03: Async Actions

Source: examples/03_async_actions.py

This example demonstrates async entry and exit actions and verifies execution order using fire_async(...).

Run

uv run python examples/03_async_actions.py

What This Example Covers

• Async handlers with on_entry_async(...) and on_exit_async(...)
• Async trigger firing with await sm.fire_async(...)
• Transition ordering across async actions
• Assertion-based verification of expected behavior

Key APIs Used

async_machine.configure(State.EXECUTING).on_entry_async(
    on_entry_executing
).on_exit_async(on_exit_executing).permit(Trigger.FINISH, State.FINISHED)

await async_machine.fire_async(Trigger.START)
await async_machine.fire_async(Trigger.FINISH)

Notes

• The script is runnable directly and is also decorated for pytest-asyncio.
• Use this pattern when any guard, action, or callback is asynchronous.