Piwik\Archive::getSiteIdsThatAreRequestedInThisArchiveButWereNotInvalidatedYet PHP Method

    private function getSiteIdsThatAreRequestedInThisArchiveButWereNotInvalidatedYet()
    {
        if (is_null(self::$cache)) {
            self::$cache = Cache::getTransientCache();
        }
        $id = 'Archive.SiteIdsOfRememberedReportsInvalidated';
        if (!self::$cache->contains($id)) {
            self::$cache->save($id, array());
        }
        $siteIdsAlreadyHandled = self::$cache->fetch($id);
        $siteIdsRequested = $this->params->getIdSites();
        foreach ($siteIdsRequested as $index => $siteIdRequested) {
            $siteIdRequested = (int) $siteIdRequested;
            if (in_array($siteIdRequested, $siteIdsAlreadyHandled)) {
                unset($siteIdsRequested[$index]);
                // was already handled previously, do not do it again
            } else {
                $siteIdsAlreadyHandled[] = $siteIdRequested;
                // we will handle this id this time
            }
        }
        self::$cache->save($id, $siteIdsAlreadyHandled);
        return $siteIdsRequested;
    }