heat/heat/api/middleware/fault.py

109 lines
3.5 KiB
Python

# -*- encoding: utf-8 -*-
#
# Copyright © 2013 Unitedstack Inc.
#
# Author: Jianing YANG (jianingy@unitedstack.com)
#
# 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 middleware that turns exceptions into parsable string. Inspired by
Cinder's faultwrapper
"""
import traceback
import webob
from heat.openstack.common import log as logging
import heat.openstack.common.rpc.common as rpc_common
from heat.common import wsgi
logger = logging.getLogger(__name__)
class Fault(object):
def __init__(self, error):
self.error = error
@webob.dec.wsgify(RequestClass=wsgi.Request)
def __call__(self, req):
if req.content_type == 'application/xml':
serializer = wsgi.XMLResponseSerializer()
else:
serializer = wsgi.JSONResponseSerializer()
resp = webob.Response(request=req)
default_webob_exc = webob.exc.HTTPInternalServerError()
resp.status_code = self.error.get('code', default_webob_exc.code)
serializer.default(resp, self.error)
return resp
class FaultWrapper(wsgi.Middleware):
"""Replace error body with something the client can parse."""
error_map = {
'AttributeError': webob.exc.HTTPBadRequest,
'ValueError': webob.exc.HTTPBadRequest,
'StackNotFound': webob.exc.HTTPNotFound,
'ResourceNotFound': webob.exc.HTTPNotFound,
'ResourceNotAvailable': webob.exc.HTTPNotFound,
'PhysicalResourceNotFound': webob.exc.HTTPNotFound,
'InvalidTenant': webob.exc.HTTPForbidden,
'StackExists': webob.exc.HTTPConflict,
'StackValidationFailed': webob.exc.HTTPBadRequest,
'InvalidTemplateReference': webob.exc.HTTPBadRequest,
'UnknownUserParameter': webob.exc.HTTPBadRequest,
'RevertFailed': webob.exc.HTTPInternalServerError,
'ServerBuildFailed': webob.exc.HTTPInternalServerError,
'NotSupported': webob.exc.HTTPBadRequest,
'MissingCredentialError': webob.exc.HTTPBadRequest,
'UserParameterMissing': webob.exc.HTTPBadRequest,
}
def _error(self, ex):
ex_type = ex.__class__.__name__
if ex_type.endswith(rpc_common._REMOTE_POSTFIX):
ex_type = ex_type[:-len(rpc_common._REMOTE_POSTFIX)]
message = str(ex)
if message.find('\n') > -1:
message, trace = message.split('\n', 1)
else:
message = str(ex)
trace = traceback.format_exc()
webob_exc = self.error_map.get(ex_type,
webob.exc.HTTPInternalServerError)
error = {
'code': webob_exc.code,
'title': webob_exc.title,
'explanation': webob_exc.explanation,
'error': {
'message': message,
'type': ex_type,
'traceback': trace,
}
}
return error
def process_request(self, req):
try:
return req.get_response(self.application)
except Exception as exc:
return req.get_response(Fault(self._error(exc)))