Links and Resources for Drupal 8

• hook_menu() replacement: https://www.drupal.org/docs/8/converting-drupal-7-modules-to-drupal-8/d7-to-d8-upgrade-tutorial-convert-hook_menu-and-hook

• Routing .yml structure: https://www.drupal.org/node/2092643#section-requirements

• Managing config: Make changes, config:export, PULL from upstream, resolve conflicts (they are usually easy), config:import, PUSH and open PR.

• Running PHPUnit tests: https://www.drupal.org/docs/8/phpunit/running-phpunit-tests

• Writing/Running Custom module tests from the core testing module UI: https://www.drupal.org/docs/8/creating-custom-modules/testing-a-drupal-8-module

• Using the services container and dependency injection: https://www.drupal.org/docs/8/api/services-and-dependency-injection/services-and-dependency-injection-in-drupal-8

• Add a class to a field's markup based on a value: https://www.drupal.org/forum/support/module-development-and-code-questions/2017-03-31/add-class-to-field-in-drupal-8

• Views Template names (Twig debug does not output this info): https://api.drupal.org/api/drupal/core%21modules%21views%21views.theme.inc/group/views_templates/8.2.x

  • Should be able to use Twig Tweak (contrib module) to view variables/objects/arrays/etc. and understand values available within a given template (and what to add):

  {{ drupal_dump(variable_name) }} 
  

  • ...to print out the results of any variable/object/array within a Twig template.

• cc is very useful DX tool. Clearing the render cache is currently a very frequent event. https://www.drupal.org/docs/user_guide/en/prevent-cache-clear.html

• Drupal 8 equivalent of cc all is cr all. cr stands for Cache Rebuild.

• srcset and responsive images: https://chromatichq.com/blog/responsive-images-drupal-8-using-srcset

• When you have a renderable array ($variables in a preprocess context is a render array now) you can set $renderable['#cache']['max-age'] = 0 to avoid having to flush the render cache after every code change.

• Rendering an exposed form (Views) programmatically: https://www.drupal.org/forum/support/module-development-and-code-questions/2017-02-20/how-to-programmatically-render-a-view

  • Twig Tweak also includes simpler (perhaps less robust) support for embedding views/blocks within Twig.

  {{ drupal_view('view_machine_name', 'display_machine_name', arg1, arg2, ...) }}
  
  {{ drupal_view('block_name') }}
  

  Arguments are passed as contextual filter values in the order they are supplied see docs.

  Of note: We have had some difficulty using entity references via contextual links (one content type referencing another content type in its display, etc.)

• Don't manage modules with drush anymore. Download them with composer install drupal/MY_PROJECT_NAME. If you need to install the module from the CLI after -- use vendor/bin/drupal moi MY_PROJECT_NAME.

• modules no longer can be disabled. only enabled and uninstalled. Uninstalling modules will remove all associated content/fields/etc.

  • Adding a hook_uninstall within .install is a good/valid way to clear out dead config settings after uninstalling a module (if custom):
  • Custom modules and contrib modules can be shipped with config that is installed when the module is first enabled (and not again unless fully uninstalled.)

• Some useful ReactJS resources to get up to speed on some core concepts:

  • Hooks

  • Functional Components

• Serializing Nodes with the Serializer services and Type Data API:

$serializer = \Drupal::service('serializer');
// Useful for `drupalSettings` or PHP
$arrayOfData = $serializer->normalize($entity, 'json', ['plugin_id' => 'entity']);
// Useful for API responses or other output scenarios
$jsonString = $serializer->serialize($entity, 'json', ['plugin_id' => 'entity'])

• Implement new Serializers for entity types: https://www.drupal.org/docs/8/api/serialization-api/changing-the-way-serializer-handles-entities

• JSON:API vs RESTful Web Services: https://www.drupal.org/docs/8/modules/jsonapi/jsonapi-vs-cores-rest-module

• Programmatically create blocks: https://hechoendrupal.gitbooks.io/drupal-console/en/commands/generate-plugin-block.html