MockStorageClassDelegate

class lsst.pipe.base.tests.mocks.MockStorageClassDelegate(storageClass: StorageClass)

Bases: StorageClassDelegate

Implementation of the StorageClassDelegate interface for mock datasets.

This class does not implement assembly and disassembly just because it’s not needed right now. That could be added in the future with some additional tracking attributes in MockDataset.

Methods Summary

assemble(components[, pytype])	Construct an object from components based on storageClass.
disassemble(composite[, subset, override])	Disassembler a composite.
getComponent(composite, componentName)	Attempt to retrieve component from composite object by heuristic.
handleParameters(inMemoryDataset[, parameters])	Modify the in-memory dataset using the supplied parameters.

Methods Documentation

assemble(components: dict[str, Any], pytype: type | None = None) → MockDataset

Construct an object from components based on storageClass.

This generic implementation assumes that instances of objects can be created either by passing all the components to a constructor or by calling setter methods with the name.

Parameters

componentsdict

Collection of components from which to assemble a new composite object. Keys correspond to composite names in the StorageClass.

pytypetype, optional

Override the type from the StorageClassDelegate.storageClass to use when assembling the final object.

Returns

compositeobject

New composite object assembled from components.

Raises

ValueError

Some components could not be used to create the object or, alternatively, some components were not defined in the associated StorageClass.

disassemble(composite: Any, subset: Iterable | None = None, override: Any | None = None) → dict[str, DatasetComponent]

Disassembler a composite.

This is a generic implementation of a disassembler. This implementation attempts to extract components from the parent by looking for attributes of the same name or getter methods derived from the component name.

Parameters

compositeobject

Parent composite object consisting of components to be extracted.

subsetiterable, optional

Iterable containing subset of components to extract from composite. Must be a subset of those defined in StorageClassDelegate.storageClass.

overrideobject, optional

Object to use for disassembly instead of parent. This can be useful when called from subclasses that have composites in a hierarchy.

Returns

componentsdict

dict with keys matching the components defined in StorageClassDelegate.storageClass and values being DatasetComponent instances describing the component.

Raises

ValueError

A requested component can not be found in the parent using generic lookups.

TypeError

The parent object does not match the supplied StorageClassDelegate.storageClass.

getComponent(composite: Any, componentName: str) → Any

Attempt to retrieve component from composite object by heuristic.

Will attempt a direct attribute retrieval, or else getter methods of the form “get_componentName” and “getComponentName”.

Parameters

compositeobject

Item to query for the component.

componentNamestr

Name of component to retrieve.

Returns

componentobject

Component extracted from composite.

Raises

AttributeError

The attribute could not be read from the composite.

handleParameters(inMemoryDataset: Any, parameters: Mapping[str, Any] | None = None) → Any

Modify the in-memory dataset using the supplied parameters.

Can return a possibly new object.

For safety, if any parameters are given to this method an exception will be raised. This is to protect the user from thinking that parameters have been applied when they have not been applied.

Parameters

inMemoryDatasetobject

Object to modify based on the parameters.

parametersdict

Parameters to apply. Values are specific to the parameter. Supported parameters are defined in the associated StorageClass. If no relevant parameters are specified the inMemoryDataset will be return unchanged.

Returns

inMemoryDatasetobject

Updated form of supplied in-memory dataset, after parameters have been used.

Raises

ValueError

Parameters have been provided to this default implementation.