circuits 3.2.3
Asynchronous Component based Event Application Framework
License: MIT
Requires Python: >=3.7
Keywords: event framework distributed concurrent component asynchronous

.. _Python Programming Language: http://www.python.org/
.. _#circuits IRC Channel: https://web.libera.chat/#circuits
.. _Libera.Chat IRC Network: https://libera.chat
.. _Python Standard Library: http://docs.python.org/library/
.. _MIT License: http://www.opensource.org/licenses/mit-license.php
.. _Create an Issue: https://github.com/circuits/circuits/issues/new
.. _Mailing List: http://groups.google.com/group/circuits-users
.. _Website: http://circuitsframework.com/
.. _PyPi: http://pypi.python.org/pypi/circuits
.. _Documentation: http://circuits.readthedocs.org/en/latest/
.. _Downloads: https://github.com/circuits/circuits/releases
.. _Ask a Question: http://stackoverflow.com/questions/ask
.. _Stackoverflow: http://stackoverflow.com/

.. image:: https://github.com/circuits/circuits/actions/workflows/python-app.yml/badge.svg
   :target: https://github.com/circuits/circuits/actions/workflows/python-app.yml
   :alt: Build Status

.. image:: https://codecov.io/gh/circuits/circuits/branch/master/graph/badge.svg
  :target: https://codecov.io/gh/circuits/circuits
  :alt: Coverage

circuits is a **Lightweight** **Event** driven and **Asynchronous**
**Application Framework** for the `Python Programming Language`_
with a strong **Component** Architecture.

circuits also includes a lightweight, high performance and scalable
HTTP/WSGI compliant web server as well as various I/O and Networking
components.

- `Website`_
- `Downloads`_
- `Documentation`_

Got questions?

- `Ask a Question`_ (Tag it: ``circuits-framework``)


Examples
--------

Hello
.....


.. code:: python

    #!/usr/bin/env python

    """circuits Hello World"""

    from circuits import Component, Event


    class hello(Event):
        """hello Event"""


    class App(Component):

        def hello(self):
            """Hello Event Handler"""

            print("Hello World!")

        def started(self, component):
            """Started Event Handler

            This is fired internally when your application starts up and can be used to
            trigger events that only occur once during startup.
            """

            self.fire(hello())  # Fire hello Event

            raise SystemExit(0)  # Terminate the Application

    App().run()


Echo Server
...........


.. code:: python

    #!/usr/bin/env python

    """Simple TCP Echo Server

    This example shows how you can create a simple TCP Server (an Echo Service)
    utilizing the builtin Socket Components that the circuits library ships with.
    """

    from circuits import handler, Debugger
    from circuits.net.sockets import TCPServer


    class EchoServer(TCPServer):

        @handler("read")
        def on_read(self, sock, data):
            """Read Event Handler

            This is fired by the underlying Socket Component when there has been
            new data read from the connected client.

            ..note :: By simply returning, client/server socket components listen
                      to ValueChagned events (feedback) to determine if a handler
                      returned some data and fires a subsequent Write event with
                      the value returned.
            """

            return data

    # Start and "run" the system.
    # Bind to port 0.0.0.0:8000
    app = EchoServer(8000)
    Debugger().register(app)
    app.run()


Hello Web
.........


.. code:: python

    #!/usr/bin/env python

    from circuits.web import Server, Controller


    class Root(Controller):

        def index(self):
            """Index Request Handler

            Controller(s) expose implicitly methods as request handlers.
            Request Handlers can still be customized by using the ``@expose``
            decorator. For example exposing as a different path.
            """

            return "Hello World!"

    app = Server(("0.0.0.0", 8000))
    Root().register(app)
    app.run()


More `examples <https://github.com/circuits/circuits/tree/master/examples>`_...



Features
--------

- event driven
- concurrency support
- component architecture
- asynchronous I/O components
- no required external dependencies
- full featured web framework (circuits.web)
- coroutine based synchronization primitives


Requirements
------------

- circuits has no dependencies beyond the `Python Standard Library`_.


Supported Platforms
-------------------

- Linux, FreeBSD, Mac OS X, Windows
- Python 3.7, 3.8, 3.9, 3.10, 3.11, 3.12
- pypy (the newer the better)


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

The simplest and recommended way to install circuits is with pip.
You may install the latest stable release from PyPI with pip::

    $ pip install circuits

If you do not have pip, you may use easy_install::

    $ easy_install circuits

Alternatively, you may download the source package from the
`PyPi`_ or the `Downloads`_ extract it and install using::

    $ python setup.py install


.. note::
    You can install the `development version
    <https://github.com/circuits/circuits/archive/master.zip#egg=circuits-dev>`_
    via ``pip install circuits==dev``.


License
-------

circuits is licensed under the `MIT License`_.


Feedback
--------

We welcome any questions or feedback about bugs and suggestions on how to
improve circuits.

Let us know what you think about circuits. `@pythoncircuits <http://twitter.com/pythoncircuits>`_.

Do you have suggestions for improvement? Then please `Create an Issue`_
with details of what you would like to see. I'll take a look at it and
work with you to either incorporate the idea or find a better solution.


Community
---------

There are also several places you can reach out to the circuits community:

- `Mailing List`_
- `#circuits IRC Channel`_ on the `Libera.Chat IRC Network`_
- `Ask a Question`_ on `Stackoverflow`_ (Tag it: ``circuits-framework``)

----

Disclaimer
----------

Whilst I (James Mills) continue to contribute and maintain the circuits project
I do not represent the interests or business of my employer Facebook Inc. The
contributions I make are of my own free time and have no bearing or relevance
to Facebook Inc.