This presentation was given at a PHP Antwerp Meetup: https://www.meetup.com/phpantwerp/events/237632633/ Magento 2 is a commerce platform released since November 2015. In this introduction I’ll focus on the open source version, Magento Community and show you how easy it is to start creating modules for this platform. These modules can be used to customize your store or to publish on the Magento Marketplace.

1. Magento 2 module development
An introduction
Joke Puts - @jokeputs
PHP developer at PHPro

2. What is Magento?
Lets get that question out of the way

3. A commerce platform
Not just a framework

4. composer create-project symfony/framework-standard-edition
composer create-project magento/project-community-edition

5. It’s open source!
The community edition that is
https://github.com/magento/magento2

6. What's underneath the hood?
Well… a bit of everything

7. What’s this “module” thing?
An extension, a plugin, … a set of files that makes a feature

8. What can I do with it?
§Create a composer package
§Create customizations for your commerce platform
§Sell them on the Magento Marketplace

9. Edition 1-9 extensions
10-30
extensions
31-50
extensions
50+ extensions
Community 10% 53% 26% 11%
Enterprise 9% 32% 27% 32%

10. Setting it up
Not even a “Hello world”

11. Adding a customization to your installation?
Start in the app/code directory
Creating a reusable feature?
Create a composer package

12. §etc/module.xml
§registration.php
§composer.json
https://github.com/jokeputs/mage2-module-setup

13. registration.php
<?php
MagentoFrameworkComponentComponentRegistrar:
:register(
MagentoFrameworkComponentComponentRegistr
ar::MODULE,
'Vendor_Module',
__DIR__
);

14. etc/module.xml
<?xml version="1.0" ?>
<config>
<module
name="Vendor_Module"
setup_version="1.0.0" />
</config>

15. composer.json
{
"name": "vendor/module",
"type": "magento2-module",
"version": "1.0.0",
"require": {
"php": "~7.0.0|~7.1.0",
"magento/framework": "100.1.*"
},

16. But wait... there’s more!
Or at least there should be

17. Make this guy your friend!
https://github.com/phpro/grumphp

18. grumphp.yml
phpcs:
standard: "ruleset.xml"
show_warnings: false
ignore_patterns:
- "vendor"
- "Test/Unit"
triggered_by: [php]

19. grumphp.yml
triggered_by: [php]
phpunit:
metadata:
priority: 100

20. grumphp.yml
git_blacklist:
keywords:
- "die("
- "var_dump("
- "exit;"
- "console.log("
triggered_by: [php,js]

21. Letting Magento know what’s up
Registering your module

22. bin/magento setup:upgrade

23. Lets go a little deeper
We only dipped our toe in the water

24. Model-View-Control pattern
§ Block
§ Controller
§ Model
§ Setup
§ etc
§ frontend
§ routes.xml
§ adminhtml
§ routes.xml
§ view
§ frontend
§ adminhtml

25. … But it doesn’t do what I want
Change the “core”

26. Adapting the core
§Dependency injection
§Observers
§Plugins

27. Dependency injection
§DI via constructor
§Api: interfaces for a module
§etc/di.xml, etc/frontend/di.xml, etc/adminhtml/di.xml
§Class preferences
§Constructor arguments

28. DI: Class preferences
<preference
for="MagentoCustomerApiAddressRepositoryInter
face"
type="MagentoCustomerModelResourceModelAddre
ssRepository" />

29. DI: Constructor arguments
<type name="MagentoCustomerModelVisitor">
<arguments>
<argument name="ignoredUserAgents" xsi:type="array">
<item name="google1" xsi:type="string">Googlebot/1.0
(googlebot@googlebot.com http://googlebot.com/)</item>
<item name="google2" xsi:type="string">Mozilla/5.0
(compatible; Googlebot/2.1; +http://www.google.com/bot.html)</item>
<item name="google3" xsi:type="string">Googlebot/2.1
(+http://www.googlebot.com/bot.html)</item>
</argument>
</arguments>
</type>

30. Events
<event
name="admin_system_config_changed_section_catalo
g">
<observer
name="catalog_update_price_attribute"
instance="MagentoCatalogObserverSwitchPriceAt
tributeScopeOnConfigChange" />
</event>

31. Plugins
• Modifies behavior of a public method of a class
• Before method
• Runs before the method
• Receives the arguments of the method
• After method
• Runs after completion of the method
• Receives the output of the method
• Around method
• Runs both before and after the method
• Receives the arguments of the method
• Receives a callable, which will give the output of the method

32. di.xml
<type
name="MagentoEavModelEntityAttributeBackend
AbstractBackend">
<plugin name="attributeValidation"
type="MagentoCatalogPluginModelAttributeBac
kendAttributeValidation"/>
</type>

33. AttributeValidation.php
public function aroundValidate(AbstractBackend
$subject, Closure $proceed, DataObject $entity)
{
$isAllowedType =
!empty(array_filter(array_map(function
($allowedEntity) use ($entity) {
return $entity instanceof $allowedEntity;
}, $this->allowedEntityTypes)));
...
return $proceed($entity);
}

34. The one tip…
You know, the one to rule them all

35. Look at the core
Know it and understand it

36. Can’t get enough?
I got just the thing for you

38. Thank you!
https://joind.in/talk/8a633