DDD on example of Symfony (SymfonyCamp UA 2014)

How I realized that MVC is a myth and why MVC duped us for a years.

Transcript

1. DDD on example of Symfony Oleg ZInchenko 1cdecoder@gmail.com
2. cystbear Symfony expert MongoDB adept Erlang fun OSS doer KNPer https://twitter.com/1cdecoder https://github.com/cystbear http://knplabs.com/
3. What this talk about?
4. About useful tool/lib?
5. About success story?
6. No! It’s about idea Motivation!
7. MVC
8. Where to store business logic? Model View Controller
9. Where to store business logic? Model View Controller
10. Where to store business logic? Model View Controller
11. Where to store business logic? Model View Controller -- YEAH!
12. Welcome to Fat Stupid Ugly Controllers FSUC/FUC http://blog.astrumfutura.com/2008/12/the-m-in-mvc-why-models-are-misunderstood-and-unappreciated/ http://zendframework.ru/anonses/model-with-mvc http://habrahabr.ru/post/175465/
13. Anemic (Domain) Model http://www.martinfowler.com/bliki/AnemicDomainModel.html http://habrahabr.ru/post/224879/ “In essence the problem with anemic domain models is that they incur all of the costs of a domain model, without yielding any of the benefits.” Martin Fowler
14. Persistence Layer Model
16. What is Not MVC (phew!) Request / Response Framework HTTP Framework http://fabien.potencier.org/article/49/what-is-symfony2
17. What about model, persistence layer?
18. Meet Doctrine http://www.doctrine-project.org/ SQL -- DBAL + ORM MongoDB CouchDB OrientDB PHPCR ODM OXM
19. http://www.martinfowler.com/articles/injection.html http://fabien.potencier.org/article/11/what-is-dependency-injection http://fabien.potencier.org/article/13/introduction-to-the-symfony-service-container
20. Services http://groovy.codehaus.org/ https://grails.org/ Single Class With its Deps (min) set Easy to Replace Easy to Test MVC(S)!
21. Controller’s pray https://twitter.com/ornicar Get Request Submit form if any Call one Service method Return Response Rendering HTML far away
22. Managers Managers Managers http://blog.codinghorror.com/i-shall-call-it-somethingmanager/ http://stackoverflow.com/questions/1866794/naming-classes-how-to- avoid-calling-everything-a-whatevermanager <SmtManager> <WhatEverManager> <MyManager> <EtcManager>
23. Real Pain class BackendUserProgramsPossessionFormHandler { protected $dep1; // deps holder props public function __construct(DepsClass $dep1 /*, ...*/) { $this->dep1 = $dep1; } public function process(Form $form) { $this->dep1->makeHappy($form); // ... }
24. How Kris writes Symfony apps#44 https://twitter.com/kriswallsmith http://www.slideshare.net/kriswallsmith/how-kris-writessymfonyapps
25. https://twitter.com/kriswallsmith http://www.slideshare.net/kriswallsmith/how-kris-writessymfonyapps How Kris writes Symfony apps#44
26. https://twitter.com/mr_r_miller/status/522343384900718592 Just A Thought
27. Domain Logic Patterns http://martinfowler.com/books/eaa.html
28. Domain Logic Patterns http://martinfowler.com/books/eaa.html Transaction Script Domain Model Table Module Service Layer
29. Transaction Script
30. Domain Model
31. Table Module
32. Domain Logic & Application logic
33. Service Layer
35. What is next? RAD DDD Patterns Examples Layers Goodies
36. DDD != RAD Code First Do not Care about persistence (yet)
37. Domain Model Repository Value Object DTO Strategy State Patterns & Code
38. Domain Model
39. Domain Model <?php namespace MegaCorp\Core\Product; class Product { private $id; private $name; private $recognitionStrategy; public function __construct( ProductId $id, $name, $recognitionStrategy ) { $this->id = $id; $this->name = $name; $this->recognitionStrategy = $recognitionStrategy; }
40. Repository <?php namespace MegaCorp\Core\Product; interface ProductRepository { public function find(ProductId $productId); public function findAll(); public function add(Product $product); public function remove(Product $product); }
41. Value Object <?php namespace MegaCorp\Core; class ProductId { private $value; public function __construct($value) { $this->value = (string) $value; } public function getValue() { return $this->value; } }
42. Value Object DateRange
43. Value Object DateRange <?php public function findByDateRange( \DateTime $from, \DateTime $to ) class DateRange { private $from; private $to; public function __construct(\DateTime $from, \DateTime $to) { $this->from = $from; $this->to = $to; } } public function findByDateRange(\DateRange $range)
44. Value Object Money
45. <?php class Money { private $amount; private $currency; public function __construct( $amount, Currency $currency ) { // ... } } Value Object Money
46. <?php class ProfileData { public $firstName; public $lastName; public $birthday; } DTO
47. Strategy
48. ______ ______ _______ _______ / | / __ \ | \ | ____| | ,----'| | | | | .--. || |__ | | | | | | | | | || __| | `----.| `--' | | '--' || |____ \______| \______/ |_______/ |_______|
49. src └── MegaCorp ├── ApiBundle │ ├── Controller │ │ └── ... │ └── MegaCorpApiBundle.php ├── Core │ └── Product │ ├── Product.php │ ├── ProductId.php │ └── ProductRepository.php └── CoreBundle ├── Controller │ └── ... ├── Repository │ ├── InMemoryProductRepository.php │ └── MongoDbProductRepository.php └── MegaCorpCoreBundle.php Directory structure
50. Layers
51. Layers Domain Layer -- heart of your application, Entities and Repositories Application Layer -- Controllers Presentation Layer -- Templates / DTOs for serializer Infrastructure Layer -- framework, persistence, concrete implementations of Domain Layer
52. Useful goodies
53. BBB DDD by Eric Evans http://amzn.com/0321125215/
54. DDD Quickly by InfoQ http://www.infoq.com/minibooks/domain-driven-design-quickly
55. PoEAA by Martin Fowler http://amzn.com/B008OHVDFM/
56. DDD and Patterns by Jimmy Nilsson http://amzn.com/B0054KOKQQ/
57. Links http://dddcommunity.org/ http://williamdurand.fr/ http://welcometothebundle.com/ http://verraes.net/ http://jimmynilsson.com/blog/ http://www.martinfowler.com/ http://elephantintheroom.io/ -- podcast http://msdn.microsoft.com/en-us/magazine/dd419654.aspx http://www.martinfowler.com/bliki/AnemicDomainModel.html http://martinfowler.com/bliki/CQRS.html
59. Thanks!