Issue #3218356: Process plugin: service

src/Plugin/migrate/process/Service.php

+<?php
+
+namespace Drupal\migrate_plus\Plugin\migrate\process;
+
+use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Drupal\migrate\Plugin\migrate\process\Callback;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Provides a plugin to use a callable from a service class.
+ *
+ * Example:
+ *
+ * @code
+ * process:
+ *   filemime:
+ *     plugin: service
+ *     service: file.mime_type.guesser
+ *     method: guessMimeType
+ *     source: filename
+ * @endcode
+ *
+ * All options for the callback plugin can be used, except for 'callable',
+ * which will be ignored.
+ *
+ * @see \Drupal\migrate\Plugin\migrate\process\Callback
+ *
+ * @MigrateProcessPlugin(
+ *   id = "service"
+ * )
+ */
+class Service extends Callback implements ContainerFactoryPluginInterface {
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    if (!isset($configuration['service'])) {
+      throw new \InvalidArgumentException('The "service" must be set.');
+    }
+    if (!isset($configuration['method'])) {
+      throw new \InvalidArgumentException('The "method" must be set.');
+    }
+    if (!$container->has($configuration['service'])) {
+      throw new \InvalidArgumentException(sprintf('You have requested the non-existent service "%s".', $configuration['service']));
+    }
+    $service = $container->get($configuration['service']);
+    if (!method_exists($service, $configuration['method'])) {
+      throw new \InvalidArgumentException(sprintf('The "%s" service has no method "%s".', $configuration['service'], $configuration['method']));
+    }
+
+    $configuration['callable'] = [$service, $configuration['method']];
+    return new static($configuration, $plugin_id, $plugin_definition);
+  }
+
+}