Challenges building complex applications with Symfony2

Symfony2 ecosystem provides us with convenient ways of getting the job done. Over time conveniences like base controller, service locator, doctrine base repository and others promotes tight coupling becoming and obstacle in the development. We will focus on practical examples on how to make our code more domain focused and less dependent on Symfony2 ecosystem.

Transcript

1. Challenges building complex applications with Symfony2 Eduardo Oliveira entering @ Github Sorry no twitter
2. Why I can talk about PHP and Symfony2? Note: The high number of deletes is due to delete PHPdoc generated docs. A MQ, no Symfony2 on this just PHP and Redis. … …
3. Talk target • Rich domain • Complex applications • Programmers that care about code
4. Doesn’t fit ! • CRUD applications • Simple applications, go with RAD approach instead • You are on it just for the money • Prototype (make sure you don’t ship it)
5. About Symfony2
6. One of the most popular frameworks in the PHP community
7. Built on top of best design patterns
8. A set of decoupled and standalone components
9. Is Symfony2 the silver bullet?
10. Symfony2 is a good tool
11. Programmers that care build good systems not tools
12. A new Symfony2 project Starts with the dream to write: ! • elegant code • code that you are proud • reusable code
13. After some months… Big Ball of Mud
14. Lets start…
17. Entity
18. Typical entity Source: The Book for Symfony 2.4
19. Typical entity • Thin • No behavior • Just a bag of getters and setters
20. Controller
21. Typical controller Source: The Book for Symfony 2.4
22. Typical controller • Fat • Hidden dependencies • Unit testing is a far away dream
23. Form
24. Typical form Source: The Book for Symfony 2.4
25. Form binds to model entity Source: The Book for Symfony 2.4
26. Typical validation Source: The Book for Symfony 2.4
27. Typical form/entity • High coupling (UI and domain) • Mixed concerns (same validation UI and domain) • Domain entities can be constructed in an invalid state
28. Repository
29. Typical repository interface Source: The Book for Symfony 2.4
30. Typical repository Source: The Book for Symfony 2.4
31. Typical use of repository Source: The Book for Symfony 2.4
32. Typical repository • Magic • Domain coupled to infrastructure, not to a contract • No idea what queries your application run
33. Is there any hope? ! Just if you deeply care about your code
34. Entities & Doctrine ORM
35. Entities & Doctrine ORM • Data mapper (entity unaware of persistence) • No need for setters/getters, Doctrine uses Reflection • You own the object constructor
36. Entities & Doctrine ORM Paradise? Almost, but … No VO’s support :(
37. Entities & Doctrine ORM Sources: https://twitter.com/beberlei/status/298569925830799360 http://www.whitewashing.de/2013/02/04/doctrine_and_solid.html
38. Entities & Doctrine ORM
39. Entities & Doctrine ORM
40. Entities & Doctrine ORM
41. Entities & Doctrine ORM
42. Entities & Doctrine ORM recipe Try VO’s support, if doesn’t fit in your use case don’t use Doctrine ORM 
 it will hurt too much your code. ! You can still and should use Doctrine DBAL.
43. Controllers recipe • Controllers as services • Don’t use service locator • Don’t extend the Symfony2 base controller • Group your dependencies and inject them
44. Forms
45. Forms • The Symfony2 component more loved/ hated • Integrates well with validation • You can control construction with empty_data • It requires getters
46. Forms Source: http://williamdurand.fr/2013/12/16/enforcing-data-encapsulation-with-symfony-forms/
47. Forms Source: https://twitter.com/couac/status/412677521977921536
48. Forms Source: https://twitter.com/couac/status/412677521977921536
49. Forms Source: https://twitter.com/couac/status/412677521977921536
50. Forms recipe ! • Don’t bind forms to domain entities • Add specific entities to support the presentation layer • Use Symfony validations on presentation • Use Forms as services
51. Repositories
52. Repositories Source: http://williamdurand.fr/2013/08/07/ddd-with-symfony2-folder-structure-and-code-first/
53. Repositories recipe ! Don’t use the base Doctrine repository ! Want to know more? https://github.com/entering/doctrine- repository
54. Review https://joind.in/talk/view/11345