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Metadata-Version: 2.1
Name: async-timeout
Version: 4.0.2
Summary: Timeout context manager for asyncio programs
Home-page: https://github.com/aio-libs/async-timeout
Author: Andrew Svetlov <[email protected]>
Author-email: [email protected]
License: Apache 2
Project-URL: Chat: Gitter, https://gitter.im/aio-libs/Lobby
Project-URL: CI: GitHub Actions, https://github.com/aio-libs/async-timeout/actions
Project-URL: Coverage: codecov, https://codecov.io/github/aio-libs/async-timeout
Project-URL: GitHub: issues, https://github.com/aio-libs/async-timeout/issues
Project-URL: GitHub: repo, https://github.com/aio-libs/async-timeout
Platform: UNKNOWN
Classifier: Development Status :: 5 - Production/Stable
Classifier: Topic :: Software Development :: Libraries
Classifier: Framework :: AsyncIO
Classifier: Intended Audience :: Developers
Classifier: License :: OSI Approved :: Apache Software License
Classifier: Programming Language :: Python
Classifier: Programming Language :: Python :: 3
Classifier: Programming Language :: Python :: 3 :: Only
Classifier: Programming Language :: Python :: 3.6
Classifier: Programming Language :: Python :: 3.7
Classifier: Programming Language :: Python :: 3.8
Classifier: Programming Language :: Python :: 3.9
Classifier: Programming Language :: Python :: 3.10
Requires-Python: >=3.6
Description-Content-Type: text/x-rst
License-File: LICENSE
Requires-Dist: typing-extensions (>=3.6.5) ; python_version < "3.8"

async-timeout
=============
.. image:: https://travis-ci.com/aio-libs/async-timeout.svg?branch=master
    :target: https://travis-ci.com/aio-libs/async-timeout
.. image:: https://codecov.io/gh/aio-libs/async-timeout/branch/master/graph/badge.svg
    :target: https://codecov.io/gh/aio-libs/async-timeout
.. image:: https://img.shields.io/pypi/v/async-timeout.svg
    :target: https://pypi.python.org/pypi/async-timeout
.. image:: https://badges.gitter.im/Join%20Chat.svg
    :target: https://gitter.im/aio-libs/Lobby
    :alt: Chat on Gitter

asyncio-compatible timeout context manager.


Usage example
-------------


The context manager is useful in cases when you want to apply timeout
logic around block of code or in cases when ``asyncio.wait_for()`` is
not suitable. Also it's much faster than ``asyncio.wait_for()``
because ``timeout`` doesn't create a new task.

The ``timeout(delay, *, loop=None)`` call returns a context manager
that cancels a block on *timeout* expiring::

   async with timeout(1.5):
       await inner()

1. If ``inner()`` is executed faster than in ``1.5`` seconds nothing
   happens.
2. Otherwise ``inner()`` is cancelled internally by sending
   ``asyncio.CancelledError`` into but ``asyncio.TimeoutError`` is
   raised outside of context manager scope.

*timeout* parameter could be ``None`` for skipping timeout functionality.


Alternatively, ``timeout_at(when)`` can be used for scheduling
at the absolute time::

   loop = asyncio.get_event_loop()
   now = loop.time()

   async with timeout_at(now + 1.5):
       await inner()


Please note: it is not POSIX time but a time with
undefined starting base, e.g. the time of the system power on.


Context manager has ``.expired`` property for check if timeout happens
exactly in context manager::

   async with timeout(1.5) as cm:
       await inner()
   print(cm.expired)

The property is ``True`` if ``inner()`` execution is cancelled by
timeout context manager.

If ``inner()`` call explicitly raises ``TimeoutError`` ``cm.expired``
is ``False``.

The scheduled deadline time is available as ``.deadline`` property::

   async with timeout(1.5) as cm:
       cm.deadline

Not finished yet timeout can be rescheduled by ``shift_by()``
or ``shift_to()`` methods::

   async with timeout(1.5) as cm:
       cm.shift(1)  # add another second on waiting
       cm.update(loop.time() + 5)  # reschedule to now+5 seconds

Rescheduling is forbidden if the timeout is expired or after exit from ``async with``
code block.


Installation
------------

::

   $ pip install async-timeout

The library is Python 3 only!



Authors and License
-------------------

The module is written by Andrew Svetlov.

It's *Apache 2* licensed and freely available.