e7b40242f8
This is the start of an effort to both validate that drivers fully implement the expected minimum requirements as well as to create a clear place for driver developers to learn what needs to be implemented and get documentation explaining what is expected for each method. This also enables us to create tooling for documenting the available drivers and their capabilities, to some degree. A follow up patch will show some of what I'm thinking there, but it will make it possible to write scripts for different needs. This is somewhat a cleanup attempt to the ABC work that was started a while back. This does not aim to replace that effort, but give a mechanism for some of the things expected out of that effort that ended up not being possible with how it evolved. In most cases we do not really care if a driver is inherited from a certain base class, just that it conforms to the given interface. The interface/inheritance work really centers around two separate things: * Ensuring drivers conform to an expected interface * Allowing code reuse and common implementation This is really for the first item. Additional work is needed to complete the ABC work we've done, but that really focuses on the second item, and is out of scope for the intent of this patch. Change-Id: I4168225126fe88c31712d94f0a130e9e7ede3446
112 lines
3.9 KiB
Python
112 lines
3.9 KiB
Python
# Copyright 2016 Dell Inc.
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# All Rights Reserved.
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#
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# Licensed under the Apache License, Version 2.0 (the "License"); you may
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# not use this file except in compliance with the License. You may obtain
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# a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
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# License for the specific language governing permissions and limitations
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# under the License.
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#
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"""
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Core backup driver interface.
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All backup drivers should support this interface as a bare minimum.
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"""
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from cinder.interface import base
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class BackupDriver(base.CinderInterface):
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"""Backup driver required interface."""
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def get_metadata(self, volume_id):
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"""Get volume metadata.
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Returns a json-encoded dict containing all metadata and the restore
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version i.e. the version used to decide what actually gets restored
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from this container when doing a backup restore.
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Typically best to use py:class:`BackupMetadataAPI` for this.
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:param volume_id: The ID of the volume.
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:returns: json-encoded dict of metadata.
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"""
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def put_metadata(self, volume_id, json_metadata):
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"""Set volume metadata.
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Typically best to use py:class:`BackupMetadataAPI` for this.
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:param volume_id: The ID of the volume.
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:param json_metadata: The json-encoded dict of metadata.
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"""
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def backup(self, backup, volume_file, backup_metadata=False):
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"""Start a backup of a specified volume.
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If backup['parent_id'] is given, then an incremental backup
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should be performed is supported.
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If the parent backup is a different size, a full backup should be
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performed to ensure all data is included.
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TODO(smcginnis) Document backup variable structure.
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:param backup: The backup information.
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:param volume_file: The volume or file to write the backup to.
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:param backup_metadata: Whether to include volume metadata in the
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backup.
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"""
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def restore(self, backup, volume_id, volume_file):
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"""Restore data from a backup.
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:param backup: The backup information.
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:param volume_id: The volume to be restored.
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:param volume_file: The volume or file to read the data from.
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"""
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def delete(self, backup):
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"""Delete a backup from the backup store.
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:param backup: The backup to be deleted.
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"""
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def export_record(self, backup):
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"""Export driver specific backup record information.
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If backup backend needs additional driver specific information to
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import backup record back into the system it must overwrite this method
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and return it here as a dictionary so it can be serialized into a
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string.
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Default backup driver implementation has no extra information.
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:param backup: backup object to export
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:returns: driver_info - dictionary with extra information
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"""
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def import_record(self, backup, driver_info):
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"""Import driver specific backup record information.
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If backup backend needs additional driver specific information to
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import backup record back into the system it must overwrite this method
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since it will be called with the extra information that was provided by
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export_record when exporting the backup.
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Default backup driver implementation does nothing since it didn't
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export any specific data in export_record.
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:param backup: backup object to export
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:param driver_info: dictionary with driver specific backup record
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information
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:returns: nothing
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"""
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