aiomas 2.0.1

Description:

aiomas 2.0.1

aiomas – A library for multi-agent systems and RPC based on asyncio


aiomas is an easy-to-use library for request-reply channels, remote
procedure calls (RPC) and multi-agent systems (MAS). It’s written in pure
Python on top of asyncio.
Here are three simple examples that show the different layers of aiomas and
what they add on top of each other:
The request-reply channel has the lowest level of abstraction (but already
offers more then vanilla asyncio):
>>> import aiomas
>>>
>>>
>>> async def handle_client(channel):
... """Handle a client connection."""
... req = await channel.recv()
... print(req.content)
... await req.reply('cya')
... await channel.close()
>>>
>>>
>>> async def client():
... """Client coroutine: Send a greeting to the server and wait for a
... reply."""
... channel = await aiomas.channel.open_connection(('localhost', 5555))
... rep = await channel.send('ohai')
... print(rep)
... await channel.close()
>>>
>>>
>>> server = aiomas.run(aiomas.channel.start_server(('localhost', 5555), handle_client))
>>> aiomas.run(client())
ohai
cya
>>> server.close()
>>> aiomas.run(server.wait_closed())
The RPC layer adds remote procedure calls on top of it:
>>> import aiomas
>>>
>>>
>>> class MathServer:
... router = aiomas.rpc.Service()
...
... @router.expose
... def add(self, a, b):
... return a + b
...
>>>
>>> async def client():
... """Client coroutine: Call the server's "add()" method."""
... rpc_con = await aiomas.rpc.open_connection(('localhost', 5555))
... rep = await rpc_con.remote.add(3, 4)
... print('What’s 3 + 4?', rep)
... await rpc_con.close()
>>>
>>> server = aiomas.run(aiomas.rpc.start_server(('localhost', 5555), MathServer()))
>>> aiomas.run(client())
What’s 3 + 4? 7
>>> server.close()
>>> aiomas.run(server.wait_closed())
Finally, the agent layer hides some of the boilerplate code required to setup
the sockets and allows agent instances to easily talk with each other:
>>> import aiomas
>>>
>>> class TestAgent(aiomas.Agent):
... def __init__(self, container):
... super().__init__(container)
... print('Ohai, I am %s' % self)
...
... async def run(self, addr):
... remote_agent = await self.container.connect(addr)
... ret = await remote_agent.service(42)
... print('%s got %s from %s' % (self, ret, remote_agent))
...
... @aiomas.expose
... def service(self, value):
... return value
>>>
>>> c = aiomas.Container.create(('localhost', 5555))
>>> agents = [TestAgent(c) for i in range(2)]
Ohai, I am TestAgent('tcp://localhost:5555/0')
Ohai, I am TestAgent('tcp://localhost:5555/1')
>>> aiomas.run(until=agents[0].run(agents[1].addr))
TestAgent('tcp://localhost:5555/0') got 42 from TestAgentProxy('tcp://localhost:5555/1')
>>> c.shutdown()
aiomas is released under the MIT license. It requires Python 3.4 and above
and runs on Linux, OS X, and Windows.

Installation
aiomas requires Python >= 3.6 (or PyPy3 >= 5.10.0). It uses the JSON codec
by default and only has pure Python dependencies.
Install aiomas via pip by running:
$ pip install aiomas
You can enable the optional MsgPack codec or its Blosc compressed version
by installing the corresponding features (note, that you need a C compiler to
install them):
$ pip install aiomas[mp] # Enables the MsgPack codec
$ pip install aiomas[mpb] # Enables the MsgPack and MsgPackBlosc codecs


Features
aiomas just puts three layers of abstraction around raw TCP / unix domain
sockets provided by asyncio:

Agents and agent containers:
The top-layer provides a simple base class for your own agents. All agents
live in a container.
Containers take care of creating agent instances and performing the
communication between them.
The container provides a clock for the agents. This clock can either be
synchronized with the real (wall-clock) time or be set by an external process
(e.g., other simulators).

RPC:
The rpc layer implements remote procedure calls which let you call methods
on remote objects nearly as if they were normal objects:
Instead of ret = obj.meth(arg) you write ret = await obj.meth(arg).

Request-reply channel:
The channel layer is the basis for the rpc layer. It sends JSON or
MsgPack encoded byte strings over TCP or unix domain sockets. It also maps
replies (of success or failure) to their corresponding request.


Other features:

TLS support for authorization and encrypted communication.
Interchangeable and extensible codecs: JSON and MsgPack (the latter
optionally compressed with Blosc) are built-in. You can add custom codecs or
write (de)serializers for your own objects to extend a codec.
Deterministic, emulated sockets: A LocalQueue transport lets you send and
receive message in a deterministic and reproducible order within a single
process. This helps testing and debugging distributed algorithms.


Planned features
Some ideas for future releases:

Optional automatic re-connect after connection loss




Contribute

Issue Tracker: https://gitlab.com/sscherfke/aiomas/issues
Source Code: https://gitlab.com/sscherfke/aiomas

Set-up a development environment with:
$ virtualenv -p `which python3` aiomas
$ pip install -r requirements-setup.txt
Run the tests with:
$ pytest
$ # or
$ tox


Support

Documentation: https://aiomas.readthedocs.io/en/latest/
Mailing list: https://groups.google.com/forum/#!forum/python-tulip
Stack Overflow: http://stackoverflow.com/questions/tagged/aiomas
IRC: #asyncio



License
The project is licensed under the MIT license.



Changelog

2.0.1 – 2017-12-29

[CHANGE] Restore support for Python 3.5 so that the docs on Read the Docs
build again.



2.0.0 – 2017-12-28

[BREAKING] Converted to f-Strings and async/await syntax. The
minimum required Python versions are now Python 3.6 and PyPy3 5.10.0.
[BREAKING] Removed aiomas.util.async() and aiomas.util.create_task().
[CHANGE] Move from Bitbucket and Mercurial to GitLab and Git.
[FIX] Adjust to asyncio changes and explicitly pass references to the current
event loop where necessary.

You can find information about older versions in the documentation.



Authors
The original author of aiomas is Stefan Scherfke.
The initial development has kindly been supported by OFFIS.