eZ\Publish\Core\MVC\Symfony\Cache\Http\LocationAwareStore::purgeLocation PHP Method

    private function purgeLocation($locationId)
    {
        $fs = $this->getFilesystem();
        $locationCacheDir = $this->getLocationCacheDir($locationId);
        if ($fs->exists($locationCacheDir)) {
            // 1. Copy cache files to stale cache dir
            // 2. Place a lock file indicating to use the stale cache
            // 3. Remove real cache dir
            // 4. Remove lock file
            // 5. Remove stale cache dir
            // Note that there is no need to remove the meta-file
            $staleCacheDir = str_replace(static::LOCATION_CACHE_DIR, static::LOCATION_STALE_CACHE_DIR, $locationCacheDir);
            $fs->mkdir($staleCacheDir);
            $fs->mirror($locationCacheDir, $staleCacheDir);
            $lockFile = $this->getLocationCacheLockName($locationId);
            file_put_contents($lockFile, getmypid());
            try {
                // array of removal is in reverse order on purpose since remove() starts from the end.
                $fs->remove(array($staleCacheDir, $lockFile, $locationCacheDir));
                return true;
            } catch (IOException $e) {
                // Log the error in the standard error log and at least try to remove the lock file
                error_log($e->getMessage());
                @unlink($lockFile);
                return false;
            }
        }
        return false;
    }