CollectionManager

class lsst.daf.butler.registry.interfaces.CollectionManager

Bases: abc.ABC

An interface for managing the collections (including runs) in a Registry.

Notes

Each layer in a multi-layer Registry has its own record for any collection for which it has datasets (or quanta). Different layers may use different IDs for the same collection, so any usage of the IDs obtained through the CollectionManager APIs are strictly for internal (to Registry) use.

Methods Summary

addCollectionForeignKey(tableSpec, *, …)	Add a foreign key (field and constraint) referencing the collection table.
addRunForeignKey(tableSpec, *, prefix, …)	Add a foreign key (field and constraint) referencing the run table.
find(name)	Return the collection record associated with the given name.
getCollectionForeignKeyName(prefix)	Return the name of the field added by addCollectionForeignKey if called with the same prefix.
getRunForeignKeyName(prefix)	Return the name of the field added by addRunForeignKey if called with the same prefix.
initialize(db, context)	Construct an instance of the manager.
refresh()	Ensure all other operations on this manager are aware of any collections that may have been registered by other clients since it was initialized or last refreshed.
register(name, type)	Ensure that a collection of the given name and type are present in the layer this manager is associated with.
remove(name)	Completely remove a collection.

Methods Documentation

classmethod addCollectionForeignKey(tableSpec: lsst.daf.butler.core.ddl.TableSpec, *, prefix: str = 'collection', onDelete: Optional[str] = None, **kwds) → lsst.daf.butler.core.ddl.FieldSpec

Add a foreign key (field and constraint) referencing the collection table.

Parameters:

tableSpec : ddl.TableSpec

Specification for the table that should reference the collection table. Will be modified in place.

prefix: `str`, optional

A name to use for the prefix of the new field; the full name may have a suffix (and is given in the returned ddl.FieldSpec).

onDelete: `str`, optional

One of “CASCADE” or “SET NULL”, indicating what should happen to the referencing row if the collection row is deleted. None indicates that this should be an integrity error.

**kwds

Additional keyword arguments are forwarded to the ddl.FieldSpec constructor (only the name and dtype arguments are otherwise provided).

Returns:

fieldSpec : ddl.FieldSpec

Specification for the field being added.

classmethod addRunForeignKey(tableSpec: lsst.daf.butler.core.ddl.TableSpec, *, prefix: str = 'run', onDelete: Optional[str] = None, **kwds) → lsst.daf.butler.core.ddl.FieldSpec

Add a foreign key (field and constraint) referencing the run table.

Parameters:

tableSpec : ddl.TableSpec

Specification for the table that should reference the run table. Will be modified in place.

prefix: `str`, optional

A name to use for the prefix of the new field; the full name may have a suffix (and is given in the returned ddl.FieldSpec).

onDelete: `str`, optional

One of “CASCADE” or “SET NULL”, indicating what should happen to the referencing row if the collection row is deleted. None indicates that this should be an integrity error.

**kwds

Additional keyword arguments are forwarded to the ddl.FieldSpec constructor (only the name and dtype arguments are otherwise provided).

Returns:

fieldSpec : ddl.FieldSpec

Specification for the field being added.

find(name: str) → lsst.daf.butler.registry.interfaces._collections.CollectionRecord

Return the collection record associated with the given name.

Parameters:

name : str

Name of the collection.

Returns:

record : CollectionRecord

Object representing the collection, including its type and ID. If record.type is CollectionType.RUN, this will be a RunRecord instance. If record.type is CollectionType.CHAIN, this will be a ChainedCollectionRecord instance.

Raises:

MissingCollectionError

Raised if the given collection does not exist.

Notes

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

classmethod getCollectionForeignKeyName(prefix: str = 'collection') → str

Return the name of the field added by addCollectionForeignKey if called with the same prefix.

Parameters:

prefix : str

A name to use for the prefix of the new field; the full name may have a suffix.

Returns:

name : str

The field name.

classmethod getRunForeignKeyName(prefix: str = 'run') → str

Return the name of the field added by addRunForeignKey if called with the same prefix.

Parameters:

prefix : str

A name to use for the prefix of the new field; the full name may have a suffix.

Returns:

name : str

The field name.

classmethod initialize(db: Database, context: StaticTablesContext) → CollectionManager

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.

Returns:

manager : CollectionManager

An instance of a concrete CollectionManager subclass.

refresh() → None

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

register(name: str, type: lsst.daf.butler.registry._collectionType.CollectionType) → lsst.daf.butler.registry.interfaces._collections.CollectionRecord

Ensure that a collection of the given name and type are present in the layer this manager is associated with.

Parameters:

name : str

Name of the collection.

type : CollectionType

Enumeration value indicating the type of collection.

Returns:

record : CollectionRecord

Object representing the collection, including its type and ID. If type is CollectionType.RUN, this will be a RunRecord instance. If type is CollectionType.CHAIN, this will be a ChainedCollectionRecord instance.

Raises:

TransactionInterruption

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

DatabaseConflictError

Raised if a collection with this name but a different type already exists.

Notes

Concurrent registrations of the same collection should be safe; nothing should happen if the types are consistent, and integrity errors due to inconsistent types should happen before any database changes are made.

remove(name: str) → None

Completely remove a collection.

Any existing CollectionRecord objects that correspond to the removed collection are considered invalidated.

Parameters:

name : str

Name of the collection to remove.

Notes

If this collection is referenced by foreign keys in tables managed by other objects, the ON DELETE clauses of those tables will be invoked. That will frequently delete many dependent rows automatically (via “CASCADE”, but it may also cause this operation to fail (with rollback) unless dependent rows that do not have an ON DELETE clause are removed first.