# Copyright 2014, Rackspace, US, Inc.
#
# 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 functools
import json
import logging
from django.conf import settings
from django import http
from django.utils import decorators
from oslo_serialization import jsonutils
from horizon import exceptions
log = logging.getLogger(__name__)
[docs]class AjaxError(Exception):
def __init__(self, http_status, msg):
self.http_status = http_status
super(AjaxError, self).__init__(msg)
http_errors = exceptions.UNAUTHORIZED + exceptions.NOT_FOUND + \
exceptions.RECOVERABLE + (AjaxError, )
[docs]class CreatedResponse(http.HttpResponse):
def __init__(self, location, data=None):
if data is not None:
content = jsonutils.dumps(data, sort_keys=settings.DEBUG)
content_type = 'application/json'
else:
content = ''
content_type = None
super(CreatedResponse, self).__init__(status=201, content=content,
content_type=content_type)
self['Location'] = location
[docs]class JSONResponse(http.HttpResponse):
def __init__(self, data, status=200):
if status == 204:
content = ''
else:
content = jsonutils.dumps(data, sort_keys=settings.DEBUG)
super(JSONResponse, self).__init__(
status=status,
content=content,
content_type='application/json',
)
[docs]def ajax(authenticated=True, data_required=False):
'''Provide a decorator to wrap a view method so that it may exist in an
entirely AJAX environment:
- data decoded from JSON as input and data coded as JSON as output
- result status is coded in the HTTP status code; any non-2xx response
data will be coded as a JSON string, otherwise the response type (always
JSON) is specific to the method called.
if authenticated is true then we'll make sure the current user is
authenticated.
If data_required is true then we'll assert that there is a JSON body
present.
The wrapped view method should return either:
- JSON serialisable data
- an object of the django http.HttpResponse subclass (one of JSONResponse
or CreatedResponse is suggested)
- nothing
Methods returning nothing (or None explicitly) will result in a 204 "NO
CONTENT" being returned to the caller.
'''
def decorator(function, authenticated=authenticated,
data_required=data_required):
@functools.wraps(function,
assigned=decorators.available_attrs(function))
def _wrapped(self, request, *args, **kw):
if authenticated and not request.user.is_authenticated():
return JSONResponse('not logged in', 401)
if not request.is_ajax():
return JSONResponse('request must be AJAX', 400)
# decode the JSON body if present
request.DATA = None
if request.body:
try:
request.DATA = json.loads(request.body)
except (TypeError, ValueError) as e:
return JSONResponse('malformed JSON request: %s' % e, 400)
if data_required:
if not request.DATA:
return JSONResponse('request requires JSON body', 400)
# invoke the wrapped function, handling exceptions sanely
try:
data = function(self, request, *args, **kw)
if isinstance(data, http.HttpResponse):
return data
elif data is None:
return JSONResponse('', status=204)
return JSONResponse(data)
except http_errors as e:
# exception was raised with a specific HTTP status
if hasattr(e, 'http_status'):
http_status = e.http_status
else:
http_status = e.code
return JSONResponse(str(e), http_status)
except Exception as e:
log.exception('error invoking apiclient')
return JSONResponse(str(e), 500)
return _wrapped
return decorator