labthings_fastapi.descriptors.action

Define an object to represent an Action, as a descriptor.

Module Contents

Classes

ActionDescriptor

Data

ACTION_POST_NOTICE

ACTION_GET_DESCRIPTION

API

labthings_fastapi.descriptors.action.ACTION_POST_NOTICE = <Multiline-String>
labthings_fastapi.descriptors.action.ACTION_GET_DESCRIPTION = <Multiline-String>
class labthings_fastapi.descriptors.action.ActionDescriptor(func: Callable, response_timeout: float = 1, retention_time: float = 300)
__init__(func: Callable, response_timeout: float = 1, retention_time: float = 300)
__get__(obj: Optional[labthings_fastapi.thing.Thing], type=None) → labthings_fastapi.thing_description.model.Union[labthings_fastapi.descriptors.action.ActionDescriptor, Callable]

The function, bound to an object as for a normal method.

This currently doesn’t validate the arguments, though it may do so in future. In its present form, this is equivalent to a regular Python method, i.e. all we do is supply the first argument, self.

If obj is None, the descriptor is returned, so we can get the descriptor conveniently as an attribute of the class.

property name

The name of the wrapped function

property title

A human-readable title

property description

A description of the action

_observers_set(obj)

A set used to notify changes

emit_changed_event(obj, status)

Notify subscribers that the action status has changed

This function is run from within the Invocation thread that is created when an action is called. It must be run from this thread as it is communicating with the event loop via an asyncio blocking portal.

Raises:

NotConnectedToServerError – if the Thing calling the action is not connected to a server with a running event loop.

async emit_changed_event_async(obj: labthings_fastapi.thing.Thing, value: Any)

Notify subscribers that the action status has changed

add_to_fastapi(app: fastapi.FastAPI, thing: labthings_fastapi.thing.Thing)

Add this action to a FastAPI app, bound to a particular Thing.

action_affordance(thing: labthings_fastapi.thing.Thing, path: Optional[str] = None) → labthings_fastapi.thing_description.model.ActionAffordance

Represent the property in a Thing Description.