The Google Tag Manager: Events module provides API to push events to GTM Datalayer from PHP.

• For a full description of the module, visit the project page: https://www.drupal.org/project/google_tag_events

• To submit bug reports and feature suggestions, or to track changes: https://www.drupal.org/project/issues/google_tag_events

This module requires GoogleTagManager module.

Install as you would normally install a contributed Drupal module. Visit: https://www.drupal.org/docs/extending-drupal/installing-modules for further information.

To push the events via Google Tag Manager: Events module you must configure at least one GTM container.

You can see gtm_events_test module for usage examples.

You can push an event directly from PHP code. It means that event will be pushed after page loading in browser.

To push event you can use 'google_tag_events' service.

google_tag_events_service()->setEvent(
  'some_event_name',
  [
    'event' => 'some_event_name'
    'foo' => 'bar'
  ]
);

After this code executing will be pushed event like

dataLayer.push({
  'event': 'some_event_name',
  'foo': 'bar'
});

You can test GTM events pushing without any configured GTM containers. Just enable debug mode on config page /admin/config/system/google-tag/events/settings.

You can use recommended browser extensions to check datalayer:

• Datalayer Checker by https://sublimetrix.com
• dataslayer by https://dataslayer.org

You can incapsulate the event data preparation code to event plugin. Plugin must be placed into tests/modules/gtm_events_test/src/Plugin/google_tag_event directory.

For example:

/**
 * Node node page visit GTM event plugin.
 *
 * @Plugin(
 *   id = "example_event_node_view",
 *   label = @Translation("Node page visit event")
 * )
 */
class ExampleEventNodeView extends GoogleTagEventsPluginBase {

  /**
   * {@inheritdoc}
   */
  public function process(array $data = NULL) {
    $data = $data ?? $this->data;

    $event_data = [
      'event' => 'node_view',
      'title' => $data['node']->getTitle(),
    ];

    return $event_data;
  }

}

Then call the service

/**
 * Implements hook_entity_view().
 */
function comment_entity_view(
    array &$build,
    EntityInterface $entity,
    EntityViewDisplayInterface $display,
    $view_mode
  ) {
  if ($entity instanceof NodeInterface) {
    google_tag_events_service()->setEvent(
      'example_event_node_view',
      ['node' => $entity]
    );
  }
}

The result of this code will be

dataLayer.push({
  'event': 'node_view',
  'title': 'Some node title'
});

A plugin name must match with event name to call plugin's process method.

• Vyacheslav Malchik (validoll) - https://www.drupal.org/u/validoll