PyActor

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The minimalistic python actor middleware

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PyActor is a python actor middleware for an object oriented architecture constructed with the idea of getting two remote actors to quickly communicate in a very simple, lightweight and minimalistic way.

It supports two versions:

• Threading
• Gevent green threads

It also includes communication between machines using XMLRPC and a second version that uses RabbitMQ message system in a transparent way.

Installation

Install using:

python setup.py install

Check that works executing the examples:

cd examples
python sample1.py
...

Check also the docs for a tutorial:

Commits are build and tested automatically at Travis-CI.

See code coverage at codecov.io or coveralls.io

First steps

This library is implemented using two types of concurrence:

• 'thread' : classic threads
• 'green_thread' : Gevent

Green threads give a performance almost twice better.

You will need to specify which one you are going to use at the beginning of your script with set_context('TYPE'). Where type is one of the two keywords above.

Then, first of all, a Host is needed in order to create some actors. Use it to spawn actors by giving the class type of the actor to create and one string that will identify it among the host. See example:

h = create_host()
actor1 = h.spawn('id1', MyClass)

The class of an actor must have defined its methods in the _tell and _ask sets so they can be called through the proxy. In the _tell set will be named those methods meant to be asynchronous and in the _ask set, the synchronous ones. In this example we have a class MyClass with a sync method ask_me() and an async method tell_me():

class MyClass:
    _tell = {'tell_me'}
    _ask = {'ask_me'}
    def tell_me(self, msg):
        print(msg)
    def ask_me(self):
        return "hello back"

As you can see, the async method receives a message and simply prints it while the sync method returns a result. You can now call this methods from your main code:

actor1.tell_me("Hello")
print(actor1.ask_me())

Remote connections

Unlike other library solutions, PyActor supports remote communication between various machines by only giving an IP to the host. For example:

host = create_host('http://127.0.0.1:1277/')

And this host is online, so the other machine only needs to lookup for it:

host = create_host('http://127.0.0.1:1679')
remote_host = host.lookup_url('http://127.0.0.1:1277/', Host)

Or directly get one of its actors:

c = host.lookup_url('http://127.0.0.1:1277/id1', 'MyClass', 'module')

Tutorial

PyActor has many examples and a tutorial explaining all its features. This examples can be found in the 'pyactor/examples' directory of the project. They are also explained in the documentation as a tutorial, hosted at readthedocs.org.