fb_tab.module in Drupal for Facebook 7.3

This module provides support for "Profile Tabs" that can be added to facebook pages (no longer allowed for user profiles).

http://developers.facebook.com/docs/guides/canvas/#tabs

File

fb_tab.module

<?php

/**
 * @file
 *
 * This module provides support for "Profile Tabs" that can be added to
 * facebook pages (no longer allowed for user profiles).
 *
 * http://developers.facebook.com/docs/guides/canvas/#tabs
 *
 */

// hook_fb
define('FB_TAB_HOOK', 'fb_tab');

//// Hook_fb_tab operations
define('FB_TAB_OP_VIEW', 'fb_tab_view');
define('FB_TAB_OP_FORM', 'fb_tab_form');
define('FB_TAB_PATH_VIEW', 'fb_tab/view');
define('FB_TAB_PATH_FORM', 'fb_tab/config');
define('FB_TAB_PATH_FORM_ARGS', 2);
define('FB_TAB_PATH_ADDED', 'fb_tab/added');

// user redirected here after adding page tab.
define('FB_TAB_PATH_ADDED_ARGS', 2);
define('FB_TAB_VAR_PROCESS_IFRAME', 'fb_tab_process_iframe');
define('FB_TAB_VAR_PROCESS_ABSOLUTE', 'fb_tab_process_absolute_links');
define('FB_TAB_VAR_PROCESS_TO_CANVAS', 'fb_tab_process_to_canvas');
define('FB_TAB_PROCESS_IFRAME_NONE', 'none');
define('FB_TAB_PROCESS_IFRAME_TO_CANVAS', 'canvas');
define('FB_TAB_PROCESS_IFRAME_TO_TAB_VIA_APP_DATA', 'app_data');
function fb_tab_menu() {
  $items = array();
  $items[FB_TAB_PATH_VIEW] = array(
    'page callback' => 'fb_tab_view',
    'access arguments' => array(
      'access content',
    ),
    'type' => MENU_CALLBACK,
  );
  $items[FB_TAB_PATH_FORM] = array(
    'title' => 'Configure Tabs',
    'page callback' => 'fb_tab_pages',
    'access arguments' => array(
      'access content',
    ),
    'type' => MENU_CALLBACK,
  );
  $items[FB_TAB_PATH_FORM . '/%'] = array(
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      'fb_tab_config_form',
      FB_TAB_PATH_FORM_ARGS,
    ),
    'access arguments' => array(
      'access content',
    ),
    'type' => MENU_CALLBACK,
  );
  $items[FB_TAB_PATH_ADDED . '/%fb'] = array(
    'page callback' => 'fb_tab_added',
    'access arguments' => array(
      'access content',
    ),
    'page arguments' => array(
      FB_TAB_PATH_ADDED_ARGS,
    ),
    'type' => MENU_CALLBACK,
  );

  // Admin pages
  $items[FB_PATH_ADMIN . '/fb_tab'] = array(
    'title' => 'Page Tabs',
    'description' => 'Configure Tabs',
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      'fb_tab_admin_settings',
    ),
    'access arguments' => array(
      FB_PERM_ADMINISTER,
    ),
    'file' => 'fb_tab.admin.inc',
    'type' => MENU_LOCAL_TASK,
  );
  return $items;
}

/*
 * Implements hook_custom_theme().
 *
 * For tab pages we use app-specific theme.  For this function to succeed,
 * fb_tab.module must come after fb.module in the module weights (it is by
 * default).
 */
function fb_tab_custom_theme() {
  if (fb_is_tab()) {

    // Get our configuration settings.
    $config = _fb_tab_get_app_config($GLOBALS['_fb_app']);
    if ($custom_theme = $config['custom_theme']) {
      return $custom_theme;
    }
  }
}

/**
 * Implements hook_fb
 *
 * @param $op
 * @param $data -- data payload
 * @param $return
 */
function fb_tab_fb($op, $data, &$return) {
  $fb = isset($data['fb']) ? $data['fb'] : NULL;
  $fb_app = isset($data['fb_app']) ? $data['fb_app'] : NULL;
  if ($op == FB_OP_POST_INIT) {

    // Include our admin hooks.
    if (fb_is_fb_admin_page()) {
      require drupal_get_path('module', 'fb_tab') . '/fb_tab.admin.inc';
    }
    if (fb_is_tab()) {

      // Include our javascript.
      drupal_add_js(array(
        'fb_tab' => array(
          'fbu' => fb_facebook_user(),
          'uid' => $GLOBALS['user']->uid,
          'canvas' => $fb_app->canvas,
        ),
      ), 'setting');
      drupal_add_js(drupal_get_path('module', 'fb_tab') . '/fb_tab.js');
    }
  }
  elseif ($op == FB_OP_CURRENT_APP && fb_is_tab()) {
    if ($id = fb_settings(FB_SETTINGS_CB)) {

      // Using fb_url_rewrite.
      $fb_app = fb_get_app(array(
        'id' => $id,
      ));
      if (!$fb_app) {

        // DEPRECATED.  For backward compatibility, accept apikey in FB_SETTINGS_CB
        $fb_app = fb_get_app(array(
          'apikey' => $id,
        ));
      }
    }
    elseif ($id = fb_settings(FB_SETTINGS_ID)) {

      // New SDK includes ID when session is present.
      $fb_app = fb_get_app(array(
        'id' => $id,
      ));
    }
    elseif (isset($_REQUEST['fb_sig_api_key'])) {
      $return = fb_get_app(array(
        'apikey' => $_REQUEST['fb_sig_api_key'],
      ));
    }
    if ($fb_app) {
      $return = $fb_app;
    }
  }
  elseif ($op == FB_OP_INITIALIZE) {
    if (fb_is_tab()) {
      $config = _fb_tab_get_app_config($fb_app);

      // custom_theme handling moved to fb_tab_custom_theme().
      if (fb_settings(FB_SETTINGS_TYPE) == FB_SETTINGS_TYPE_PAGE_TAB && (variable_get(FB_TAB_VAR_PROCESS_IFRAME, TRUE) || variable_get(FB_TAB_VAR_PROCESS_ABSOLUTE, TRUE))) {

        // Process iframe
        $use_ob = TRUE;
      }
      else {
        $use_ob = FALSE;
      }

      // Hack to init the theme before _drupal_maintenance_theme initializes the wrong one.
      if (variable_get('maintenance_mode', FALSE)) {
        $dummy = theme('dummy');
      }

      // Store entire page in output buffer. Will post-process on exit.
      if ($use_ob) {
        ob_start();
        $GLOBALS['fb_tab_post_process'] = TRUE;
      }

      // If path is fb_tab/view, we may actually show some other menu item.
      if (arg(0) == 'fb_tab' && arg(1) == 'view') {

        // Do not override fb_tab/config.
        $sr = $fb
          ->getSignedRequest();
        if (!empty($sr['app_data']) && !empty($config['app_data_is_path'])) {
          $path = $sr['app_data'];
        }
        elseif ($sr['page'] && $sr['page']['liked'] && $config['profile_tab_url_liked']) {
          $path = $config['profile_tab_url_liked'];
        }
        else {
          $path = $config['profile_tab_url'];
        }

        // Enable token replacement from signed request.
        $path = token_replace($path, array(), array(
          'clear' => TRUE,
        ));

        // <front> is a special path
        $path = str_replace('<front>', variable_get('site_frontpage', 'node'), $path);
        if ($path && $path != FB_TAB_PATH_VIEW) {

          // Tell Drupal what to really render.
          menu_set_active_item(drupal_get_normal_path($path));
        }
      }
    }
  }
  elseif ($op == FB_OP_EXIT && fb_is_tab()) {
    if (isset($GLOBALS['fb_tab_post_process']) && $GLOBALS['fb_tab_post_process']) {
      $output = ob_get_contents();
      ob_end_clean();
      include_once drupal_get_path('module', 'fb') . '/fb.process.inc';
      $process = variable_get(FB_TAB_VAR_PROCESS_IFRAME, FB_TAB_PROCESS_IFRAME_TO_CANVAS);
      if ($process == FB_TAB_PROCESS_IFRAME_TO_CANVAS) {
        $to_canvas = $fb_app->canvas;
      }
      else {
        $to_canvas = FALSE;
      }
      $to_page = FALSE;
      $page = NULL;
      if ($process == FB_TAB_PROCESS_IFRAME_TO_TAB_VIA_APP_DATA) {
        if ($page_id = fb_settings(FB_SETTINGS_PAGE_ID)) {
          $page = fb_graph($page_id);
          if (!empty($page['link'])) {

            // @TODO: $page['link'] may change protocol from https to http.
            $to_page = $page['link'] . "?v=app_" . fb_settings(FB_SETTINGS_ID);
          }
        }
      }
      if (fb_settings(FB_SETTINGS_TYPE) == FB_SETTINGS_TYPE_PAGE_TAB) {

        // Process iframe
        $output = fb_process($output, array(
          'add_target' => '_top',
          'absolute_links' => variable_get(FB_TAB_VAR_PROCESS_ABSOLUTE, TRUE),
          'relative_links' => variable_get(FB_TAB_VAR_PROCESS_IFRAME, TRUE),
          'to_canvas' => $to_canvas,
          'to_page' => $to_page,
        ));
      }
      elseif (fb_settings(FB_SETTINGS_TYPE) == FB_SETTINGS_TYPE_PROFILE) {

        // Process FBML (deprecated)
        $output = fb_process($output, array(
          'add_target' => FALSE,
          'absolute_links' => TRUE,
          'to_canvas' => $to_canvas,
        ));
      }
      if (isset($output)) {
        print $output;
      }
    }
    $destination = $return;
    if ($destination) {

      // A normal redirect will affect only our iframe.
      // We must instead send the user to our page on facebook.com.
      if ($process == FB_TAB_PROCESS_IFRAME_TO_TAB_VIA_APP_DATA) {
        if (!empty($to_page)) {
          $url = fb_iframe_fix_url($destination, $to_page . '&app_data=');

          // It's not ideal to call this here, as doing so prevents other
          // hook_exits from running.  However there's no later
          // opportunity to change where Drupal would send us.
          fb_iframe_redirect($url);
        }
      }
    }
  }
}

/**
 * Implements fb_tab_form_alter.
 */
function fb_tab_form_alter(&$form, &$form_state, $form_id) {
  if (isset($form['fb_app_data']) && is_array($form['fb_app_data'])) {

    // Add our settings to the fb_app edit form.

    //require 'fb_canvas.admin.inc';
    fb_tab_admin_form_alter($form, $form_state, $form_id);
  }
  if (!empty($_REQUEST['signed_request']) && empty($form['signed_request']) && fb_is_tab()) {

    // Facebook will pass us the important signed_request.
    // When we submit a form, that data will be lost unless we explicitly include it in the form.
    $form['signed_request'] = array(
      '#type' => 'hidden',
      '#value' => $_REQUEST['signed_request'],
    );
  }
}

/**
 * Helper returns configuration for this module, on a per-app basis.
 */
function _fb_tab_get_app_config($fb_app) {
  $fb_app_data = fb_get_app_data($fb_app);
  $config = isset($fb_app_data['fb_tab']) ? $fb_app_data['fb_tab'] : array();

  // Merge in defaults
  $config += array(
    'custom_theme' => NULL,
    'tab_default_name' => isset($fb_app->title) ? $fb_app->title : NULL,
    'profile_tab_url' => NULL,
    'profile_tab_url_liked' => NULL,
    'app_data_is_path' => TRUE,
    'edit_url' => FB_TAB_PATH_FORM,
  );
  return $config;
}

/**
 * Another module provides the contents of the tab depending
 * on the context that we give it (who is calling it, etc.)
 */
function fb_tab_view() {
  $fb_app = $GLOBALS['_fb_app'];
  $fb = $GLOBALS['_fb'];
  $profile_id = fb_settings(FB_SETTINGS_CB_PAGE);
  $config = fb_tab_get_page_config($fb_app, $profile_id);
  $sr = $fb
    ->getSignedRequest();
  $data = array(
    'fb_app' => $fb_app,
    'fb' => $fb,
    'profile_id' => $profile_id,
    'config' => isset($config['data']) ? $config['data'] : NULL,
    'page' => isset($sr['page']) ? $sr['page'] : NULL,
  );
  $content = fb_invoke(FB_TAB_OP_VIEW, $data, array(), FB_TAB_HOOK);
  return drupal_render($content);
}

/**
 * Build the tab config form. Invokes hook_fb_tab() to get the custom settings.
 */
function fb_tab_config_form($form_state, $profile_id) {
  $fb_app = $GLOBALS['_fb_app'];
  $fb = $GLOBALS['_fb'];
  $config = fb_tab_get_page_config($fb_app, $profile_id);
  $sr = $fb
    ->getSignedRequest();
  $data = array(
    'fb_app' => $fb_app,
    'fb' => $fb,
    'profile_id' => $profile_id,
    'config' => isset($config['data']) ? $config['data'] : NULL,
    'page' => $sr['page'],
  );
  try {

    //$fbu = fb_facebook_user($fb);
    $fbu = fb_require_authorization($fb);
    $page_info = $fb
      ->api($profile_id, array(
      'access_token' => fb_get_token($fb),
    ));
    $admin_info = fb_fql_query($fb, "SELECT uid, type FROM page_admin WHERE uid={$fbu} AND page_id={$profile_id}");

    // FQL not SQL, no {curly_brackets}
    // @TODO: if not page admin, prompt user to login or deny access.
    $form = array(
      'info' => array(
        '#type' => 'markup',
        '#value' => t('Tab settings for <a href="!href">%page</a>', array(
          '!href' => $page_info['link'],
          '%page' => $page_info['name'],
        )),
        '#prefix' => '<h3>',
        '#suffix' => '</h3>',
        '#weight' => -99,
      ),
      'label' => array(
        '#type' => 'value',
        '#value' => $fb_app->label,
      ),
      'profile_id' => array(
        '#type' => 'value',
        '#value' => $profile_id,
      ),
      'data' => array(
        // Modules will add their fields here.
        '#tree' => TRUE,
      ),
      'submit' => array(
        '#type' => 'submit',
        '#value' => t('Submit'),
        '#weight' => 90,
      ),
    );
    if (isset($config['fb_tab_id'])) {
      $form['fb_tab_id'] = array(
        '#type' => 'value',
        '#value' => $config['fb_tab_id'],
      );
    }
    $form['data'] = fb_invoke(FB_TAB_OP_FORM, $data, $form['data'], FB_TAB_HOOK);

    //print('<pre>' . print_r($data, 1) . '</pre>'); flush();

    //print(print_r($content, 1)); flush();
    return $form;
  } catch (Exception $e) {
    fb_log_exception($e, t('Failed to get details for facebook page %profile_id', array(
      '%profile_id' => $profile_id,
    )));
    return array(
      'error' => array(
        '#value' => t('Unable to set properties.'),
      ),
    );
  }
}

/**
 * Submit handler for tab config form.
 */
function fb_tab_config_form_submit($form, &$form_state) {
  if ($profile_id = $form_state['values']['profile_id']) {
    fb_tab_write_config($form_state['values']);
    $data = fb_fql_query($GLOBALS['_fb'], "SELECT page_id, name, pic_small, page_url, type FROM page WHERE page_id={$profile_id}");

    // FQL, no {curly_brackets}
    drupal_set_message(t('The tab settings for <a href="!url">%page</a> have been updated.', array(
      '!url' => $data[0]['page_url'],
      '%page' => $data[0]['name'],
    )));
  }
}

/*
 * Store configuration data for a tab by application.
 */
function fb_tab_write_config(&$row) {
  if (!isset($row['created'])) {
    $row['created'] = time();
  }
  $row['data'] = serialize($row['data']);
  return drupal_write_record('fb_tab', $row, isset($row['fb_tab_id']) ? array(
    'fb_tab_id',
  ) : NULL);
}

/*
 * Return configuration of a tab by application (access via 'label') and page ID.
 * Page ID exists because an app can present different views on different pages.
 */
function fb_tab_get_page_config($fb_app, $profile_id) {
  $row = db_query("SELECT * FROM {fb_tab} WHERE label = :label AND profile_id = :pid", array(
    ':label' => $fb_app->label,
    ':pid' => $profile_id,
  ))
    ->fetchAssoc();
  if ($row) {
    $row['data'] = unserialize($row['data']);
    return $row;
  }
  else {
    return array();
  }
}

/**
 * Drupal menu callback.  User has added a tab to one of their pages.
 */
function fb_tab_added($fb_app) {

  //dpm($_REQUEST, __FUNCTION__); // debug what facebook has passed to us
  if (empty($_REQUEST['tabs_added'])) {

    // Sanity check.
    drupal_set_message(t('Failed to add tab to facebook page.'), 'error');
    return t('Failed to add tab to facebook page.');
  }
  foreach ($_REQUEST['tabs_added'] as $page_id => $added) {

    // TODO use batch graph api.
    $graph = fb_graph($page_id, array());
    watchdog('fb_tab', "Facebook application %label (%app_id) added to page %name (%page_id)", array(
      '%label' => $fb_app->label,
      '%app_id' => $fb_app->id,
      '%name' => $graph['name'],
      '%page_id' => $graph['id'],
    ));
  }

  // Redirect user to the page tab they've added.
  if ($graph['link']) {

    // This undocumented format seems to be the right URL for a page tab.
    $url = $graph['link'] . '?sk=app_' . $fb_app->id;
    drupal_goto($url);
  }

  // If drupal_goto succeeds, user will not see this.
  return t('Added application to Facebook page.');
}

/**
 * This page callback will show the user a list of pages they have authority
 * to configure.
 */
function fb_tab_pages() {
  if ($fbu = fb_facebook_user()) {

    // @TODO: broken on facebook's end??? this query used to work.
    $result = fb_fql_query($GLOBALS['_fb'], "SELECT page_id, name, pic_small, page_url, type FROM page WHERE has_added_app=1 AND page_id IN (SELECT page_id FROM page_admin WHERE uid={$fbu})");

    // FQL, no {curly_brackets}
    if (count($result)) {
      $output['pages'] = array(
        '#prefix' => '<ul>',
        '#suffix' => '</ul>',
      );
      foreach ($result as $data) {
        $output['pages'][$data['page_id']] = array(
          '#value' => l($data['name'], fb_tab_config_url($data['page_id'], array(
            'fb_canvas' => fb_is_canvas(),
          ))),
          '#prefix' => '<li>',
          '#suffix' => '</li>',
        );
      }
      $output['intro'] = array(
        '#value' => t('Select one of your pages to configure:'),
        '#prefix' => '<p>',
        '#suffix' => '</p>',
      );
    }
    else {
      $output['intro'] = array(
        '#value' => t('Found no pages to configure.'),
        '#prefix' => '<p>',
        '#suffix' => '</p>',
      );
    }
    return drupal_render($output);
  }
  else {
    fb_access_denied();
  }
}

/**
 * Provides the URL of the settings page for a given facebook page.
 */
function fb_tab_config_url($profile_id = NULL, $options = array()) {
  if (!$profile_id) {
    $profile_id = fb_settings(FB_SETTINGS_CB_PAGE);
  }
  return url(FB_TAB_PATH_FORM . '/' . $profile_id, $options);
}

Functions

Name	Description
fb_tab_added	Drupal menu callback. User has added a tab to one of their pages.
fb_tab_config_form	Build the tab config form. Invokes hook_fb_tab() to get the custom settings.
fb_tab_config_form_submit	Submit handler for tab config form.
fb_tab_config_url	Provides the URL of the settings page for a given facebook page.
fb_tab_custom_theme
fb_tab_fb	Implements hook_fb
fb_tab_form_alter	Implements fb_tab_form_alter.
fb_tab_get_page_config
fb_tab_menu
fb_tab_pages	This page callback will show the user a list of pages they have authority to configure.
fb_tab_view	Another module provides the contents of the tab depending on the context that we give it (who is calling it, etc.)
fb_tab_write_config
_fb_tab_get_app_config	Helper returns configuration for this module, on a per-app basis.

Constants

Name	Description
FB_TAB_HOOK
FB_TAB_OP_FORM
FB_TAB_OP_VIEW
FB_TAB_PATH_ADDED
FB_TAB_PATH_ADDED_ARGS
FB_TAB_PATH_FORM
FB_TAB_PATH_FORM_ARGS
FB_TAB_PATH_VIEW
FB_TAB_PROCESS_IFRAME_NONE
FB_TAB_PROCESS_IFRAME_TO_CANVAS
FB_TAB_PROCESS_IFRAME_TO_TAB_VIA_APP_DATA
FB_TAB_VAR_PROCESS_ABSOLUTE
FB_TAB_VAR_PROCESS_IFRAME
FB_TAB_VAR_PROCESS_TO_CANVAS