Jason Kölker 73f41d370e Add API v2 support
* Implements BP v2-api-melange-integration
* Adds v2 Plugin specification
* Refactors SQLAlchemy usage for multiple BASE's

Change-Id: I45f008f181c18269afdfe4a9b589a7c5ae56d225
2012-06-11 10:36:10 -05:00

209 lines
6.6 KiB
Python

# Copyright (c) 2012 OpenStack, LLC.
#
# 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.
import logging
import webob.exc
from quantum.common import exceptions
from quantum.api.v2 import resource as wsgi_resource
from quantum.common import utils
from quantum.api.v2 import views
LOG = logging.getLogger(__name__)
XML_NS_V20 = 'http://openstack.org/quantum/api/v2.0'
FAULT_MAP = {exceptions.NotFound: webob.exc.HTTPNotFound,
exceptions.InUse: webob.exc.HTTPConflict,
exceptions.StateInvalid: webob.exc.HTTPBadRequest}
def fields(request):
"""
Extracts the list of fields to return
"""
return [v for v in request.GET.getall('fields') if v]
def filters(request):
"""
Extracts the filters from the request string
Returns a dict of lists for the filters:
check=a&check=b&name=Bob&verbose=True&verbose=other
becomes
{'check': [u'a', u'b'], 'name': [u'Bob']}
"""
res = {}
for key in set(request.GET):
if key in ('verbose', 'fields'):
continue
values = [v for v in request.GET.getall(key) if v]
if values:
res[key] = values
return res
def verbose(request):
"""
Determines the verbose fields for a request
Returns a list of items that are requested to be verbose:
check=a&check=b&name=Bob&verbose=True&verbose=other
returns
[True]
and
check=a&check=b&name=Bob&verbose=other
returns
['other']
"""
verbose = [utils.boolize(v) for v in request.GET.getall('verbose') if v]
# NOTE(jkoelker) verbose=<bool> trumps all other verbose settings
if True in verbose:
return True
elif False in verbose:
return False
return verbose
class Controller(object):
def __init__(self, plugin, collection, resource, params):
self._plugin = plugin
self._collection = collection
self._resource = resource
self._params = params
self._view = getattr(views, self._resource)
def _items(self, request):
"""Retrieves and formats a list of elements of the requested entity"""
kwargs = {'filters': filters(request),
'verbose': verbose(request),
'fields': fields(request)}
obj_getter = getattr(self._plugin, "get_%s" % self._collection)
obj_list = obj_getter(request.context, **kwargs)
return {self._collection: [self._view(obj) for obj in obj_list]}
def _item(self, request, id):
"""Retrieves and formats a single element of the requested entity"""
kwargs = {'verbose': verbose(request),
'fields': fields(request)}
obj_getter = getattr(self._plugin,
"get_%s" % self._resource)
obj = obj_getter(request.context, id, **kwargs)
return {self._resource: self._view(obj)}
def index(self, request):
"""Returns a list of the requested entity"""
return self._items(request)
def show(self, request, id):
"""Returns detailed information about the requested entity"""
return self._item(request, id)
def create(self, request, body=None):
"""Creates a new instance of the requested entity"""
body = self._prepare_request_body(body, allow_bulk=True)
obj_creator = getattr(self._plugin,
"create_%s" % self._resource)
kwargs = {self._resource: body}
obj = obj_creator(request.context, **kwargs)
return {self._resource: self._view(obj)}
def delete(self, request, id):
"""Deletes the specified entity"""
obj_deleter = getattr(self._plugin,
"delete_%s" % self._resource)
obj_deleter(request.context, id)
def update(self, request, id, body=None):
"""Updates the specified entity's attributes"""
obj_updater = getattr(self._plugin,
"update_%s" % self._resource)
kwargs = {self._resource: body}
obj = obj_updater(request.context, id, **kwargs)
return {self._resource: self._view(obj)}
def _prepare_request_body(self, body, allow_bulk=False):
""" verifies required parameters are in request body.
Parameters with default values are considered to be
optional.
body argument must be the deserialized body
"""
if not body:
raise webob.exc.HTTPBadRequest(_("Resource body required"))
body = body or {self._resource: {}}
if self._collection in body and allow_bulk:
bulk_body = [self._prepare_request_body({self._resource: b})
if self._resource not in b
else self._prepare_request_body(b)
for b in body[self._collection]]
if not bulk_body:
raise webob.exc.HTTPBadRequest(_("Resources required"))
return {self._collection: bulk_body}
elif self._collection in body and not allow_bulk:
raise webob.exc.HTTPBadRequest("Bulk operation not supported")
res_dict = body.get(self._resource)
if res_dict is None:
msg = _("Unable to find '%s' in request body") % self._resource
raise webob.exc.HTTPBadRequest(msg)
for param in self._params:
param_value = res_dict.get(param['attr'], param.get('default'))
if param_value is None:
msg = _("Failed to parse request. Parameter %s not "
"specified") % param
raise webob.exc.HTTPUnprocessableEntity(msg)
res_dict[param['attr']] = param_value
return body
def create_resource(collection, resource, plugin, conf, params):
controller = Controller(plugin, collection, resource, params)
# NOTE(jkoelker) To anyone wishing to add "proper" xml support
# this is where you do it
serializers = {
# 'application/xml': wsgi.XMLDictSerializer(metadata, XML_NS_V20),
}
deserializers = {
# 'application/xml': wsgi.XMLDeserializer(metadata),
}
return wsgi_resource.Resource(controller, FAULT_MAP, deserializers,
serializers)