=========
aiosignal
=========

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Introduction
============

A project to manage callbacks in `asyncio` projects.

``Signal`` is a list of registered asynchronous callbacks.

The signal's life-cycle has two stages: after creation its content
could be filled by using standard list operations: ``sig.append()``
etc.

After you call ``sig.freeze()`` the signal is *frozen*: adding, removing
and dropping callbacks is forbidden.

The only available operation is calling the previously registered
callbacks by using ``await sig.send(data)``.

For concrete usage examples see the `Signals
<https://docs.aiohttp.org/en/stable/web_advanced.html#aiohttp-web-signals>
section of the `Web Server Advanced
<https://docs.aiohttp.org/en/stable/web_advanced.html>` chapter of the `aiohttp
documentation`_.


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

::

   $ pip install aiosignal

The library requires Python 3.6 or newer.


Documentation
=============

https://aiosignal.readthedocs.io/

Communication channels
======================

*aio-libs* google group: https://groups.google.com/forum/#!forum/aio-libs

Feel free to post your questions and ideas here.

*gitter chat* https://gitter.im/aio-libs/Lobby

Requirements
============

- Python >= 3.6
- frozenlist >= 1.0.0

License
=======

``aiosignal`` is offered under the Apache 2 license.

Source code
===========

The project is hosted on GitHub_

Please file an issue in the `bug tracker
<https://github.com/aio-libs/aiosignal/issues>`_ if you have found a bug
or have some suggestions to improve the library.

.. _GitHub: https://github.com/aio-libs/aiosignal
.. _aiohttp documentation: https://docs.aiohttp.org/