/**
  * Imports posts from the current master branch.
  *
  * @return boolean
  */
 public function import_master()
 {
     if (!$this->app->semaphore()->is_open()) {
         return $this->app->response()->error(new WP_Error('semaphore_locked', sprintf(__('%s : Semaphore is locked, import/export already in progress.', 'wordpress-github-sync'), 'Controller::import_master()')));
     }
     $this->app->semaphore()->lock();
     remove_action('save_post', array($this, 'export_post'));
     remove_action('save_post', array($this, 'delete_post'));
     $result = $this->app->import()->master();
     $this->app->semaphore()->unlock();
     if (is_wp_error($result)) {
         return $this->app->response()->error($result);
     }
     return $this->app->response()->success($result);
 }