ChainedCollectionRecord

class lsst.daf.butler.registry.interfaces.ChainedCollectionRecord(key: Any, name: str, universe: lsst.daf.butler.core.dimensions._universe.DimensionUniverse)

Bases: lsst.daf.butler.registry.interfaces.CollectionRecord

A subclass of CollectionRecord that adds the list of child collections in a CHAINED collection.

Parameters:

key

Unique collection ID, can be the same as name if name is used for identification. Usually this is an integer or string, but can be other database-specific type.

name : str

Name of the collection.

Attributes Summary

children

The ordered search path of child collections that define this chain (tuple [ str ]).

Methods Summary

refresh(manager)	Load children from the database, using the given manager to resolve collection primary key values into records.
update(manager, children, flatten)	Redefine this chain to search the given child collections.

Attributes Documentation

children

The ordered search path of child collections that define this chain (tuple [ str ]).

Methods Documentation

refresh(manager: lsst.daf.butler.registry.interfaces._collections.CollectionManager) → None

Load children from the database, using the given manager to resolve collection primary key values into records.

This method exists to ensure that all collections that may appear in a chain are known to the manager before any particular chain tries to retrieve their records from it. ChainedCollectionRecord subclasses can rely on it being called sometime after their own __init__ to finish construction.

Parameters:

manager : CollectionManager

The object that manages this records instance and all records instances that may appear as its children.

update(manager: lsst.daf.butler.registry.interfaces._collections.CollectionManager, children: tuple, flatten: bool) → None

Redefine this chain to search the given child collections.

This method should be used by all external code to set children. It delegates to _update, which is what should be overridden by subclasses.

Parameters:

manager : CollectionManager

The object that manages this records instance and all records instances that may appear as its children.

children : tuple [ str ]

A collection search path that should be resolved to set the child collections of this chain.

flatten : bool

If True, recursively flatten out any nested CHAINED collections in children first.

Raises:

ValueError

Raised when the child collections contain a cycle.