--- /dev/null
+<?php
+
+/**
+ * @file
+ * Hooks provided by the User module.
+ */
+
+/**
+ * @addtogroup hooks
+ * @{
+ */
+
+/**
+ * Act on user account cancellations.
+ *
+ * This hook is invoked from user_cancel() before a user account is canceled.
+ * Depending on the account cancellation method, the module should either do
+ * nothing, unpublish content, or anonymize content. See user_cancel_methods()
+ * for the list of default account cancellation methods provided by User module.
+ * Modules may add further methods via hook_user_cancel_methods_alter().
+ *
+ * This hook is NOT invoked for the 'user_cancel_delete' account cancellation
+ * method. To react to that method, implement hook_ENTITY_TYPE_predelete() or
+ * hook_ENTITY_TYPE_delete() for user entities instead.
+ *
+ * Expensive operations should be added to the global account cancellation batch
+ * by using batch_set().
+ *
+ * @param array $edit
+ * The array of form values submitted by the user.
+ * @param \Drupal\Core\Session\AccountInterface $account
+ * The user object on which the operation is being performed.
+ * @param string $method
+ * The account cancellation method.
+ *
+ * @see user_cancel_methods()
+ * @see hook_user_cancel_methods_alter()
+ */
+function hook_user_cancel($edit, $account, $method) {
+ switch ($method) {
+ case 'user_cancel_block_unpublish':
+ // Unpublish nodes (current revisions).
+ module_load_include('inc', 'node', 'node.admin');
+ $nodes = \Drupal::entityQuery('node')
+ ->condition('uid', $account->id())
+ ->execute();
+ node_mass_update($nodes, ['status' => 0], NULL, TRUE);
+ break;
+
+ case 'user_cancel_reassign':
+ // Anonymize nodes (current revisions).
+ module_load_include('inc', 'node', 'node.admin');
+ $nodes = \Drupal::entityQuery('node')
+ ->condition('uid', $account->id())
+ ->execute();
+ node_mass_update($nodes, ['uid' => 0], NULL, TRUE);
+ // Anonymize old revisions.
+ db_update('node_field_revision')
+ ->fields(['uid' => 0])
+ ->condition('uid', $account->id())
+ ->execute();
+ break;
+ }
+}
+
+/**
+ * Modify account cancellation methods.
+ *
+ * By implementing this hook, modules are able to add, customize, or remove
+ * account cancellation methods. All defined methods are turned into radio
+ * button form elements by user_cancel_methods() after this hook is invoked.
+ * The following properties can be defined for each method:
+ * - title: The radio button's title.
+ * - description: (optional) A description to display on the confirmation form
+ * if the user is not allowed to select the account cancellation method. The
+ * description is NOT used for the radio button, but instead should provide
+ * additional explanation to the user seeking to cancel their account.
+ * - access: (optional) A boolean value indicating whether the user can access
+ * a method. If 'access' is defined, the method cannot be configured as
+ * default method.
+ *
+ * @param array $methods
+ * An array containing user account cancellation methods, keyed by method id.
+ *
+ * @see user_cancel_methods()
+ * @see \Drupal\user\Form\UserCancelForm
+ */
+function hook_user_cancel_methods_alter(&$methods) {
+ $account = \Drupal::currentUser();
+ // Limit access to disable account and unpublish content method.
+ $methods['user_cancel_block_unpublish']['access'] = $account->hasPermission('administer site configuration');
+
+ // Remove the content re-assigning method.
+ unset($methods['user_cancel_reassign']);
+
+ // Add a custom zero-out method.
+ $methods['mymodule_zero_out'] = [
+ 'title' => t('Delete the account and remove all content.'),
+ 'description' => t('All your content will be replaced by empty strings.'),
+ // access should be used for administrative methods only.
+ 'access' => $account->hasPermission('access zero-out account cancellation method'),
+ ];
+}
+
+/**
+ * Alter the username that is displayed for a user.
+ *
+ * Called by $account->getDisplayName() to allow modules to alter the username
+ * that is displayed. Can be used to ensure user privacy in situations where
+ * $account->getDisplayName() is too revealing.
+ *
+ * @param string|Drupal\Component\Render\MarkupInterface $name
+ * The username that is displayed for a user. If a hook implementation changes
+ * this to an object implementing MarkupInterface it is the responsibility of
+ * the implementation to ensure the user's name is escaped properly. String
+ * values will be autoescaped.
+ * @param \Drupal\Core\Session\AccountInterface $account
+ * The user object on which the operation is being performed.
+ *
+ * @see \Drupal\Core\Session\AccountInterface::getDisplayName()
+ * @see sanitization
+ */
+function hook_user_format_name_alter(&$name, $account) {
+ // Display the user's uid instead of name.
+ if ($account->id()) {
+ $name = t('User @uid', ['@uid' => $account->id()]);
+ }
+}
+
+/**
+ * The user just logged in.
+ *
+ * @param object $account
+ * The user object on which the operation was just performed.
+ */
+function hook_user_login($account) {
+ $config = \Drupal::config('system.date');
+ // If the user has a NULL time zone, notify them to set a time zone.
+ if (!$account->getTimezone() && $config->get('timezone.user.configurable') && $config->get('timezone.user.warn')) {
+ drupal_set_message(t('Configure your <a href=":user-edit">account time zone setting</a>.', [':user-edit' => $account->url('edit-form', ['query' => \Drupal::destination()->getAsArray(), 'fragment' => 'edit-timezone'])]));
+ }
+}
+
+/**
+ * The user just logged out.
+ *
+ * @param $account
+ * The user object on which the operation was just performed.
+ */
+function hook_user_logout($account) {
+ db_insert('logouts')
+ ->fields([
+ 'uid' => $account->id(),
+ 'time' => time(),
+ ])
+ ->execute();
+}
+
+/**
+ * @} End of "addtogroup hooks".
+ */