MetadataRouter#

class sklearn.utils.metadata_routing.MetadataRouter(owner)[source]#

Stores and handles metadata routing for a router object.

This class is used by router objects to store and handle metadata routing. Routing information is stored as a dictionary of the form {"object_name": RouteMappingPair(method_mapping, routing_info)}, where method_mapping is an instance of MethodMapping and routing_info is either a MetadataRequest or a MetadataRouter instance.

Added in version 1.3.

Parameters:

ownerstr: The name of the object to which these requests belong.

add(*, method_mapping, **objs)[source]#

Add named objects with their corresponding method mapping.

Parameters:

method_mappingMethodMapping: The mapping between the child and the parent’s methods.
**objsdict: A dictionary of objects from which metadata is extracted by calling get_routing_for_object on them.

Returns:

selfMetadataRouter: Returns self.

add_self_request(obj)[source]#

Add self (as a consumer) to the routing.

This method is used if the router is also a consumer, and hence the router itself needs to be included in the routing. The passed object can be an estimator or a MetadataRequest.

A router should add itself using this method instead of add since it should be treated differently than the other objects to which metadata is routed by the router.

Parameters:

objobject: This is typically the router instance, i.e. self in a get_metadata_routing() implementation. It can also be a MetadataRequest instance.

Returns:

selfMetadataRouter: Returns self.

consumes(method, params)[source]#

Check whether the given parameters are consumed by the given method.

Added in version 1.4.

Parameters:

methodstr: The name of the method to check.
paramsiterable of str: An iterable of parameters to check.

Returns:

consumedset of str: A set of parameters which are consumed by the given method.

route_params(*, caller, params)[source]#

Return the input parameters requested by child objects.

The output of this method is a bunch, which includes the metadata for all methods of each child object that is used in the router’s caller method.

If the router is also a consumer, it also checks for warnings of self’s/consumer’s requested metadata.

Parameters:

callerstr: The name of the method for which the parameters are requested and routed. If called inside the fit method of a router, it would be "fit".
paramsdict: A dictionary of provided metadata.

Returns:

paramsBunch: A Bunch of the form {"object_name": {"method_name": {params: value}}} which can be used to pass the required metadata to corresponding methods or corresponding child objects.

validate_metadata(*, method, params)[source]#

Validate given metadata for a method.

This raises a TypeError if some of the passed metadata are not understood by child objects.

Parameters:

methodstr: The name of the method for which the parameters are requested and routed. If called inside the fit method of a router, it would be "fit".
paramsdict: A dictionary of provided metadata.

Gallery examples#

Metadata Routing