except (ImproperArchiveTypeError, KeyError):

            return _('Unknown archive type')

        # archive cache

        from kallithea import CONFIG

        rev_name = cs.raw_id[:12]

        archive_name = '%s-%s%s' % (safe_str(repo_name.replace('/', '_')),

                                    safe_str(rev_name), ext)

        use_cached_archive = False  # defines if we use cached version of archive

        archive_cache_enabled = CONFIG.get('archive_cache_dir')

        if not subrepos and archive_cache_enabled:

            #check if we it's ok to write

            if not os.path.isdir(CONFIG['archive_cache_dir']):

                os.makedirs(CONFIG['archive_cache_dir'])

            cached_archive_path = os.path.join(CONFIG['archive_cache_dir'], archive_name)

            if os.path.isfile(cached_archive_path):

                log.debug('Found cached archive in %s' % cached_archive_path)

                fd, archive = None, cached_archive_path

                use_cached_archive = True

            else:

                log.debug('Archive %s is not yet cached' % (archive_name))

        if not use_cached_archive:

            # generate new archive

                fd, archive = tempfile.mkstemp()

                temp_stream = open(archive, 'wb')

                log.debug('Creating new temp archive in %s' % archive)

                cs.fill_archive(stream=temp_stream, kind=fileformat, subrepos=subrepos)

                temp_stream.close()

                if not subrepos and archive_cache_enabled:

                    #if we generated the archive and use cache rename that

                    log.debug('Storing new archive in %s' % cached_archive_path)

                    shutil.move(archive, cached_archive_path)

                    archive = cached_archive_path

        def get_chunked_archive(archive):

            stream = open(archive, 'rb')

            while True:

                data = stream.read(16 * 1024)

                if not data:

                    stream.close()

                    if fd:  # fd means we used temporary file

                        os.close(fd)

                    if not archive_cache_enabled:

                        log.debug('Destroing temp archive %s' % archive)

                        os.remove(archive)

                    break

                yield data

        # store download action

        action_logger(user=c.authuser,

                      action='user_downloaded_archive:%s' % (archive_name),

                      repo=repo_name, ipaddr=self.ip_addr, commit=True)

        response.content_disposition = str('attachment; filename=%s' % (archive_name))

        response.content_type = str(content_type)

        return get_chunked_archive(archive)

    @LoginRequired()

    @HasRepoPermissionAnyDecorator('repository.read', 'repository.write',