DimensionRecordStorageManager

class lsst.daf.butler.registry.interfaces.DimensionRecordStorageManager(*, universe: DimensionUniverse)

Bases: abc.ABC

An interface for managing the dimension records in a Registry.

DimensionRecordStorageManager primarily serves as a container and factory for DimensionRecordStorage instances, which each provide access to the records for a different DimensionElement.

Parameters:

universe : DimensionUniverse

Universe of all dimensions and dimension elements known to the Registry.

Notes

In a multi-layer Registry, many dimension elements will only have records in one layer (often the base layer). The union of the records across all layers forms the logical table for the full Registry.

Methods Summary

clearCaches()	Clear any in-memory caches held by nested DimensionRecordStorage instances.
get(element)	Return an object that provides access to the records associated with the given element, if one exists in this layer.
initialize(db, context, *, universe)	Construct an instance of the manager.
refresh()	Ensure all other operations on this manager are aware of any dataset types that may have been registered by other clients since it was initialized or last refreshed.
register(element)	Ensure that this layer can hold records for the given element, creating new tables as necessary.

Methods Documentation

clearCaches()

Clear any in-memory caches held by nested DimensionRecordStorage instances.

This is called by Registry when transactions are rolled back, to avoid in-memory caches from ever containing records that are not present in persistent storage.

get(element: DimensionElement) → Optional[DimensionRecordStorage]

Return an object that provides access to the records associated with the given element, if one exists in this layer.

Parameters:

element : DimensionElement

Element for which records should be returned.

Returns:

records : DimensionRecordStorage or None

The object representing the records for the given element in this layer, or None if there are no records for that element in this layer.

Notes

Dimension elements registered by another client of the same layer since the last call to initialize or refresh may not be found.

classmethod initialize(db: Database, context: StaticTablesContext, *, universe: DimensionUniverse) → DimensionRecordStorageManager

Construct an instance of the manager.

Parameters:

db : Database

Interface to the underlying database engine and namespace.

context : StaticTablesContext

Context object obtained from Database.declareStaticTables; used to declare any tables that should always be present in a layer implemented with this manager.

universe : DimensionUniverse

Universe graph containing dimensions known to this Registry.

Returns:

manager : DimensionRecordStorageManager

An instance of a concrete DimensionRecordStorageManager subclass.

refresh()

Ensure all other operations on this manager are aware of any dataset types that may have been registered by other clients since it was initialized or last refreshed.

register(element: DimensionElement) → DimensionRecordStorage

Ensure that this layer can hold records for the given element, creating new tables as necessary.

Parameters:

element : DimensionElement

Element for which a table should created (as necessary) and an associated DimensionRecordStorage returned.

Returns:

records : DimensionRecordStorage

The object representing the records for the given element in this layer.

Raises:

TransactionInterruption

Raised if this operation is invoked within a Database.transaction context.