How to Alter a Path in Drupal Before Saving Content

When you need a custom logic for URL generation

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When using the module pathauto, it’s best to configure the patterns in this URL: admin/config/search/path/patterns and then export them to config. But it might not be enough if you need to implement a custom logic for the URL generation.

For that, you can use hook_pathauto_alias_alter, which alters pathauto-generated aliases before saving the content.

Here’s an example of something I had to do recently:

/**
 * Implements hook_pathauto_alias_alter().
 */
function custom_module_pathauto_alias_alter(string &$alias, array &$context) {
  // Ensure this is triggered for node content.
  if ($context['module'] == 'node' && isset($context['data']['node'])) {
    $node = $context['data']['node'];

    // Check if the node has 'islands' field and it's not empty.
    if ($node->hasField('islands') && !$node->get('islands')->isEmpty()) {
      // Get the taxonomy term ID.
      $term_id = $node->get('islands')->target_id;

      // Load the taxonomy term entity to get its name.
      $term = \Drupal\taxonomy\Entity\Term::load($term_id);
      if ($term) {
        // Get the taxonomy term name and replace spaces with hyphens.
        $island_name = strtolower(str_replace(' ', '-', $term->getName()));

        //…