Drupal dev days 2014 presentation in Szeged. Plugin system in drupal 8. This is the unchanged version of my slides.

1. Drupal 8 plugin system
aspilicious!

2. About me
• Bram Goffings
@aspilicious
• Drupal developer
• Work for Nascom
www.nascom.be
• Maintainer of Display Suite
• Drupal 8 core contributor

3. Target audience
• Site builders & module developers
• Experience with module development
• Understanding of the hook system
• Know how to handle object oriented code

4. Success?
• Nobody is scared anymore
• Everyone can make a *basic* plugin type

5. Not the expert
• I’m an end user, just like you
• Learned by trying (and failing)
• I can say stupid things

6. Drupal developer
• Mr. Steven
• Brave drupal 7 expert
• Made his first Drupal 8 site
• Wants to build a plugin
system

7. Client
• Mr. Arnold
• Rich webmaster
• Loves cars

8. • I want to choose my favorite car on my profile from
a predefined list.
• It should be possible to plug in different cars into
the list.
• The name and an image of the selected car should
placed on the homepage.

9. I take the job…

10. Step 1
I want to choose my favorite car on my profile
from a predefined list.

11. Arnold’s wireframe

12. Steven’s plan
• Add a “Car selector” field
• Create a custom select widget

13. The drupal 7 way
• Implements hook_field_widget_info()
• Implements hook_field_widget_form()

14. Those hooks are gone!

15. They are plugin-y-fied!

16. What is a plugin?
Plugins are small pieces of functionality that are
swappable.
Plugins that perform similar functionality are of the
same plugin type.

17. Field widget plugins!
• There is a “widget” plugin type!
• Each field widget is from that type!

18. Structure

19. SelectWidget.php
namespace DrupaloptionsPluginFieldFieldWidget;

20. SelectWidget.php
namespace DrupaloptionsPluginFieldFieldWidget;

21. SelectWidget.php
namespace DrupaloptionsPluginFieldFieldWidget;

22. SelectWidget.php
namespace DrupaloptionsPluginFieldFieldWidget;

23. Namespaces
• Namespaces were introduced in PHP 5.3
• Used to avoid name collisions

24. PSR-0
• Aims to provide a standard file, class and namespace
convention to allow plug-and-play code.
• Uses the defined namespaces to automatically load files when
needed.
• One on one mapping between namespaces and directory
structure.

25. SelectWidget.php
namespace DrupaloptionsPluginFieldFieldWidget;

26. Structure

27. PSR-4
• “New standard”
• Makes alternative mapping possible
• Drupal will use it to remove “unneeded” folders. The empty
*drupal* and *module-name* folder won’t be needed
anymore.

28. Let’s recap
• We know how to find plugins
• We understand namespaces and the directory
structure
• We understand PSR-0 and the difference between
PSR-4

29. SelectWidget.php

30. Available methods

31. Car module structure

32. car.info.yml

34. Step 1: done

36. Let’s recap
• We know how to start with writing a field widget
plugin
• We know how to start writing a custom module

37. Step 2
It should be possible to plug in
different cars into the list.

38. Steven’s plan
• Create a custom plugin type named “Car”
• Create two sample car plugins

39. Custom plugin type
• Create a plugin manager service record
• Create an annotation class
• Create the plugin manager class

40. Custom plugin type

41. car.services.yml

44. Car module structure
(part 2)

45. Sample plugins

46. Sample plugins

47. getOptions() v2

48. Debug output

49. Car module structure
(part 3)

50. Let’s recap
• We know how to write a basic plugin manager
• We know how to handle annotations
• We know how to get all the plugin definitions

51. Disadvantage
Each car requires a plugin

52. Derivative
• Allows you to create multiple plugin definitions
through a single plugin class.

53. Derivative example!
• Create a yml file containing cars!
• Create a derivative plugin!
• Create a definition for each car in the yml file!

54. cars-example.yml

55. YamlCar.php

57. Step 2: done

59. Let’s recap
• We know when to use derivatives
• We are able to build one

60. Step 3
The name and an image of the selected car should
placed on the homepage.

61. Steven’s plan
• Add a function to the plugins that returns an image
url
• Create the frontpage

67. hook_menu is gone!

68. car.routing.yml

72. Car module structure
(part 4)

73. Let’s recap
• We figured out how to add a function to a plugin
• We know how to create a plugin instance
• We saw how we should create our routes
• We learned how to build a page controller

74. The end

75. Questions?

76. THANK YOU!