Add meta tags on a page generated by a custom module

Question

I am trying to modify the meta tags of one of the pages of my web. For example, I want to change the title, the description and add the robots tag.

I have tried using the token and metatag modules to change this, but it is too generic and I do not see the option to change it individually on each page.

Also keep in mind that the page on which I want to change these tags is generated by a custom module: creating the Twig manually and generating the URL by routing.yml. There's the problem, that by not generating by the back, it does not recognize it as a page.

Answer 1

Inside module_name.module:

/**
 * Implements hook_page_attachments().
 */
function module_name_page_attachments(array &$page) {
  $description = [
    '#tag' => 'meta',
    '#attributes' => [
      'name' => 'description',
      'content' => 'This is content.',
    ],
  ];
  $page['#attached']['html_head'][] = [$description, 'description'];
}

Answer 2

I've tested successfuly Metatag Routes module for Drupal 8. The module adds a button in the default metatag dashboard page. The user can configure metatags for custom controllers generated by code.

To complete the solution where we use a hook. We can add a condition to apply the meta description to a specific route:

/**
 * Implements hook_page_attachments().
 */
function module_name_page_attachments(array &$page) {
  // Check if the current route matches the desired route.
  $current_route_name = \Drupal::routeMatch()->getRouteName();

  if ($current_route_name == 'name_of_the_desired_route') {
    $description = [
      '#tag' => 'meta',
      '#attributes' => [
        'name' => 'description',
        'content' => 'This is the description of the desired route.',
      ],
    ];
    $page['#attached']['html_head'][] = [$description, 'description'];
  }
}

Answer 3

Metatag_routes does not work if your path has parameters. For example, in my case:

avt_general.page_resources:
  path: '/group/{groupid}/recursos'
  defaults:
  ...

When you add new metatags for "/gruoup/something/recursos" the module associates the data with "avt_general.page_resources", so you cannot add more metatags to "/gruoup/something2/recursos". Hope this helps.