lenskit.pipeline.ComponentInputHook
===================================

.. py:class:: lenskit.pipeline.ComponentInputHook
   :canonical: lenskit.pipeline._hooks.ComponentInputHook

   Bases: :py:obj:`Protocol`


   Inspect or process data as it passes to a component's input.

   As with all :ref:`pipeline-hooks`, an input hook is a callable that is run
   at the appropriate stage of the input.

   Component input hooks are installed under the name ``component-input``.

   :Stability: Experimental


   .. py:method:: __call__(node, input, value, **context)

      Inspect or process the component input data.

      :param node: The component node being invoked.
      :param input_name: The name of the component's input that will receive the data.
      :param input_type: The type of data the component expects for this input, if one
                         was specified in the component definition.
      :param value: The data value to be supplied.  This is declared
                    :class:`object`, because its type is not known or guaranteed in
                    the genral case.
      :param context: Additional context variables, mostly for the use of internal hooks.

      :returns: The value to pass to the component.  For inspection-only hooks, this
                will just be ``value``; hooks can also substitute alternative
                values depending on application needs.