107 lines
3.6 KiB
Python
107 lines
3.6 KiB
Python
# Copyright 2011 OpenStack Foundation
|
|
# 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
|
|
#
|
|
# http://www.apache.org/licenses/LICENSE-2.0
|
|
#
|
|
# 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.
|
|
|
|
"""
|
|
A filter middleware that inspects the requested URI for a version string
|
|
and/or Accept headers and attempts to negotiate an API controller to
|
|
return
|
|
"""
|
|
|
|
from oslo.config import cfg
|
|
|
|
from glance.api import versions
|
|
from glance.common import wsgi
|
|
import glance.openstack.common.log as logging
|
|
|
|
CONF = cfg.CONF
|
|
|
|
LOG = logging.getLogger(__name__)
|
|
|
|
|
|
class VersionNegotiationFilter(wsgi.Middleware):
|
|
|
|
def __init__(self, app):
|
|
self.versions_app = versions.Controller()
|
|
super(VersionNegotiationFilter, self).__init__(app)
|
|
|
|
def process_request(self, req):
|
|
"""Try to find a version first in the accept header, then the URL"""
|
|
msg = _("Determining version of request: %(method)s %(path)s"
|
|
" Accept: %(accept)s")
|
|
args = {'method': req.method, 'path': req.path, 'accept': req.accept}
|
|
LOG.debug(msg % args)
|
|
|
|
# If the request is for /versions, just return the versions container
|
|
#TODO(bcwaldon): deprecate this behavior
|
|
if req.path_info_peek() == "versions":
|
|
return self.versions_app
|
|
|
|
accept = str(req.accept)
|
|
if accept.startswith('application/vnd.openstack.images-'):
|
|
LOG.debug(_("Using media-type versioning"))
|
|
token_loc = len('application/vnd.openstack.images-')
|
|
req_version = accept[token_loc:]
|
|
else:
|
|
LOG.debug(_("Using url versioning"))
|
|
# Remove version in url so it doesn't conflict later
|
|
req_version = self._pop_path_info(req)
|
|
|
|
try:
|
|
version = self._match_version_string(req_version)
|
|
except ValueError:
|
|
LOG.debug(_("Unknown version. Returning version choices."))
|
|
return self.versions_app
|
|
|
|
req.environ['api.version'] = version
|
|
req.path_info = ''.join(('/v', str(version), req.path_info))
|
|
LOG.debug(_("Matched version: v%d"), version)
|
|
LOG.debug('new path %s' % req.path_info)
|
|
return None
|
|
|
|
def _match_version_string(self, subject):
|
|
"""
|
|
Given a string, tries to match a major and/or
|
|
minor version number.
|
|
|
|
:param subject: The string to check
|
|
:returns version found in the subject
|
|
:raises ValueError if no acceptable version could be found
|
|
"""
|
|
if subject in ('v1', 'v1.0', 'v1.1') and CONF.enable_v1_api:
|
|
major_version = 1
|
|
elif subject in ('v2', 'v2.0', 'v2.1', 'v2.2') and CONF.enable_v2_api:
|
|
major_version = 2
|
|
else:
|
|
raise ValueError()
|
|
|
|
return major_version
|
|
|
|
def _pop_path_info(self, req):
|
|
"""
|
|
'Pops' off the next segment of PATH_INFO, returns the popped
|
|
segment. Do NOT push it onto SCRIPT_NAME.
|
|
"""
|
|
path = req.path_info
|
|
if not path:
|
|
return None
|
|
while path.startswith('/'):
|
|
path = path[1:]
|
|
idx = path.find('/')
|
|
if idx == -1:
|
|
idx = len(path)
|
|
r = path[:idx]
|
|
req.path_info = path[idx:]
|
|
return r
|