cinderlib.persistence package

Submodules

cinderlib.persistence.base module

class cinderlib.persistence.base.DB(persistence_driver)

Bases: object

Replacement for DB access methods.

This will serve as replacement for methods used by:

• Drivers
• OVOs’ get_by_id and save methods
• DB implementation

Data will be retrieved using the persistence driver we setup.

get_volume_type(context, id, inactive=False, expected_fields=None)

classmethod image_volume_cache_get_by_volume_id(context, volume_id)

qos_specs_get(context, qos_specs_id, inactive=False)

snapshot_get(context, snapshot_id, *args, **kwargs)

volume_get(context, volume_id, *args, **kwargs)

class cinderlib.persistence.base.PersistenceDriverBase(**kwargs)

Bases: object

Provide Metadata Persistency for our resources.

This class will be used to store new resources as they are created, updated, and removed, as well as provide a mechanism for users to retrieve volumes, snapshots, and connections.

db

delete_connection(connection)

delete_key_value(key)

delete_snapshot(snapshot)

delete_volume(volume)

get_changed_fields(resource)

get_connections(connection_id=None, volume_id=None)

get_fields(resource)

get_key_values(key)

get_snapshots(snapshot_id=None, snapshot_name=None, volume_id=None)

get_volumes(volume_id=None, volume_name=None, backend_name=None)

reset_change_tracker(resource, fields=None)

set_connection(connection)

set_key_value(key_value)

set_snapshot(snapshot)

set_volume(volume)

cinderlib.persistence.dbms module

class cinderlib.persistence.dbms.DBPersistence(connection, sqlite_synchronous=True, soft_deletes=False)

Bases: cinderlib.persistence.base.PersistenceDriverBase

db

delete_connection(connection)

delete_key_value(key_value)

delete_snapshot(snapshot)

delete_volume(volume)

get_connections(connection_id=None, volume_id=None)

get_key_values(key=None)

get_snapshots(snapshot_id=None, snapshot_name=None, volume_id=None)

get_volumes(volume_id=None, volume_name=None, backend_name=None)

set_connection(connection)

set_key_value(key_value)

set_snapshot(snapshot)

set_volume(volume)

class cinderlib.persistence.dbms.MemoryDBPersistence

Bases: cinderlib.persistence.dbms.DBPersistence

cinderlib.persistence.memory module

class cinderlib.persistence.memory.MemoryPersistence

Bases: cinderlib.persistence.base.PersistenceDriverBase

connections = {}

db

delete_connection(connection)

delete_key_value(key_value)

delete_snapshot(snapshot)

delete_volume(volume)

get_connections(connection_id=None, volume_id=None)

get_key_values(key=None)

get_snapshots(snapshot_id=None, snapshot_name=None, volume_id=None)

get_volumes(volume_id=None, volume_name=None, backend_name=None)

key_values = {}

set_connection(connection)

set_key_value(key_value)

set_snapshot(snapshot)

set_volume(volume)

snapshots = {}

volumes = {}

Module contents

class cinderlib.persistence.MyDict

Bases: dict

Custom non clearable dictionary.

Required to overcome the nature of oslo.config where configuration comes from files and command line input.

Using this dictionary we can load from memory everything and it won’t clear things when we dynamically load a driver and the driver has new configuration options.

clear()

cinderlib.persistence.setup(config)

Setup persistence to be used in cinderlib.

By default memory persistance will be used, but there are other mechanisms available and other ways to use custom mechanisms:

• Persistence plugins: Plugin mechanism uses Python entrypoints under namespace cinderlib.persistence.storage, and cinderlib comes with 3 different mechanisms, “memory”, “dbms”, and “memory_dbms”. To use any of these one must pass the string name in the storage parameter and any other configuration as keyword arguments.
• Passing a class that inherits from PersistenceDriverBase as storage parameter and initialization parameters as keyword arguments.
• Passing an instance that inherits from PersistenceDriverBase as storage parameter.