public function plugin_statistics_service_usage($params)
 {
     require_once 'MediawikiDao.class.php';
     $dao = new MediawikiDao();
     $project_manager = ProjectManager::instance();
     $start_date = $params['start_date'];
     $end_date = $params['end_date'];
     $number_of_page = array();
     $number_of_page_between_two_dates = array();
     $number_of_page_since_a_date = array();
     foreach ($project_manager->getProjectsByStatus(Project::STATUS_ACTIVE) as $project) {
         if ($project->usesService('plugin_mediawiki')) {
             $number_of_page[] = $dao->getMediawikiPagesNumberOfAProject($project);
             $number_of_page_between_two_dates[] = $dao->getModifiedMediawikiPagesNumberOfAProjectBetweenStartDateAndEndDate($project, $start_date, $end_date);
             $number_of_page_since_a_date[] = $dao->getCreatedPagesNumberSinceStartDate($project, $start_date);
         }
     }
     $params['csv_exporter']->buildDatas($number_of_page, "Mediawiki Pages");
     $params['csv_exporter']->buildDatas($number_of_page_between_two_dates, "Modified Mediawiki pages");
     $params['csv_exporter']->buildDatas($number_of_page_since_a_date, "Number of created Mediawiki pages since start date");
 }