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.. aiojobs documentation master file, created by
sphinx-quickstart on Sat Jul 1 15:24:45 2017.
You can adapt this file completely to your liking, but it should at least
contain the root `toctree` directive.
aiojobs: Jobs scheduler for managing background task
====================================================
The library gives controlled way for scheduling background tasks for
:mod:`asyncio` applications.
Installation
------------
.. code-block:: bash
$ pip3 install aiojobs
Usage example
-------------
.. code-block:: python
import asyncio
import aiojobs
async def coro(timeout):
await asyncio.sleep(timeout)
async def main():
async with aiojobs.Scheduler() as scheduler:
for i in range(100):
# spawn jobs
await scheduler.spawn(coro(i/10))
await asyncio.sleep(5.0)
# not all scheduled jobs are finished at the moment
# Exit from context will gracefully wait on tasks before closing
# any remaining spawned jobs
asyncio.run(main())
For further information read :ref:`aiojobs-quickstart`,
:ref:`aiojobs-intro` and :ref:`aiojobs-api`.
Shielding tasks with a scheduler
--------------------------------
It is typically recommended to use :func:`asyncio.shield` to protect tasks
from cancellation. However, the inner shielded tasks can't be tracked and
are therefore at risk of being cancelled during application shutdown.
To resolve this issue aiojobs includes a :meth:`aiojobs.Scheduler.shield`
method to shield tasks while also keeping track of them in the scheduler.
In combination with the :meth:`aiojobs.Scheduler.wait_and_close` method,
this allows shielded tasks the required time to complete successfully
during application shutdown.
For example:
.. code-block:: python
import asyncio
import aiojobs
from contextlib import suppress
async def important():
print("START")
await asyncio.sleep(5)
print("DONE")
async def run_something(scheduler):
# If we use asyncio.shield() here, then the task doesn't complete and DONE is never printed.
await scheduler.shield(important())
async def main():
async with aiojobs.Scheduler() as scheduler:
t = asyncio.create_task(run_something(scheduler))
await asyncio.sleep(0.1)
t.cancel()
with suppress(asyncio.CancelledError):
await t
asyncio.run(main())
Integration with aiohttp.web
----------------------------
.. code-block:: python
from aiohttp import web
from aiojobs.aiohttp import setup, spawn
import aiojobs
async def handler(request):
await spawn(request, coro())
return web.Response()
app = web.Application()
app.router.add_get('/', handler)
setup(app)
or just
.. code-block:: python
from aiojobs.aiohttp import atomic
@atomic
async def handler(request):
return web.Response()
Source code
-----------
The project is hosted on GitHub: https://github.com/aio-libs/aiojobs
Please feel free to file an issue on the bug tracker if you have found
a bug or have some suggestion in order to improve the library.
Communication channels
----------------------
*Gitter Chat* https://gitter.im/aio-libs/Lobby
We support `Stack Overflow <https://stackoverflow.com>`_.
Please add *python-asyncio* or *aiohttp* tag to your question there.
Author and License
-------------------
The ``aiojobs`` package is written by Andrew Svetlov.
It's *Apache 2* licensed and freely available.
.. toctree::
:maxdepth: 2
:caption: Contents:
quickstart
intro
api
Indices and tables
==================
* :ref:`genindex`
* :ref:`modindex`
* :ref:`search`
|
