Feature: asyncio node

[nadavelkabets]

Motivation

Current wait_set based executors are highly inefficient and don’t integrate cleanly with Python’s asyncio ecosystem.
Examples of inefficiencies in the wait_set executor:

• Reoccurring construction of the wait set
• Revisiting blocked tasks every iteration
• Busy looping while a callback group is blocking

Advantages of integrating with asyncio:

• Better support for asynchronous code – take advantage of many existing features like call_later(), sleep(), and task exception handling
• Easy integration with large Python libraries – FastAPI, pyserial-asyncio, pytransitions, aiohttp, python-can, etc.
• High performance – asyncio is already far more optimized than the existing wait_set executor, and libraries like uvloop are available for even higher performance, matching the current cpp implementation of the EventsExecutor
• Reduction in code duplication - lower maintenance costs and library complexity by transitioning to a built in event loop implementation

Related Issues & PRs

• async wait/sleep implementation #1234 – async wait/sleep implementation
• Tasks that raise an exception crash the entire executor, even when the exception is caught #1098 – Tasks that raise an exception crash the entire executor
• Runtime error when a long async callback is triggered #962 – Runtime error when a long async callback is triggered
• Ignore exceptions raised in user created tasks #1395 – Ignore exceptions raised in user-created tasks
• Enable limited use of asyncio with executors #971 – Enable limited use of asyncio with executors

[wjwwood]

Going to discuss in the Client Library Working Group.

[ros-discourse]

This issue has been mentioned on ROS Discourse. There might be relevant details there:

https://discourse.ros.org/t/next-client-library-wg-meeting-friday-30th-may-2025-8am-pt/44015/1

[nadavelkabets]

Resolved by #1620