pyeventbus 0.5

Description:

pyeventbus 0.5

pyeventbus is a publish/subscribe event bus for Python 2.7.

simplifies the communication between python classes
decouples event senders and receivers
performs well threads, greenlets, queues and concurrent processes
avoids complex and error-prone dependencies and life cycle issues
makes code simpler
has advanced features like delivery threads, workers and spawning different processes, etc.
is tiny (3KB archive)

pyeventbus in 3 steps:

Define events:
class MessageEvent:
# Additional fields and methods if needed
def __init__(self):
pass

Prepare subscribers: Declare and annotate your subscribing method, optionally specify a thread mode:
from pyeventbus import *

@subscribe(onEvent=MessageEvent)
def func(self, event):
# Do something
pass
Register your subscriber. For example, if you want to register a class in Python:
from pyeventbus import *

class MyClass:
def __init__(self):
pass

def register(self, myclass):
PyBus.Instance().register(myclass, self.__class__.__name__)

# then during initilization

myclass = MyClass()
myclass.register(myclass)

Post events:
from pyeventbus import *

class MyClass:
def __init__(self):
pass

def register(self, myclass):
PyBus.Instance().register(myclass, self.__class__.__name__)

def postingAnEvent(self):
PyBus.Instance().post(MessageEvent())

myclass = MyClass()
myclass.register(myclass)
myclass.post()


Modes: pyeventbus can run the subscribing methods in 5 different modes

POSTING:
Runs the method in the same thread as posted. For example, if an event is posted from main thread, the subscribing method also runs in the main thread. If an event is posted in a seperate thread, the subscribing method runs in the same seperate method

This is the default mode, if no mode has been provided::

@subscribe(threadMode = Mode.POSTING, onEvent=MessageEvent)
def func(self, event):
# Do something
pass

PARALLEL:
Runs the method in a seperate python thread::

@subscribe(threadMode = Mode.PARALLEL, onEvent=MessageEvent)
def func(self, event):
# Do something
pass

GREENLET:
Runs the method in a greenlet using gevent library::

@subscribe(threadMode = Mode.GREENLET, onEvent=MessageEvent)
def func(self, event):
# Do something
pass

BACKGROUND:
Adds the subscribing methods to a queue which is executed by workers::

@subscribe(threadMode = Mode.BACKGROUND, onEvent=MessageEvent)
def func(self, event):
# Do something
pass



CONCURRENT:
Runs the method in a seperate python process::

@subscribe(threadMode = Mode.CONCURRENT, onEvent=MessageEvent)
def func(self, event):
# Do something
pass


Adding pyeventbus to your project:
pip install pyeventbus
Example:
git clone https://github.com/n89nanda/pyeventbus.git

cd pyeventbus

virtualenv venv

source venv/bin/activate

pip install pyeventbus

python example.py
Benchmarks and Performance:
Refer /pyeventbus/tests/benchmarks.txt for performance benchmarks on CPU, I/O and networks heavy tasks.

Run /pyeventbus/tests/test.sh to generate the same benchmarks.
Inspiration

Inspired by Eventbus from greenrobot: https://github.com/greenrobot/EventBus