asyncx.EventLoopThread

class asyncx.EventLoopThread(loop_policy=None, daemon=False, start=False)

An event loop thread that provides thread-safe utility functions.

Note

The thread cannot be started more than once because of the constraints of threading.Thread. The class raises RuntimeError if it is already terminated.

Example

>>> async def _get_ident() -> int:
...     return threading.get_ident()
...
>>> thread = EventLoopThread()
>>> with thread:
...     main, sub = await asyncio.gather(
...         _get_ident(),
...         thread.run_coroutine(_get_ident()),
...     )
>>> main == sub
False

Parameters

• loop_policy (Optional[asyncio.AbstractEventLoopPolicy]) –

• daemon (bool) –

• start (bool) –

Return type

None

__init__(loop_policy=None, daemon=False, start=False)

Creates a new event loop thread.

Parameters

• loop_policy (Optional[asyncio.events.AbstractEventLoopPolicy]) – A asyncio.AbstractEventLoopPolicy object to be used for creating a new event loop. If None is specified, asyncio.get_event_loop_policy() is used to get the policy.

• daemon (bool) –

  If True is specified, the thread is created with daemon=True. Refer to threading.Thread.daemon for further details.

• start (bool) – If True is specified, the thread is started immediately.

Return type

None

Methods

__init__([loop_policy, daemon, start])	Creates a new event loop thread.
getName()
isAlive()	Return whether the thread is alive.
isDaemon()
is_alive()	Return whether the thread is alive.
join([timeout])	Wait until the thread terminates.
run()	Method representing the thread's activity.
run_coroutine(coro, *[, loop])	Submit a coroutine in a new thread and waits for its completion in a given loop.
run_coroutine_concurrent(coro)	Submit a coroutine in the event loop.
setDaemon(daemonic)
setName(name)
shutdown([join])	Shutdown the running event loop to terminate the thread.
start()	Start the thread and wait for a new event loop to be ready.

Attributes

daemon	A boolean value indicating whether this thread is a daemon thread.
ident	Thread identifier of this thread or None if it has not been started.
loop	Get an event loop of the running thread.
name	A string used for identification purposes only.
native_id	Native integral thread ID of this thread, or None if it has not been started.

property loop: asyncio.events.AbstractEventLoop

Get an event loop of the running thread.

The thread should be running. The method will raise RuntimeError if the thread is not running.

run_coroutine(coro, *, loop=None)

Submit a coroutine in a new thread and waits for its completion in a given loop.

Parameters

• coro (Coroutine[Any, Any, TReturn]) – A Coroutine object to run.

• loop (Optional[asyncio.AbstractEventLoop]) – An event loop to wait for the completion of coro.

Returns

A asyncio.Future object that returns the execution result of a given coroutine.

Return type

asyncio.Future[TReturn]

run_coroutine_concurrent(coro)

Submit a coroutine in the event loop.

Parameters

coro (Coroutine[Any, Any, TReturn]) – A Coroutine object to run.

Returns

A concurrent.future.Future object that returns the execution result of a given coroutine.

Return type

concurrent.futures.Future[TReturn]

shutdown(join=True)

Shutdown the running event loop to terminate the thread.

If the event loop is not running, it returns immediately.

Parameters

join (bool) – If True is specified, the method waits for the thread to be terminated.

Raises

RumtimeError – The method raises a RuntimeError if join = True and the method is called by the same thread as self.loop in order to avoid a deadlock. See threading.Thread.join for further details.

Return type

None

start()

Start the thread and wait for a new event loop to be ready.

If the thread is already started, it returns immediately.

Raises

RuntimeError – If the thread is already terminated.

Return type

None