glance_store/glance_store/exceptions.py
Zhi Yan Liu 138875b7c3 Add capabilities to storage driver
Storage capabilities is used to indicate the static and dynamic ability
of the storage driver object based on current driver implementation or
particular driver configuration and backend status.

Use storage capabilities glance_store can do more proper operations on
backend to support upper layer request, like to enable or disable add()
function to glance, or if allow glance reuse driver instance for all
request according to whether the driver and/or backend is stateless.

This patch implemented some initial capabilities for existing drivers,
and change the foundational code to make them be aware. Mainly it
contains:

1. Implemented essential code to enable driver capabilities, adding
necessary capabilities.

2. Added a generic checker on necessary storage operations, to make sure
the capabilities of the driver are capable of handling requested
operation. We can enhance the check logic as needed easily in future.

3. Added a callback based schedule logic to update dynamic capabilities
of store when operator enabled it by a option.

4. Refactoring on existing disablement logic on driver add() interface,
to use consistent capabilities way to handle it, removed add_disabled().

5. Therefor the related exception conversion logic for other interfaces
are redundant, due to now we can raise proper exception directly from
the checker.

6. Added the logic to recreate drive object if the storage and/or driver
isn't stateless.

Few minor changes need to be added to Glance side:
Change Ibbc85b6bc2ea98c564d316db2874d7df5aac32a6 .

docImpact
Implements: blueprint store-capabilities

Change-Id: Iedf0d4f829e46ca64c3f4fc6a7dfee54d9b0605b
Signed-off-by: Zhi Yan Liu <zhiyanl@cn.ibm.com>
2015-02-08 12:41:47 +08:00

215 lines
6.0 KiB
Python

# Copyright (c) 2014 Red Hat, 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.
"""Glance Store exception subclasses"""
import six.moves.urllib.parse as urlparse
from glance_store import i18n
_ = i18n._
class BackendException(Exception):
pass
class UnsupportedBackend(BackendException):
pass
class RedirectException(Exception):
def __init__(self, url):
self.url = urlparse.urlparse(url)
class GlanceStoreException(Exception):
"""
Base Glance Store Exception
To correctly use this class, inherit from it and define
a 'message' property. That message will get printf'd
with the keyword arguments provided to the constructor.
"""
message = ''
def __init__(self, **kwargs):
self.msg = kwargs.pop('message', None) or self.message % kwargs
super(Exception, self).__init__(self.msg)
class MissingCredentialError(GlanceStoreException):
message = _("Missing required credential: %(required)s")
class BadAuthStrategy(GlanceStoreException):
message = _("Incorrect auth strategy, expected \"%(expected)s\" but "
"received \"%(received)s\"")
class AuthorizationRedirect(GlanceStoreException):
message = _("Redirecting to %(uri)s for authorization.")
class NotFound(GlanceStoreException):
message = _("Image %(image)s not found")
class UnknownScheme(GlanceStoreException):
message = _("Unknown scheme '%(scheme)s' found in URI")
class BadStoreUri(GlanceStoreException):
message = _("The Store URI was malformed: %(uri)s")
class Duplicate(GlanceStoreException):
message = _("Image %(image)s already exists")
class Conflict(GlanceStoreException):
message = _("An object with the same identifier is currently being "
"operated on.")
class StorageFull(GlanceStoreException):
message = _("There is not enough disk space on the image storage media.")
class StorageWriteDenied(GlanceStoreException):
message = _("Permission to write image storage media denied.")
class AuthBadRequest(GlanceStoreException):
message = _("Connect error/bad request to Auth service at URL %(url)s.")
class AuthUrlNotFound(GlanceStoreException):
message = _("Auth service at URL %(url)s not found.")
class AuthorizationFailure(GlanceStoreException):
message = _("Authorization failed.")
class NotAuthenticated(GlanceStoreException):
message = _("You are not authenticated.")
class Forbidden(GlanceStoreException):
message = _("You are not authorized to complete this action.")
class ForbiddenPublicImage(Forbidden):
message = _("You are not authorized to complete this action.")
class ProtectedImageDelete(Forbidden):
message = _("Image %(image_id)s is protected and cannot be deleted.")
class Invalid(GlanceStoreException):
message = _("Data supplied was not valid.")
class BadStoreConfiguration(GlanceStoreException):
message = _("Store %(store_name)s could not be configured correctly. "
"Reason: %(reason)s")
class DriverLoadFailure(GlanceStoreException):
message = _("Driver %(driver_name)s could not be loaded.")
class BadDriverConfiguration(GlanceStoreException):
message = _("Driver %(driver_name)s could not be configured correctly. "
"Reason: %(reason)s")
class StoreDeleteNotSupported(GlanceStoreException):
message = _("Deleting images from this store is not supported.")
class StoreGetNotSupported(GlanceStoreException):
message = _("Getting images from this store is not supported.")
class StoreRandomGetNotSupported(StoreGetNotSupported):
message = _("Getting images randomly from this store is not supported. "
"Offset: %(offset)s, length: %(chunk_size)s")
class StoreAddDisabled(GlanceStoreException):
message = _("Configuration for store failed. Adding images to this "
"store is disabled.")
class MaxRedirectsExceeded(GlanceStoreException):
message = _("Maximum redirects (%(redirects)s) was exceeded.")
class InvalidRedirect(GlanceStoreException):
message = _("Received invalid HTTP redirect.")
class NoServiceEndpoint(GlanceStoreException):
message = _("Response from Keystone does not contain a Glance endpoint.")
class RegionAmbiguity(GlanceStoreException):
message = _("Multiple 'image' service matches for region %(region)s. This "
"generally means that a region is required and you have not "
"supplied one.")
class RemoteServiceUnavailable(GlanceStoreException):
message = _("Remote server where the image is present is unavailable.")
class WorkerCreationFailure(GlanceStoreException):
message = _("Server worker creation failed: %(reason)s.")
class SchemaLoadError(GlanceStoreException):
message = _("Unable to load schema: %(reason)s")
class InvalidObject(GlanceStoreException):
message = _("Provided object does not match schema "
"'%(schema)s': %(reason)s")
class UnsupportedHeaderFeature(GlanceStoreException):
message = _("Provided header feature is unsupported: %(feature)s")
class InUseByStore(GlanceStoreException):
message = _("The image cannot be deleted because it is in use through "
"the backend store outside of Glance.")
class ImageDataNotFound(NotFound):
message = _("No image data could be found")
class InvalidParameterValue(Invalid):
message = _("Invalid value '%(value)s' for parameter '%(param)s': "
"%(extra_msg)s")
class InvalidImageStatusTransition(Invalid):
message = _("Image status transition from %(cur_status)s to"
" %(new_status)s is not allowed")