How to use the chaostoolkit.errors.InvalidPlan function in chaostoolkit

def test_action_needs_a_name():
    step = {
        "action": {
            "parameters": {
                "name": "cherrypy-webapp"
            }
        }
    }

    with pytest.raises(InvalidPlan) as excinfo:
        apply_action(step, layers)

    assert "action requires a name" in str(excinfo)

def apply_steady_probe(step: Dict[str, Any], layers: Dict[str, Layer]):
    """
    Apply the steady probe found in this step. If none is defined, does
    nothing.

    When the name of the probe is not recognized, fails the call with an
    :exc:`UnknownProbe` exception.
    """
    probe = get_probe_from_step(step, "steady")
    if probe is None:
        return

    if "name" not in probe:
        raise InvalidPlan("steady probe requires a probe name to apply")

    if "layer" not in probe:
        raise InvalidPlan("steady probe requires the target layer to be set")

    if probe:
        probe_name = probe.pop("name")
        layer = layers.get(probe["layer"])
        logger.info(" Applying steady probe '{name}'".format(name=probe_name))
        apply_probe(probe_name, probe, layer)

Apply the saction found in this step. If none is defined, does
    nothing.

    When the name of the probe is not recognized, fails the call with an
    :exc:`UnknownAction` exception.
    """
    action = step.get("action")
    if not action:
        return

    action_name = action.get("name")
    if not action_name:
        raise InvalidPlan("action requires a name")

    if "layer" not in action:
        raise InvalidPlan("action requires the target layer to be set")

    pause(action, "before")
    logger.info(" Executing action '{name}'".format(name=action_name))
    layer = layers.get(action["layer"])
    execute_action(action_name, action, layer)
    pause(action, "after")

"""
    Apply the steady probe found in this step. If none is defined, does
    nothing.

    When the name of the probe is not recognized, fails the call with an
    :exc:`UnknownProbe` exception.
    """
    probe = get_probe_from_step(step, "steady")
    if probe is None:
        return

    if "name" not in probe:
        raise InvalidPlan("steady probe requires a probe name to apply")

    if "layer" not in probe:
        raise InvalidPlan("steady probe requires the target layer to be set")

    if probe:
        probe_name = probe.pop("name")
        layer = layers.get(probe["layer"])
        logger.info(" Applying steady probe '{name}'".format(name=probe_name))
        apply_probe(probe_name, probe, layer)

def apply_close_probe(step: Dict[str, Any], layers: Dict[str, Layer]):
    """
    Apply the close probe found in this step. If none is defined, does
    nothing.

    When the name of the probe is not recognized, fails the call with an
    :exc:`UnknownProbe` exception.
    """
    probe = get_probe_from_step(step, "close")
    if probe is None:
        return

    if "name" not in probe:
        raise InvalidPlan("close probe requires a probe name to apply")

    if "layer" not in probe:
        raise InvalidPlan("close probe requires the target layer to be set")

    if probe:
        probe_name = probe.pop("name")
        layer = layers.get(probe["layer"])
        logger.info(" Applying close probe '{name}'".format(name=probe_name))
        apply_probe(probe_name, probe, layer)

"""
    Apply the close probe found in this step. If none is defined, does
    nothing.

    When the name of the probe is not recognized, fails the call with an
    :exc:`UnknownProbe` exception.
    """
    probe = get_probe_from_step(step, "close")
    if probe is None:
        return

    if "name" not in probe:
        raise InvalidPlan("close probe requires a probe name to apply")

    if "layer" not in probe:
        raise InvalidPlan("close probe requires the target layer to be set")

    if probe:
        probe_name = probe.pop("name")
        layer = layers.get(probe["layer"])
        logger.info(" Applying close probe '{name}'".format(name=probe_name))
        apply_probe(probe_name, probe, layer)