globalredirect.module in Global Redirect 5

The Global Redirect module redirects for all paths which have aliases but are not using the aliases which reduces the risk of duplicate content.

File

globalredirect.module

<?php

/**
 * @file
 * The Global Redirect module redirects for all paths which have aliases but are not using the aliases which reduces the risk of duplicate content.
 */
define('GLOBALREDIRECT_FEATURE_DISABLED', -1);
define('GLOBALREDIRECT_TRAILINGZERO_TAXTERM', 1);
define('GLOBALREDIRECT_TRAILINGZERO_ALL', 2);
define('GLOBALREDIRECT_NONCLEAN2CLEAN_ENABLED', 1);
define('GLOBALREDIRECT_DESLASH_ENABLED', 1);
define('GLOBALREDIRECT_CASE_SENSITIVE_URLS_ENABLED', 1);

/**
 * Implementation of hook_help().
 */
function globalredirect_help($section) {
  switch ($section) {
    case 'admin/modules#description':
      return t('This module will do a 301 redirect for all nodes which have an alias but are not using that alias.');
  }
}

/**
 * Implementation of hook_init().
 */
function globalredirect_init() {

  /**
   * We need to do a test to make sure we only clean up URL's for the main request. This stops modules such as
   * the Ad Module which had its own script in its folder doing a bootstrap which invoked hook_init and caused some banners to get "cleaned up"
   * See issues: http://drupal.org/node/205810 and http://drupal.org/node/278615
   */
  if ($_SERVER['SCRIPT_NAME'] != $GLOBALS['base_path'] . 'index.php') {
    return FALSE;
  }

  /**
   * If the site is in offline mode there is little point doing any of this as you might end up redirecting to a 503.
   */
  if (variable_get('site_offline', 0) == 1) {
    return FALSE;
  }

  /**
   * We need to make sure this hook only fires in certain conditions:
   *   1) If the 'drupal_get_path' function exists. Sometimes hook_init gets called twice, the first call hasn't included path.inc.
   *   2) If the callback associated with the request is accessible - this stops the user learning hidden/private url aliases.
   *   3) If there is a request. There is no point checking the REAL frontpage for an alias.
   *   4) If the $_POST is empty. The problem which arises here is if a form posts to an source path rather than the alias. GlobalRedirect sometimes interrupts the post and redirects to the alias instead.
   */
  if (function_exists('drupal_get_path_alias') && function_exists('_menu_item_is_accessible') && _menu_item_is_accessible(menu_get_active_item()) && isset($_REQUEST['q']) && empty($_POST)) {

    // Store the destination from the $_REQUEST as it breaks things if we leave it in - restore it at the end...
    if (isset($_REQUEST['destination'])) {
      $destination = $_REQUEST['destination'];
      unset($_REQUEST['destination']);
    }

    // Use drupal_get_normal_path() to allow custom_url_reqwrite to effect $q
    $q = drupal_get_normal_path($_REQUEST['q']);

    // Get the Query String (minus the 'q'). If none set, set to NULL
    $query_string = drupal_query_string_encode($_GET, array(
      'q',
    ));
    if (empty($query_string)) {
      $query_string = NULL;
    }

    // If current path is also the frontpage, redirect to http://www.example.com.
    if (!empty($q) && drupal_is_front_page()) {
      drupal_goto('', $query_string, NULL, 301);
    }

    // Trim any trailing slash off the end (eg, 'node/1/' to 'node/1')
    $redirect_slash = variable_get('globalredirect_deslash', GLOBALREDIRECT_DESLASH_ENABLED) == GLOBALREDIRECT_DESLASH_ENABLED;
    $request = $redirect_slash ? trim($_REQUEST['q'], '/') : $_REQUEST['q'];

    // Optional stripping of "/0". Defaultly disabled
    switch (variable_get('globalredirect_trailingzero', GLOBALREDIRECT_FEATURE_DISABLED)) {
      case GLOBALREDIRECT_TRAILINGZERO_TAXTERM:

        // If 'taxonomy/term/*' only. If not, break out.
        if (drupal_substr($request, 0, 14) != 'taxonomy/term/') {
          break;
        }

      // If it is, fall through to general trailing zero method
      case GLOBALREDIRECT_TRAILINGZERO_ALL:

        // If last 2 characters of URL are /0 then trim them off
        if (drupal_substr($request, -2) == '/0') {
          $request = rtrim($request, '/0');
        }
    }

    // Check the path (eg, node/123) for an request.
    $alias = drupal_get_path_alias($request);

    // Alias case sensitivity check. If there is an alias from the previous lookup, do a query to test for case.
    if ($alias && variable_get('globalredirect_case_sensitive_urls', GLOBALREDIRECT_CASE_SENSITIVE_URLS_ENABLED) == GLOBALREDIRECT_CASE_SENSITIVE_URLS_ENABLED) {
      $alias_sensitive = db_result(db_query("SELECT dst FROM {url_alias} WHERE dst = '%s'", $alias));
      if ($alias_sensitive && $alias != $alias_sensitive) {

        // There is a match and there is a difference in case.
        $alias = $alias_sensitive;
      }
    }

    // If alias is different to the request, redirect...
    if ($alias != $_REQUEST['q']) {
      drupal_goto($alias, $query_string, NULL, 301);
    }

    // If the trimmed request differs to the request then redirect (basically, de-slash the source path).
    if ($redirect_slash && $request != $_REQUEST['q']) {
      drupal_goto($request, $query_string, NULL, 301);
    }

    // If no alias was returned, the final check is to direct non-clean to clean - if clean is enabled.
    if (variable_get('globalredirect_nonclean2clean', GLOBALREDIRECT_NONCLEAN2CLEAN_ENABLED) == GLOBALREDIRECT_NONCLEAN2CLEAN_ENABLED && (bool) variable_get('clean_url', 0) && strpos(request_uri(), '?q=')) {
      drupal_goto($request, $query_string, NULL, 301);
    }

    // Restore the destination from earlier so its available in other places.
    if (isset($destination)) {
      $_REQUEST['destination'] = $destination;
    }
  }
}

Functions

Name	Description
globalredirect_help	Implementation of hook_help().
globalredirect_init	Implementation of hook_init().

Constants

Name	Description
GLOBALREDIRECT_CASE_SENSITIVE_URLS_ENABLED
GLOBALREDIRECT_DESLASH_ENABLED
GLOBALREDIRECT_FEATURE_DISABLED	@file The Global Redirect module redirects for all paths which have aliases but are not using the aliases which reduces the risk of duplicate content.
GLOBALREDIRECT_NONCLEAN2CLEAN_ENABLED
GLOBALREDIRECT_TRAILINGZERO_ALL
GLOBALREDIRECT_TRAILINGZERO_TAXTERM