Skip to content

hololinked.core.actions.action

action(input_schema: JSON | BaseModel | RootModel | None = None, output_schema: JSON | BaseModel | RootModel | None = None, state: str | Enum | None = None, **kwargs) -> Action

Decorate on your methods to make them accessible remotely or create 'actions' out of them. When used with hardware, actions generally command the hardware to do something.

Parameters:

Name Type Description Default

input_schema

JSON | BaseModel | RootModel | None

schema for arguments to validate

None

output_schema

JSON | BaseModel | RootModel | None

schema for return value, currently only used to inform clients which are supposed to validate on their own

None

state

str | Enum | None

state machine state under which the action can be executed. When not provided, the action can be executed under any state.

None

**kwargs

additional keyword arguments to specify action characteristics:

  • synchronous: bool, indicate in thing description if action is synchronous (not long running/threaded or async) - completes in a deterministic (& usually) short period of time, default True
  • threaded: bool, indicate that a method/action should be run in a separate thread, default False. Alternative to synchronous for non-async methods.
  • create_task: bool, indicate that a method/action should be run in a new task, default True. Alternative to synchronous for async methods.
  • safe: bool, indicate in thing description if action is safe to execute, default False
  • idempotent: bool, indicate in thing description if action is idempotent (for example, allows HTTP clients to cache return value), default False
{}

Returns:

Type Description
Action

returns the callable object wrapped in an Action object. When accessed at instance level, a BoundSyncAction or BoundAsyncAction object is returned.

Source code in hololinked/hololinked/core/actions.py
def action(
    input_schema: JSON | BaseModel | RootModel | None = None,
    output_schema: JSON | BaseModel | RootModel | None = None,
    state: str | Enum | None = None,
    **kwargs,
) -> Action:
    """
    Decorate on your methods to make them accessible remotely or create 'actions' out of them. When used with hardware,
    actions generally command the hardware to do something.

    Parameters
    ----------
    input_schema: JSON | BaseModel | RootModel, optional
        schema for arguments to validate
    output_schema: JSON | BaseModel | RootModel, optional
        schema for return value, currently only used to inform clients which are supposed to validate on their own
    state: str | Tuple[str], optional
        state machine state under which the action can be executed. When not provided, the action can be executed
        under any state.
    **kwargs:
        additional keyword arguments to specify action characteristics:

        - `synchronous`: bool,
            indicate in thing description if action is synchronous (not long running/threaded or async) - completes
            in a deterministic (& usually) short period of time, default `True`
        - `threaded`: bool,
            indicate that a method/action should be run in a separate thread, default `False`.
            Alternative to `synchronous` for non-async methods.
        - `create_task`: bool,
            indicate that a method/action should be run in a new task, default `True`.
            Alternative to `synchronous` for async methods.
        - `safe`: bool,
            indicate in thing description if action is safe to execute, default `False`
        - `idempotent`: bool,
            indicate in thing description if action is idempotent (for example, allows HTTP clients to cache return value),
            default `False`

    Returns
    -------
    Action
        returns the callable object wrapped in an `Action` object. When accessed at instance level,
        a `BoundSyncAction` or `BoundAsyncAction` object is returned.
    """

    def inner(obj):
        input_schema = inner._arguments.get("input_schema", None)
        output_schema = inner._arguments.get("output_schema", None)
        state = inner._arguments.get("state", None)
        kwargs = inner._arguments.get("kwargs", {})

        original = obj
        if (
            not isinstance(obj, (FunctionType, MethodType, Action, BoundAction))
            and not isclassmethod(obj)
            and not issubklass(obj, ParameterizedFunction)
        ):
            raise TypeError(f"target for action or is not a function/method. Given type {type(obj)}") from None
        if isclassmethod(obj):
            obj = obj.__func__
        if isinstance(obj, (Action, BoundAction)):
            if obj.execution_info.isclassmethod:
                raise RuntimeError("cannot wrap a classmethod as action once again, please skip")
            warnings.warn(
                f"{obj.name} is already wrapped as an action, wrapping it again with newer settings.",
                category=UserWarning,
            )
            obj = obj.obj
        if obj.__name__.startswith("__"):
            raise ValueError(f"dunder objects cannot become remote : {obj.__name__}")
        execution_info_validator = ActionInfoValidator()
        if state is not None:
            if isinstance(state, (Enum, str)):
                execution_info_validator.state = (state,)
            else:
                execution_info_validator.state = state
        if "request" in getfullargspec(obj).kwonlyargs:
            execution_info_validator.request_as_argument = True
        execution_info_validator.isaction = True
        execution_info_validator.obj = original
        execution_info_validator.create_task = kwargs.get("create_task", False)
        execution_info_validator.safe = kwargs.get("safe", False)
        execution_info_validator.idempotent = kwargs.get("idempotent", False)
        execution_info_validator.synchronous = kwargs.get("synchronous", True)

        if isclassmethod(original):
            execution_info_validator.iscoroutine = has_async_def(obj)
            execution_info_validator.isclassmethod = True
        elif issubklass(obj, ParameterizedFunction):
            execution_info_validator.iscoroutine = iscoroutinefunction(obj.__call__)
            execution_info_validator.isparameterized = True
        else:
            execution_info_validator.iscoroutine = iscoroutinefunction(obj)

        if not input_schema:
            try:
                input_schema = get_input_model_from_signature(obj, remove_first_positional_arg=True)
            except Exception as ex:
                warnings.warn(
                    f"Could not infer input schema for {obj.__name__} due to - {str(ex)}. "
                    + "Considering filing a bug report if you think this should have worked correctly",
                    category=RuntimeWarning,
                )
        if input_schema:
            if isinstance(input_schema, dict):
                execution_info_validator.schema_validator = JSONSchemaValidator(input_schema)
            elif issubklass(input_schema, (BaseModel, RootModel)):
                execution_info_validator.schema_validator = PydanticSchemaValidator(input_schema)
            else:
                raise TypeError(
                    "input schema must be a JSON schema or a Pydantic model, got {}".format(type(input_schema))
                )
        execution_info_validator.argument_schema = input_schema

        if not output_schema:
            try:
                output_schema = get_return_type_from_signature(obj)
            except Exception as ex:
                warnings.warn(
                    f"Could not infer output schema for {obj.__name__} due to {str(ex)}. "
                    + "Considering filing a bug report if you think this should have worked correctly",
                    category=RuntimeWarning,
                )

        if output_schema:
            # output is not validated by us, so we just check the schema and dont create a validator
            if isinstance(output_schema, dict):
                jsonschema.Draft7Validator.check_schema(output_schema)
                execution_info_validator.return_value_schema = output_schema
            elif issubklass(output_schema, (BaseModel, RootModel)):
                execution_info_validator.return_value_schema = output_schema
            else:
                raise TypeError(
                    "output schema must be a JSON schema or a Pydantic model, got {}".format(type(output_schema))
                )

        final_obj = Action(original)  # type: Action
        final_obj.execution_info = execution_info_validator
        return final_obj

    if callable(input_schema):
        raise TypeError(
            "input schema should be a JSON or pydantic BaseModel, not a function/method, "
            + "did you decorate your action wrongly? use @action() instead of @action"
        )
    if any(key not in __action_kw_arguments__ for key in kwargs.keys()):
        raise ValueError(
            "Only 'safe', 'idempotent', 'synchronous' are allowed as keyword arguments, "
            + f"unknown arguments found {kwargs.keys()}"
        )
    inner._arguments = dict(
        input_schema=input_schema,
        output_schema=output_schema,
        state=state,
        kwargs=kwargs,
    )
    return inner