Article Ressources - Set up workflows with State Machine on Drupal Commerce 2.x

README.md

Article Ressources - Set up workflows with State Machine on Drupal Commerce 2.x

This is the Gist repository for my article Set up workflows with State Machine on Drupal Commerce 2.x.

Be aware that this article has been wrote for the Blog of Antistatique — Web Agency in Lausanne, Switzerland. A place where I work as Full Stack Web Developer.

Feel free to read it the full article on Medium or check it out on Antistatique.

Content of this Gist :

• WorkflowHelper.php : Contains helper methods to retrieve workflow related data from entities.
• WorkflowTransitionEventSubscriber.php : Event subscriber to handle actions on workflow-enabled entities.
• my_workflow.services.yml
• my_workflow.workflow_groups.yml
• my_workflow.workflows.yml : Workflow(s) définiation used by State Machine module.

my_workflow.services.yml

services:
  my_workflow.workflow.helper:
    class: Drupal\my_workflow\WorkflowHelper

  my_workflow.workflow_transition:
    class: Drupal\my_workflow\EventSubscriber\WorkflowTransitionEventSubscriber
    arguments: ['@my_workflow.workflow.helper']
    tags:
      - { name: event_subscriber }

my_workflow.workflow_groups.yml

product_publication:
  label: Publication
  entity_type: commerce_product

my_workflow.workflows.yml

product_publication_default:
  id: product_publication_default
  label: Commerce product publication
  group: product_publication
  states:
    draft:
      label: Draft
      published: false
    imported:
      label: Imported
      published: false
    needs_update:
      label: Needs update
      published: false
    validated:
      label: Published
      published: true
    archived:
      label: Archived
      published: false
  transitions:
    save_as_draft:
      label: Save as draft
      from: [draft, imported]
      to: draft
    validate:
      label: Publish
      from: [needs_update]
      to: validated
    needs_update:
      label: Request changes
      from: [draft, imported, validated]
      to: needs_update
    unarchive:
      label: Unarchive
      from: [archived]
      to: draft
    archive:
      label: Archive
      from: [draft, imported, needs_update, validated]
      to: archived

skeleton.md

├── my_workflow.info.yml   
├── my_workflow.services.yml   
├── my_workflow.workflow_groups.yml   
├── my_workflow.workflows.yml   
├── src   
│   ├── EventSubscriber   
│   │   └── WorkflowTransitionEventSubscriber.php   
│   ├── WorkflowHelper.php

state_machine.events.pattern_by_transition.md

[group_id].[transition_id].[pre_transition|post_transition]

state_machine.events.pattern_global.md

state_machine.[pre_transition|post_transition]

WorkflowHelper.php

<?php

namespace Drupal\my_workflow;

use Drupal\Component\Plugin\PluginInspectionInterface;
use Drupal\state_machine\Plugin\Workflow\WorkflowInterface;

/**
 * Contains helper methods to retrieve workflow related data from entities.
 */
class WorkflowHelper {

  /**
   * Checks if a state is set as published in a certain workflow.
   *
   * @param string $state_id
   *   The ID of the state to check.
   * @param \Drupal\state_machine\Plugin\Workflow\WorkflowInterface $workflow
   *   The workflow the state belongs to.
   *
   * @return bool|null
   *   TRUE|FALSE if the state is set in the workflow, NULL otherwise.
   *
   * @throwns \InvalidArgumentException
   *   Thrown when the workflow is not plugin based, because this is required to
   *   retrieve the publication state from the workflow states.
   */
  public function isWorkflowStatePublished($state_id, WorkflowInterface $workflow) {
    // We rely on being able to inspect the plugin definition. Throw an error if
    // this is not the case.
    if (!$workflow instanceof PluginInspectionInterface) {
      $label = $workflow->getLabel();
      throw new \InvalidArgumentException("The '$label' workflow is not plugin based.");
    }

    // Retrieve the raw plugin definition, as all additional plugin settings
    // are stored there.
    $raw_workflow_definition = $workflow->getPluginDefinition();
    return $raw_workflow_definition['states'][$state_id]['published'] ?? NULL;
  }

}

WorkflowTransitionEventSubscriber.php

<?php

namespace Drupal\my_workflow\EventSubscriber;

use Drupal\Core\Entity\EntityPublishedInterface;
use Drupal\my_workflow\WorkflowHelper;
use Drupal\state_machine\Event\WorkflowTransitionEvent;
use Drupal\state_machine\Plugin\Workflow\WorkflowInterface;
use Drupal\state_machine\Plugin\Workflow\WorkflowState;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;
use Drupal\commerce_product\Entity\ProductInterface;

/**
 * Event subscriber to handle actions on workflow-enabled entities.
 */
class WorkflowTransitionEventSubscriber implements EventSubscriberInterface {

  /**
   * The workflow helper.
   *
   * @var \Drupal\my_workflow\WorkflowHelper
   */
  protected $workflowHelper;

  /**
   * Constructs a new WorkflowTransitionEventSubscriber object.
   *
   * @param \Drupal\my_workflow\WorkflowHelper $workflowHelper
   *   The workflow helper.
   */
  public function __construct(WorkflowHelper $workflowHelper) {
    $this->workflowHelper = $workflowHelper;
  }

  /**
   * {@inheritdoc}
   */
  public static function getSubscribedEvents() {
    return [
      'state_machine.pre_transition' => [
        'handleAction', -180,
      ],
    ];
  }

  /**
   * Handle action based on the workflow.
   *
   * @param \Drupal\state_machine\Event\WorkflowTransitionEvent $event
   *   The state change event.
   */
  public function handleAction(WorkflowTransitionEvent $event) {
    $entity = $event->getEntity();

    // Don't handle action on non-commerce_product or non-publishable entity.
    if (!$entity instanceof ProductInterface || !$entity instanceof EntityPublishedInterface) {
      return;
    }

    // Verify if the new state is marked as published state.
    $is_published_state = $this->isPublishedState($event->getToState(), $event->getWorkflow());

    if ($is_published_state === TRUE) {
      $entity->setPublished();
    }
    elseif ($is_published_state === FALSE) {
      $entity->setUnpublished();
    }
  }

  /**
   * Checks if a state is set as published in a certain workflow.
   *
   * @param \Drupal\state_machine\Plugin\Workflow\WorkflowState $state
   *   The state to check.
   * @param \Drupal\state_machine\Plugin\Workflow\WorkflowInterface $workflow
   *   The workflow the state belongs to.
   *
   * @return bool
   *   TRUE if the state is set as published in the workflow, FALSE otherwise.
   */
  protected function isPublishedState(WorkflowState $state, WorkflowInterface $workflow) {
    return $this->workflowHelper->isWorkflowStatePublished($state->getId(), $workflow);
  }

}