Class HaystackAction

burr/integrations/haystack.py:32–288

Burr ``Action`` wrapping a Haystack ``Component``. Haystack ``Component`` is the basic block of a Haystack ``Pipeline``. A ``Component`` is instantiated, then it receives inputs for its ``.run()`` method and returns output values. Learn more about components here: https://docs.hays

# TODO show OpenTelemetry integration
class HaystackAction(Action):
    """Burr ``Action`` wrapping a Haystack ``Component``.

    Haystack ``Component`` is the basic block of a Haystack ``Pipeline``.
    A ``Component`` is instantiated, then it receives inputs for its ``.run()`` method
    and returns output values.

    Learn more about components here: https://docs.haystack.deepset.ai/docs/custom-components
    """

    def __init__(
        self,
        component: Component,
        reads: Union[list[str], dict[str, str]],
        writes: Union[list[str], dict[str, str]],
        name: Optional[str] = None,
        bound_params: Optional[dict] = None,
        do_warm_up: bool = True,
    ):
        """Create a Burr ``Action`` from a Haystack ``Component``.

        :param component: Haystack ``Component`` to wrap
        :param reads: State fields read and passed to ``Component.run()``.
        Use a mapping {socket: state_field} to rename Haystack input sockets (see example).
        :param writes: State fields where results of ``Component.run()`` are written.
        Use a mapping {state_field: socket} to rename Haystack output sockets (see example).
        :param name: Name of the action. Can be set later via ``.with_name()``
        or in ``ApplicationBuilder.with_actions()``.
        :param bound_params: Parameters to bind to the ``Component.run()`` method.
        :param do_warm_up: If True, try to call ``Component.warm_up()`` if it exists.
        If False, we assume ``.warm_up()`` was called before creating the ``HaystackAction``.
        Read more about ``.warm_up()`` in the Haystack documentation: https://docs.haystack.deepset.ai/reference/pipeline-api#pipelinewarm_up

        Pass the mapping ``{"foo": "state_field"}`` to read the value of ``state_field`` on the Burr state
        and pass it to ``Component.run()`` as ``foo``.

            .. code-block:: python

                @component
                class HaystackComponent:
                    @component.output_types()
                    def run(self, foo: int) -> dict:
                        return {}

                HaystackAction(
                    component=HaystackComponent(),
                    reads={"foo": "state_field"},
                    writes=[]
                )

        Pass the mapping ``{"state_field": "bar"}`` to get the ``bar`` value from the results
        of ``.run()`` and set the field ``state_field`` on the Burr state

            .. code-block:: python

                @component
                class HaystackComponent:
                    @component.output_types(bar=int)