
36. HttpFoundation\Request
 HTTP Header, $_GET, $_POST, $_COOKIE, $_SESSION, $_SERVER
 #DCMuc16
37. HttpFoundation\Request
 HTTP Header, $_GET, $_POST, $_COOKIE, $_SESSION, $_SERVER
 HttpKernel
 Web framework core, “Glues” the components,
 Loads configuration and “Bundles”, Controls flow, Event Driven #DCMuc16
38. HttpFoundation\Request
 HTTP Header, $_GET, $_POST, $_COOKIE, $_SESSION, $_SERVER
 HttpFoundation\Response
 HTTP Status Code, HTTP Header, Content (HTML, JSON …) HttpKernel
 Web framework core, “Glues” the components,
 Loads configuration and “Bundles”, Controls flow, Event Driven #DCMuc16
39. HTTP specification #DCMuc16
40. #DCMuc16 Code please.
41. Request
 /blog/article?id=34 #DCMuc16
42. Request
 /blog/article?id=34 class BlogController extends Controller { 
 
 
 
 
 
 
 } #DCMuc16
43. Request
 /blog/article?id=34 class BlogController extends Controller { /** * @Route("/blog/article") */ public function articleAction(Request $request) { 
 
 
 
 
 
 
 } } #DCMuc16
44. Request
 /blog/article?id=34 class BlogController extends Controller { /** * @Route("/blog/article") */ public function articleAction(Request $request) { 
 
 
 
 
 
 
 } } #DCMuc16
45. Request
 /blog/article?id=34 class BlogController extends Controller { /** * @Route("/blog/article") */ public function articleAction(Request $request) { $id = $request->query->get('id'); 
 
 
 
 
 
 } } #DCMuc16
46. Request
 /blog/article?id=34 class BlogController extends Controller { /** * @Route("/blog/article") */ public function articleAction(Request $request) { $id = $request->query->get('id'); $article = $database->findArticle($id); 
 
 
 
 
 } } #DCMuc16
47. Request
 /blog/article?id=34 class BlogController extends Controller { /** * @Route("/blog/article") */ public function articleAction(Request $request) { $id = $request->query->get('id'); $article = $database->findArticle($id); if (!$article) { return new Response('Article not found.', 404); } 
 
 
 } } #DCMuc16
48. Request
 /blog/article?id=34 class BlogController extends Controller { /** * @Route("/blog/article") */ public function articleAction(Request $request) { $id = $request->query->get('id'); $article = $database->findArticle($id); if (!$article) { return new Response('Article not found.', 404); } 
 
 
 } } #DCMuc16 Response 404
 <html>Article not found</html>
49. Request
 /blog/article?id=34 class BlogController extends Controller { /** * @Route("/blog/article") */ public function articleAction(Request $request) { $id = $request->query->get('id'); $article = $database->findArticle($id); if (!$article) { return new Response('Article not found.', 404); } $html = $view->renderArticle($article); } } #DCMuc16
50. Request
 /blog/article?id=34 class BlogController extends Controller { /** * @Route("/blog/article") */ public function articleAction(Request $request) { $id = $request->query->get('id'); $article = $database->findArticle($id); if (!$article) { return new Response('Article not found.', 404); } $html = $view->renderArticle($article); return new Response($html, 200); } } #DCMuc16 Response 200
 <html>Article 34</html>
51. During the Request ➾ Response flow,
 many more components will assist #DCMuc16
52. • Routing Match URL to controller action • Templating Render templates • Security Decide about access • Config Load configuration • Forms Create HTML forms • … #DCMuc16
53. Who is going to configure all this?
54. Symfony Configuration #DCMuc16
55. Symfony Configuration dev prod test #DCMuc16
56. Symfony Configuration dev /app_dev.php/articles /app.php/articles prod test UseCaseTest #DCMuc16
57. Front Controller Symfony Configuration dev /app_dev.php/articles /app.php/articles prod test UseCaseTest #DCMuc16
58. Symfony Configuration dev /app_dev.php/articles /app.php/articles prod test UseCaseTest Test class #DCMuc16
59. Symfony Configuration dev /app_dev.php/articles /app.php/articles new AppKernel('prod', false); new AppKernel('dev', true); new AppKernel('test', false); prod test UseCaseTest #DCMuc16
60. Symfony Configuration dev /app_dev.php/articles /app.php/articles new AppKernel('prod', false); new AppKernel('dev', true); new AppKernel('test', false); config_prod.yml config_test.yml config_dev.yml prod test UseCaseTest #DCMuc16
61. Symfony Configuration dev /app_dev.php/articles /app.php/articles new AppKernel('prod', false); new AppKernel('dev', true); new AppKernel('test', false); config_prod.yml config_test.yml config_dev.yml prod test config.yml UseCaseTest #DCMuc16
62. database:
 driver: pdo_mysql
 charset: utf8
 
 
 
 # … config.yml #DCMuc16
63. 
 database:
 driver: pdo_mysql
 charset: utf8
 user: '%db_user%' password: '%db_password%'
 
 # … config.yml #DCMuc16
64. imports: - { resource: parameters.yml } database:
 driver: pdo_mysql
 charset: utf8
 user: '%db_user%' password: '%db_password%'
 
 # … config.yml #DCMuc16
65. imports: - { resource: parameters.yml } database:
 driver: pdo_mysql
 charset: utf8
 user: '%db_user%' password: '%db_password%'
 
 # … config.yml parameters.yml parameters:
 
 
 
 
 
 #DCMuc16
66. imports: - { resource: parameters.yml } database:
 driver: pdo_mysql
 charset: utf8
 user: '%db_user%' password: '%db_password%'
 
 # … config.yml parameters.yml parameters:
 
 
 
 
 
 added to .gitgnore #DCMuc16
67. imports: - { resource: parameters.yml } database:
 driver: pdo_mysql
 charset: utf8
 user: '%db_user%' password: '%db_password%'
 
 # … config.yml parameters.yml parameters:
 
 
 
 
 
 db_user: drupal db_password: ThisIsSuperS3cr3t
 
 # … added to .gitgnore #DCMuc16
68. Dependency Injection #DCMuc16
69. Logger Beispiel /** * @Route("/weather/at/{zip}") */ public function weatherAction(string $zip) { } #DCMuc16
70. Logger Beispiel /** * @Route("/weather/at/{zip}") */ public function weatherAction(string $zip) { // ...
 // ... Do heavy stuff to calculate $weatherData from $zip ... // ...
 $theWeather = $this->render('weather.html.twig', $weatherData); return new Response($theWeather, 200)); } #DCMuc16 Lots of stuff happens here to prepare the weather data
71. Logger Beispiel Let’s extract this to an independent service class! class WeatherForecast { public function forZip(string $zip): array { // ... // ... Do heavy stuff to calculate $weatherData from $zip ...
 // ... return $weatherData; } } #DCMuc16
72. Logger Beispiel class WeatherForecast { public function forZip(string $zip): array { // ... // ... Do heavy stuff to calculate $weatherData from $zip ...
 // ... return $weatherData; } } #DCMuc16 It only does ONE thing!
73. Logger Beispiel /** * @Route("/weather/at/{zip}") */ public function weatherAction(string $zip) { $weatherForecast = new WeatherForecast(); $weatherData = $weatherForecast->forZip($zip); $theWeather = $this->render('weather.html.twig', $weatherData); return new Response($theWeather, 200)); } Then use the service from the controller! #DCMuc16
74. Logger Beispiel class WeatherForecast { public function forZip(string $zip): array { $logger = new FileLogger('/var/log/weather.log'); // ... // ... Things might go wrong ...
 $logger->notice('No forecast found for ZIP '.$zip);
 // ... Things might work
 $logger->info('Forecast provided for ZIP '.$zip); // ... return $weatherData; } } But now imagine a dependency to a Logger service #DCMuc16
75. Logger Beispiel class WeatherForecast { public function forZip(string $zip): array { $logger = new FileLogger('/var/log/weather.log'); // ... // ... Things might go wrong ...
 $logger->notice('No forecast found for ZIP '.$zip);
 // ... Things might work
 $logger->info('Forecast provided for ZIP '.$zip); // ... return $weatherData; } } But now imagine a dependency to a Logger service #DCMuc16 • How to test this code? • How to switch the log file? • How to use a different logger?
76. Logger Beispiel class WeatherForecast
 { private $logger; public function __construct($logger)
 { $this->logger = $logger; } public function forZip(string $zip): array 
 { // ... $this->logger->info('Forecast provided for ZIP '.$zip); // ... } } Why not inject the logger dependency? #DCMuc16
77. Logger Beispiel class WeatherForecast
 { private $logger; public function __construct(Psr\Log\LoggerInterface $logger)
 { $this->logger = $logger; } public function forZip(string $zip): array 
 { // ... $this->logger->info('Forecast provided for ZIP '.$zip); // ... } } And type hint it against an interface contract? #DCMuc16
78. Logger Beispiel class FileLogger implements Psr\Log\LoggerInterface
 {
 
 private $logFilePath; public function __construct(string $logFilePath)
 { $this->logFilePath = $logFilePath; } public function notice($message) { … }
 public function info($message) { … }
 
 … } #DCMuc16
79. Logger Beispiel /** * @Route("/weather/at/{zip}") */ public function weatherAction(string $zip) { $logger = new FileLogger('/var/log/weather.log');
 $weatherForecast = new WeatherForecast($logger);
 // ... } Inject the logger dependency into the constructor #DCMuc16
80. #DCMuc16 Service Container
81. services:
 config.yml #DCMuc16 Now shift the service creation to a service container
82. services:
 logger:
 class: FileLogger
 
 
 
 config.yml #DCMuc16
83. services:
 logger:
 class: FileLogger
 arguments:
 - '/var/log/weather.log' 
 
 
 config.yml #DCMuc16
84. services:
 logger:
 class: FileLogger
 arguments:
 - '/var/log/weather.log' weather_forecast:
 class: WeatherForecast
 config.yml #DCMuc16
85. services:
 logger:
 class: FileLogger
 arguments:
 - '/var/log/weather.log' weather_forecast:
 class: WeatherForecast
 arguments:
 - '@logger' config.yml #DCMuc16
86. /** * @Route("/weather/at/{zip}") */ public function weatherAction(string $zip) { $weatherForecast = $this->container->get('...'); $weatherData = $weatherForecast->forZip($zip); $theWeather = $this->render('weather.html.twig', $weatherData); return new Response($theWeather, 200)); } #DCMuc16
87. /** * @Route("/weather/at/{zip}") */ public function weatherAction(string $zip) { $weatherForecast = $this->container->get('weather_forecast'); $weatherData = $weatherForecast->forZip($zip); $theWeather = $this->render('weather.html.twig', $weatherData); return new Response($theWeather, 200)); } #DCMuc16
88. config.yml #DCMuc16 services:
 logger:
 class: NullLogger weather_forecast:
 class: WeatherForecast
 arguments:
 - '@logger'
 

89. config.yml #DCMuc16 services:
 logger:
 class: DatabaseLogger weather_forecast:
 class: WeatherForecast
 arguments:
 - '@logger'
 

90. #DCMuc16 Console
91. File upload script with some flags, options and arguments #DCMuc16 $ ./upload-files --overwrite cat-1.jpg cat-2.jpg cat-3.jpg 

92. File upload script with some flags, options and arguments #DCMuc16 $ ./upload-files --overwrite cat-1.jpg cat-2.jpg cat-3.jpg 
 Uploading 'cat-1.jpg' ...

93. File upload script with some flags, options and arguments #DCMuc16 $ ./upload-files --overwrite cat-1.jpg cat-2.jpg cat-3.jpg 
 Uploading 'cat-1.jpg' ...
 Uploading 'cat-2.jpg' ...

94. File upload script with some flags, options and arguments #DCMuc16 $ ./upload-files --overwrite cat-1.jpg cat-2.jpg cat-3.jpg 
 Uploading 'cat-1.jpg' ...
 Uploading 'cat-2.jpg' ...
 Uploading 'cat-3.jpg' ...
95. #DCMuc16 Now we gonna tackle $_SERVER['argv'] !
96. use Symfony\Component\Console\Command\Command; 
 class UploadFilesCommand extends Command { } #DCMuc16 #DCMuc16
97. use Symfony\Component\Console\Command\Command; 
 class UploadFilesCommand extends Command { protected function configure() { // ... } } #DCMuc16
98. use Symfony\Component\Console\Command\Command; use Symfony\Component\Console\Input\InputInterface; use Symfony\Component\Console\Output\OutputInterface; class UploadFilesCommand extends Command { protected function configure() { // ... } protected function execute(InputInterface $input, OutputInterface $output) { // ... } } #DCMuc16
99. class UploadFilesCommand extends Command { protected function configure() { 
 } protected function execute(InputInterface $input, OutputInterface $output) { } } #DCMuc16
100. class UploadFilesCommand extends Command { protected function configure() { $this
 ->setName('upload-files');
 } protected function execute(InputInterface $input, OutputInterface $output) { } } #DCMuc16
101. class UploadFilesCommand extends Command { protected function configure() { $this
 ->setName('upload-files') ->addOption('overwrite', 'o', InputOption:: VALUE_NONE, 'Overwrite files?'); } protected function execute(InputInterface $input, OutputInterface $output) { } } #DCMuc16
102. class UploadFilesCommand extends Command { protected function configure() { $this ->setName('upload-files') ->addOption('overwrite', 'o', InputOption:: VALUE_NONE, 'Overwrite files?') ->addArgument('filePaths', InputArgument::IS_ARRAY, 'Files to upload?'); } protected function execute(InputInterface $input, OutputInterface $output) { 
 } } #DCMuc16
103. class UploadFilesCommand extends Command { protected function configure() { $this
 ->setName('upload-files') ->addOption('overwrite', 'o', InputOption:: VALUE_NONE, 'Overwrite files?') ->addArgument('filePaths', InputArgument::IS_ARRAY, 'Files to upload?'); } protected function execute(InputInterface $input, OutputInterface $output) { } } #DCMuc16
104. class UploadFilesCommand extends Command { protected function configure() { $this
 ->setName('upload-files') ->addOption('overwrite', 'o', InputOption:: VALUE_NONE, 'Overwrite files?') ->addArgument('filePaths', InputArgument::IS_ARRAY, 'Files to upload?'); } protected function execute(InputInterface $input, OutputInterface $output) { $overwrite = $input->hasOption('overwrite'); } } #DCMuc16
105. class UploadFilesCommand extends Command { protected function configure() { $this
 ->setName('upload-files') ->addOption('overwrite', 'o', InputOption:: VALUE_NONE, 'Overwrite files?') ->addArgument('filePaths', InputArgument::IS_ARRAY, 'Files to upload?'); } protected function execute(InputInterface $input, OutputInterface $output) { $overwrite = $input->hasOption('overwrite'); foreach ($input->getArgument('filePaths') as $path) { } } } #DCMuc16
106. class UploadFilesCommand extends Command { protected function configure() { $this
 ->setName('upload-files') ->addOption('overwrite', 'o', InputOption:: VALUE_NONE, 'Overwrite files?') ->addArgument('filePaths', InputArgument::IS_ARRAY, 'Files to upload?'); } protected function execute(InputInterface $input, OutputInterface $output) { $overwrite = $input->hasOption('overwrite'); foreach ($input->getArgument('filePaths') as $path) { $output->writeLn("Uploading '{$path}' ... "); // ... do the upload depending on $overwrite } } } #DCMuc16
107. Anything else? #DCMuc16
108. Bundles • ~ PlugIns, but even better • Everything in Symfony Full-Stack is a Bundle • Yes, Symfony Full-Stack itself is a Bundle • Core and custom code is in Bundles • Registered in HttpKernel #DCMuc16
109. • PSR – PHP Standards Recommendations • HTTP Specification Symfony ♥ Standards #DCMuc16
110. • Git & GitHub • Semantic Versioning – Breaking.Feature.Fix • Dependency Injection • Event Driven • Popularize ORMs • New level of code quality and architecture • Command Line Tools Symfony drives Innovation … just to name a few (in the PHP world, at least …) #DCMuc16
111. • Twig • Composer • Monolog • Swiftmailer • Silex • PHP CS Fixer
 … Symfony “by-products” #DCMuc16
112. • Outstanding Documentation • Huge ecosystem of 3rd-party bundles • Creates many “celebrities” • Conferences • Certification Symfony’s Community (and SensioLabs) #DCMuc16
113. Evolution, not Revolution Symfony 3 #DCMuc16
114. @bicpi Questions? https://philipp-rieber.net #DCMuc16
115. Links • http://symfony.com/ • https://github.com/symfony • http://fabien.potencier.org/what-is-symfony2.html • http://symfony.com/doc/current/create_framework • http://www.php-fig.org/ #DCMuc16