# -*- coding: utf-8 -*-
#
# Copyright © 2013 Unitedstack 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.
"""A middleware that turns exceptions into parsable string.
Inspired by Cinder's faultwrapper.
"""
import sys
import traceback
from oslo_config import cfg
from oslo_utils import reflection
import webob
from heat.common import exception
from heat.common import serializers
from heat.common import wsgi
[docs]
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 = serializers.XMLResponseSerializer()
else:
serializer = serializers.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
[docs]
class FaultWrapper(wsgi.Middleware):
"""Replace error body with something the client can parse."""
error_map = {
'AttributeError': webob.exc.HTTPBadRequest,
'ActionInProgress': webob.exc.HTTPConflict,
'ValueError': webob.exc.HTTPBadRequest,
'EntityNotFound': webob.exc.HTTPNotFound,
'NotFound': webob.exc.HTTPNotFound,
'ResourceActionNotSupported': webob.exc.HTTPBadRequest,
'InvalidGlobalResource': webob.exc.HTTPInternalServerError,
'ResourceNotAvailable': webob.exc.HTTPNotFound,
'PhysicalResourceNameAmbiguity': webob.exc.HTTPBadRequest,
'PhysicalResourceIDAmbiguity': webob.exc.HTTPBadRequest,
'InvalidTenant': webob.exc.HTTPForbidden,
'Forbidden': webob.exc.HTTPForbidden,
'StackExists': webob.exc.HTTPConflict,
'StackValidationFailed': webob.exc.HTTPBadRequest,
'InvalidSchemaError': webob.exc.HTTPBadRequest,
'InvalidTemplateReference': webob.exc.HTTPBadRequest,
'InvalidTemplateVersion': webob.exc.HTTPBadRequest,
'InvalidTemplateSection': webob.exc.HTTPBadRequest,
'UnknownUserParameter': webob.exc.HTTPBadRequest,
'RevertFailed': webob.exc.HTTPInternalServerError,
'StopActionFailed': webob.exc.HTTPInternalServerError,
'EventSendFailed': webob.exc.HTTPInternalServerError,
'ServerBuildFailed': webob.exc.HTTPInternalServerError,
'InvalidEncryptionKey': webob.exc.HTTPInternalServerError,
'NotSupported': webob.exc.HTTPBadRequest,
'MissingCredentialError': webob.exc.HTTPBadRequest,
'UserParameterMissing': webob.exc.HTTPBadRequest,
'RequestLimitExceeded': webob.exc.HTTPBadRequest,
'DownloadLimitExceeded': webob.exc.HTTPBadRequest,
'Invalid': webob.exc.HTTPBadRequest,
'ResourcePropertyConflict': webob.exc.HTTPBadRequest,
'PropertyUnspecifiedError': webob.exc.HTTPBadRequest,
'ObjectFieldInvalid': webob.exc.HTTPBadRequest,
'ReadOnlyFieldError': webob.exc.HTTPBadRequest,
'ObjectActionError': webob.exc.HTTPBadRequest,
'IncompatibleObjectVersion': webob.exc.HTTPBadRequest,
'OrphanedObjectError': webob.exc.HTTPBadRequest,
'UnsupportedObjectError': webob.exc.HTTPBadRequest,
'ResourceTypeUnavailable': webob.exc.HTTPBadRequest,
'InvalidBreakPointHook': webob.exc.HTTPBadRequest,
'ImmutableParameterModified': webob.exc.HTTPBadRequest,
'CircularDependencyException': webob.exc.HTTPBadRequest
}
def _map_exception_to_error(self, class_exception):
if class_exception == Exception:
return webob.exc.HTTPInternalServerError
if class_exception.__name__ not in self.error_map:
return self._map_exception_to_error(class_exception.__base__)
return self.error_map[class_exception.__name__]
def _error(self, ex):
trace = None
traceback_marker = 'Traceback (most recent call last)'
webob_exc = None
safe = getattr(ex, 'safe', False)
if isinstance(ex, exception.HTTPExceptionDisguise):
# An HTTP exception was disguised so it could make it here
# let's remove the disguise and set the original HTTP exception
if cfg.CONF.debug:
trace = ''.join(traceback.format_tb(ex.tb))
ex = ex.exc
webob_exc = ex
ex_type = reflection.get_class_name(ex, fully_qualified=False)
is_remote = ex_type.endswith('_Remote')
if is_remote:
ex_type = ex_type[:-len('_Remote')]
full_message = str(ex)
if '\n' in full_message and is_remote:
message, msg_trace = full_message.split('\n', 1)
elif traceback_marker in full_message:
message, msg_trace = full_message.split(traceback_marker, 1)
message = message.rstrip('\n')
msg_trace = traceback_marker + msg_trace
else:
msg_trace = 'None\n'
if sys.exc_info() != (None, None, None):
msg_trace = traceback.format_exc()
message = full_message
if isinstance(ex, exception.HeatException):
message = ex.message
if cfg.CONF.debug and not trace:
trace = msg_trace
if not webob_exc:
webob_exc = self._map_exception_to_error(ex.__class__)
error = {
'code': webob_exc.code,
'title': webob_exc.title,
'explanation': webob_exc.explanation,
'error': {
'type': ex_type,
'traceback': trace,
}
}
if safe:
error['error']['message'] = message
return error
[docs]
def process_request(self, req):
try:
return req.get_response(self.application)
except Exception as exc:
return req.get_response(Fault(self._error(exc)))
