fb_settings.inc in Drupal for Facebook 5

File

fb_settings.inc

<?php

// The URL will look something like fb_cb/NID/fb_cb_type/TYPE
// In the future, there may be additional parameters, like spoofing a session for anonymous visitors.
define('FB_SETTINGS_APP_NID', 'fb_cb');
define('FB_SETTINGS_PAGE_TYPE', 'fb_cb_type');
if (!is_array($conf)) {
  $conf = array();
}

// This allows us to test whether this file has been included
$conf['fb_settings_check'] = TRUE;
if ($nid = _fb_settings_parse_nid()) {

  // Ensure unique session for facebook app.
  $conf['session_inc'] = dirname(__FILE__) . '/fb_session.inc';
}
if (isset($_REQUEST['fb_sig']) && isset($_REQUEST['fb_sig_in_canvas'])) {

  // It's a facebook callback to an FBML page.
  // Force clean URLs.  Looks better on facebook, and helps us know
  // what to expect Note that we set our facebook callback to end in
  // "?q=" so clean URLs will work in a facebook app whether or not
  // they work locally
  $conf['clean_url'] = 1;

  // Force the admin theme to be our facebook theme.
  // TODO: find a way to make this configurable.  I.e. to support iframe apps.
  $conf['admin_theme'] = 'fb_fbml';

  // Filters will behave differently on facebook, so we cannot share the cache_filter table.

  /*** NO LONGER NECESSARY XXX
    if (!is_array($db_prefix))
  	if (isset($db_prefix))
  	  $db_prefix = array('default' => $db_prefix);
  	else
  	  $db_prefix = array();
    if (!isset($db_prefix['cache_filter']))
  	$db_prefix['cache_filter'] = 'fb_';
    ***/

  // Worth considering: use db_prefix to give facebook, or each app,
  // it's own set of users.
}

/**
 * Implementation of conf_url_rewrite
 * 
 * Defines the URL rewrite if not defined already.  If it is defined already,
 * or your using 118n modules, you should define a custom_url_rewrite in
 * settings.php which calls fb_canvas_url_rewrite in addition to any others
 * that need to be called.  The order will be important!
 */
if (!function_exists('custom_url_rewrite')) {
  function custom_url_rewrite($type, $path, $original) {
    return fb_settings_url_rewrite($type, $path, $original);
  }
}

/**
 * Rewrite URLs for facebook canvas pages.
 * 
 * Ideally, this function would live in fb_canvas.module and only be
 * set when serving canvas pages.  However, it gets called before
 * modules are loaded.  So it must live here.
 */
function fb_settings_url_rewrite($type, $path, $original) {

  //dpm(func_get_args(), 'fb_canvas_url_rewrite');
  $prefixes = array(
    FB_SETTINGS_APP_NID,
    FB_SETTINGS_PAGE_TYPE,
  );
  if ($type == 'source') {

    // See if this is a request for us.
    if (strpos($path, FB_SETTINGS_APP_NID . '/') === 0) {

      // Too soon for arg() function.
      $args = explode('/', $path);
      while (count($args) && in_array($args[0], $prefixes)) {
        $key = array_shift($args);
        $value = array_shift($args);
        fb_settings($key, $value);

        // Store for use later.
      }
      if ($app_nid = fb_settings(FB_SETTINGS_APP_NID)) {
        if (count($args)) {
          $path = implode('/', $args);

          // remaining args
          $path = drupal_get_normal_path($path);
        }
        else {

          // frontpage
          $path = drupal_get_normal_path(variable_get('site_frontpage', 'node'));
        }
      }
    }
  }
  else {
    if ($type == 'alias') {
      if (function_exists('fb_canvas_is_fbml')) {
        $pre = '';
        if (fb_canvas_is_iframe()) {

          // Rewrite for iframes
          foreach ($prefixes as $prefix) {
            if ($value = fb_settings($prefix)) {
              $pre .= $prefix . '/' . fb_settings($prefix) . '/';
            }
          }
          $path = $pre . $path;
        }
        else {
          if (fb_canvas_is_fbml()) {

            // Rewrite for FBML

            //$path = $fb_app->canvas . '/' . $path; // old way

            // For now, same as for iframes, but may be different one day
            foreach ($prefixes as $prefix) {
              if ($value = fb_settings($prefix)) {
                $pre .= $prefix . '/' . fb_settings($prefix) . '/';
              }
            }
            $path = $pre . $path;
          }
        }
      }
    }
  }
  return $path;
}
function fb_settings($key, $value = NULL) {
  static $cache = array();
  if (isset($value)) {
    $cache[$key] = $value;
  }
  return $cache[$key];
}

/**
 * Parse the application nid from the URL.  This may be called before
 * custom_url_rewrite, so we can't count on fb_settings() to return the value.
 */
function _fb_settings_parse_nid() {
  if (isset($_GET['q'])) {
    $path = $_GET['q'];
    if (strpos($path, FB_SETTINGS_APP_NID . '/') === 0) {

      // Too soon for arg() function.
      $args = explode('/', $path);
      return $args[1];
    }
  }
}

Functions

Name	Description
fb_settings
fb_settings_url_rewrite	Rewrite URLs for facebook canvas pages.
_fb_settings_parse_nid	Parse the application nid from the URL. This may be called before custom_url_rewrite, so we can't count on fb_settings() to return the value.

Constants

Name	Description
FB_SETTINGS_APP_NID
FB_SETTINGS_PAGE_TYPE