Domain Events

A lightweight library with an implementation of Pub-Sub.

Install

pipenv install domain-events

or

pip install domain-events

Usage

In order to have the pub-sub working in your application, you'll need to write your own subscribers and to subscribe them to the publisher.

domain-events provides an interface for subscribers that needs to be implemented by your own subscribers in the first place. Two methods are mandatory: handle(self, event) and _events_subscribed_to(self). Following is an example of how to do it.

from domain_events import Subscriber


class ExampleSubscriber(Subscriber):

    def handle(self, event):
      #  Logic to handle the occurring event

    def _events_subscribed_to(self):
      """ Return the tuple of events it is subscribed to. """

      return (AnEvent, AnotherEvent)

Once the subscriber is implemented, you'll need to subscribe it to the event publisher.

from domain_events import Publisher

Publisher().subscribe(ExampleSubscriber())

Now, in order to publish an event, just call the publish method on the Publisher with one of your domain events.

from domain_events import Event, Publisher


class AnEvent(Event):
    pass

Publisher().publish(AnEvent())

The event will be passed on to the proper subscribers.

Publishing to PyPI

Follow these steps to publish a new version of the package to PyPI:

1. Update the version number in setup.py

2. Install build tools (if not already installed):

   pip install build twine
   

3. Build the distribution packages:

   python -m build
   

   This creates both source distribution (.tar.gz) and wheel (.whl) in the dist/ directory.

4. Verify the build:

   twine check dist/*
   

5. Upload to PyPI using twine:

   twine upload dist/*
   

   Note: Use an API token instead of username/password. Configure it in ~/.pypirc:

   [pypi]
   username = __token__
   password = pypi-YOUR-API-TOKEN-HERE
   

6. Clean up the build artifacts (optional):

   rm -rf build/ dist/ *.egg-info/
   

Best Practices

• Use version tags: After publishing, tag the release in git:

  git tag -a X.Y.Z -m "Release X.Y.Z"
  git push origin --tags
  

Prerequisites

• You need a PyPI account with the appropriate permissions to upload this package