trigger_example.module in Examples for Developers 6

File

trigger_example/trigger_example.module

<?php

/**
 * @defgroup trigger_example Example: Trigger
 * @ingroup examples
 * @{
 * Examples of module-defined triggers. (drupal 6)
 *
 * This example is part of the Examples for Developers Project which you can download
 * and experiment with here: http://drupal.org/project/examples
 */

/**
 * Implementation of hook_help().
 */
function trigger_example_help($path, $arg) {
  switch ($path) {
    case 'trigger_example':
      return '<p>' . t('Use this page to call hook_trigger_example() with the ping and pong operations. You can create actions to display a message or email the user on the <a href="@actions-url">Actions settings page</a> and assign these actions with the ping and pong events on the <a href="@triggers-url">Triggers settings page</a>.', array(
        '@actions-url' => url('admin/settings/actions'),
        '@triggers-url' => url('admin/build/trigger/trigger_example'),
      )) . '</p>';
    case 'admin/build/trigger/trigger_example':
      $explanation = '<p>' . t('Triggers are system events, such as when new content is added or when a user logs in. Trigger module combines these triggers with actions (functional tasks), such as unpublishing content or e-mailing an administrator. The <a href="@url">Actions settings page</a> contains a list of existing actions and provides the ability to create and configure additional actions.', array(
        '@url' => url('admin/settings/actions'),
      )) . '</p>';
      return $explanation . '<p>' . t('Below you can assign actions to run when certain comment-related triggers happen. For example, you could promote a post to the front page when a comment is added.') . '</p>';
  }
}

/**
 * Implementation of hook_menu().
 *
 * Provide a form that can be used to fire the module's triggers.
 */
function trigger_example_menu() {
  $items['trigger_example'] = array(
    'title' => t('Trigger Example'),
    'description' => t('Provides a form to test the triggers.'),
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      'trigger_example_form',
    ),
    'access callback' => TRUE,
  );
  return $items;
}

/**
 * Implementation of hook_hook_info().
 *
 * This hook is used to tell Drupal which hooks we provide that can be used
 * as triggers for actions. We provide a text description of when each of the
 * operations occurs.
 */
function trigger_example_hook_info() {
  return array(
    'trigger_example' => array(
      // One important thing to note here. If you want to use the trigger
      // module's default menu and forms handlers your hook needs to have the
      // same name as your module. If you've got the "foo" module with a hook
      // "hook_fooapi" then you're going to have to implement hook_forms and
      // map the form ids back to the trigger_assign_form callback.
      'trigger_example' => array(
        'ping' => array(
          'runs when' => t('A ping happens'),
        ),
        'pong' => array(
          'runs when' => t('A pong happens'),
        ),
      ),
    ),
  );
}

/**
 * Function to generate ping events and invoke hook_trigger_example().
 */
function trigger_example_ping() {
  $count = variable_get('trigger_example_pings', 0) + 1;

  // Invoke hook_trigger_example() with the ping operation.
  module_invoke_all('trigger_example', 'ping', $count);
  variable_set('trigger_example_pings', $count);
}

/**
 * Function to generate pong events and invoke hook_trigger_example().
 */
function trigger_example_pong() {
  $count = variable_get('trigger_example_pings', 0);

  // Invoke hook_trigger_example() with the pong operation.
  module_invoke_all('trigger_example', 'pong', $count);
  variable_set('trigger_example_pings', max(0, $count - 1));
}

/**
 * Implementation of hook_trigger_example().
 */
function trigger_example_trigger_example($op, $count) {

  // Our module is dependent on the trigger module but other modules that this
  // code get's copied into might not so it's a good idea to check first.
  if (!module_exists('trigger')) {
    break;
  }

  // Find any the ids of any actions associated with this hook/operation pair.
  if ($aids = _trigger_get_hook_aids('trigger_example', $op)) {

    // Setup the context for our trigger.
    $context = array(
      'hook' => 'trigger_example',
      'op' => $op,
      'count' => $count,
    );

    // Since we're not operating on an object we need to create a dummy.
    $dummy = new stdClass();
    foreach ($aids as $aid => $action_info) {
      actions_do($aid, $dummy, $context);
    }
  }
}

/**
* Implementation of hook_action_info_alter().
*
* None of the built-in actions will be enabled for our hook by default. We
* need to implement hook_action_info_alter() so that we can enable a couple.
*/
function trigger_example_action_info_alter(&$info) {
  if (isset($info['system_message_action']['hooks'])) {
    $info['system_message_action']['hooks']['trigger_example'] = array(
      'ping',
      'pong',
    );
  }
  if (isset($info['system_send_email_action']['hooks'])) {
    $info['system_send_email_action']['hooks']['trigger_example'] = array(
      'ping',
      'pong',
    );
  }
}

/**
 * A form to help fire our triggers.
 */
function trigger_example_form(&$form_state) {
  $form['help'] = array(
    '#type' => 'item',
    '#value' => format_plural(variable_get('trigger_example_pings', 0), 'There is only @count ping out there.', 'There are @count pings out there. Come on pong them back.'),
  );
  $form['ping'] = array(
    '#type' => 'submit',
    '#value' => t('Ping'),
  );
  if (variable_get('trigger_example_pings', 0)) {
    $form['pong'] = array(
      '#type' => 'submit',
      '#value' => t('Pong'),
    );
  }
  return $form;
}
function trigger_example_form_submit($form, &$form_state) {
  if ($form_state['values']['op'] == t('Ping')) {
    trigger_example_ping();
  }
  else {
    trigger_example_pong();
  }
}

/**
 * @} End of "defgroup trigger_example".
 */

Functions

Name	Description
trigger_example_action_info_alter	Implementation of hook_action_info_alter().
trigger_example_form	A form to help fire our triggers.
trigger_example_form_submit
trigger_example_help	Implementation of hook_help().
trigger_example_hook_info	Implementation of hook_hook_info().
trigger_example_menu	Implementation of hook_menu().
trigger_example_ping	Function to generate ping events and invoke hook_trigger_example().
trigger_example_pong	Function to generate pong events and invoke hook_trigger_example().
trigger_example_trigger_example	Implementation of hook_trigger_example().