Source code for glance.api.middleware.gzip

# Copyright 2013 Red Hat, Inc.
# All Rights Reserved.
#    Licensed under the Apache License, Version 2.0 (the "License"); you may
#    not use this file except in compliance with the License. You may obtain
#    a copy of the License at
#    Unless required by applicable law or agreed to in writing, software
#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
#    License for the specific language governing permissions and limitations
#    under the License.

Use gzip compression if the client accepts it.

import re

from oslo_log import log as logging

from glance.common import wsgi
from glance.i18n import _LI

LOG = logging.getLogger(__name__)

[docs]class GzipMiddleware(wsgi.Middleware): re_zip = re.compile(r'\bgzip\b') def __init__(self, app):"Initialized gzip middleware")) super(GzipMiddleware, self).__init__(app)
[docs] def process_response(self, response): request = response.request accept_encoding = request.headers.get('Accept-Encoding', '') if # NOTE(flaper87): Webob removes the content-md5 when # app_iter is called. We'll keep it and reset it later checksum = response.headers.get("Content-MD5") # NOTE(flaper87): We'll use lazy for images so # that they can be compressed without reading # the whole content in memory. Notice that using # lazy will set response's content-length to 0. content_type = response.headers.get("Content-Type", "") lazy = content_type == "application/octet-stream" # NOTE(flaper87): Webob takes care of the compression # process, it will replace the body either with a # compressed body or a generator - used for lazy com # pression - depending on the lazy value. # # Webob itself will set the Content-Encoding header. response.encode_content(lazy=lazy) if checksum: response.headers['Content-MD5'] = checksum return response