What’s a typical Symfony 4.2 application like?

Symfony's configuration system has improved a lot in recent years. Version 4.2 brings a lot of minor improvements that all together give an even better developer experience. Let's step back and look at how we can tackle all of the most common problems using the new approaches! This will include tricks for configuring services as easily as possible, handling different environment configuration and the hugely important topic of environment variables and secrets. Best of all, we'll discuss some strategies to migrate your existing apps so you're never going to be left behind.

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1. application like? What’s a typical
2. @nicolasgrekas
3. Stability and predictability are king!
4. A Symfony Application is built around a Runtime configurable compiled container @nicolasgrekas
5. SOLID principles @nicolasgrekas
6. reproducible-builds.org @nicolasgrekas
7. 12factor.net @nicolasgrekas
8. @nicolasgrekas Big, explicit YAML files Big, explicit XML files 3rd Party Bundles Our App
9. @nicolasgrekas <service id="twig" class="Twig\Environment" public="true"> <argument type="service" id="twig.loader" /> <argument /> <!-- Twig options --> <call method="addGlobal"> <argument>app</argument> <argument type="service" id="twig.app_variable" /> </call> <call method="addRuntimeLoader"> <argument type="service" id="twig.runtime_loader" /> </call> </service>
10. services: app.spooky_word_generator: class: App\SpookyWordGenerator app.halloween_costume_creator: class: App\HalloweenCostumeCreator arguments: ['@app.spooky_word_generator'] app.candy_aggregator: class: App\CandyAggregator arguments: - '@app.halloween_costume_creator' - '%kernel.project_dir%' app.doorbell_ring_event_subscriber: class: App\DoorbellRingEventSubscriber tags: ['kernel.event_subscriber']
11. services: _defaults: autowire: true autoconfigure: true public: false App\: resources: ../src services.yaml
12. services: _defaults: autowire: true autoconfigure: true public: false $container->get(‘my_service’) is dead! Extend from AbstractController now!
13. @nicolasgrekas Symfony 4 spirit Keep coding features By automating your configuration and providing you with great error messages
14. Don’t hack the conventions doing code Keep writing configuration for the exceptions to the rules @weaverryan
15. services: _defaults: autowire: true autoconfigure: true public: false bind: $projectRoot: '%kernel.project_dir%'
16. services: _defaults: autowire: true autoconfigure: true public: false bind: string $projectRoot: '%kernel.project_dir%' Stricter bindings
17. services: _defaults: autowire: true autoconfigure: true public: false bind: Symfony\Contracts\Cache\CacheInterface $apiCache: '@api.cache' Works also for services
18. services: Symfony\Contracts\Cache\CacheInterface $apiCache: '@api.cache' Named autowiring aliases
19. services: Symfony\Contracts\Cache\CacheInterface $apiCache: '@api.cache' Your favorite bundles can provide some!
20. bin/console debug:autowiring
21. bin/console debug:autowiring Lists only autowiring aliases. They are the only useful services! \o/
22. @weaverryan Environment Variables
23. @weaverryan Our app needs a production API Key
24. @weaverryan class DoorbellRingEventSubscriber { private $apiKey; public function __construct(string $apiKey) { $this->apiKey = $apiKey; } } services: _defaults: bind: $apiKey: 'ILOVECANDY' Classic problem: avoid hardcoding secret values!
25. @weaverryan services: _defaults: bind: $apiKey: '%env(API_KEY)%' // how the compiled code looks $s = new DoorbellRingEventSubscriber(getenv('API_KEY')); API_KEY=ILOVECANDY
26. Great! So environment vars are more secure than parameters.yml …right? @weaverryan
27. Not Really @weaverryan But they are more flexible
28. Let’s read from a Secrets File @weaverryan
29. services: _defaults: bind: $apiKey: '%env(key:API_KEY:json:file:SECRETS_FILE)%' (see EnvProcessor) $secretsFile = getenv('SECRETS_FILE'); $data = json_decode( file_get_contents($secretsFile) ); $s = new DoorbellRingEventSubscriber( $data['API_KEY'] );
30. How do we define environment variables? @weaverryan
31. @weaverryan Use real env vars from your OS! and .env files for defaults+local values
32. @weaverryan .env .env.local .env.test .env.test.local .env files? commit gitignore commit gitignore defaults only local values defaults local values Real env vars are never overridden
33. @weaverryan Better recipes Better defaults Better experience
34. framework: session: cookie_secure: auto cookie_samesite: lax routing: utf8
35. @weaverryan Upgrading a flex- enabled app?
37. $ git commit $ rm symfony.lock $ rm config/ -r $ rm src/ -r $ composer sync-recipes $ git diff
38. $ composer sync-recipes --force $ git diff
39. @weaverryan Upgrading a NON flex-enabled app?
40. Fully explicit style is still OK
41. composer req symfony/flex composer sync-recipes
42. Bonus - advanced - slide @weaverryan
43. services: App\MyHeavyConnection: tags: - { name: proxy, interface: App\MyConnectionInterface } Works with final classes! \o/
44. services: App\MyBlockRender: arguments: - !tagged_locator { tag: block, index_by: block_name } App\SomeBlock: tags: { name: block, block_name: some_block } New in 4.3 use !tagged to get an iterator
46. @nicolasgrekas If you think Symfony is awesome Please tell the World! Thank you!