aiopubsub 2.1.5

Simple pubsub pattern for asyncio applications.

aiopubsub is only tested with Python 3.6. There are no plans to support older versions.

import asyncio
import aiopubsub
import logwood

async def main():
        logwood.basic_config()
        hub = aiopubsub.Hub()
        publisher = aiopubsub.Publisher(hub, prefix = aiopubsub.Key('a'))
        subscriber = aiopubsub.Subscriber(hub, 'subscriber_id')

        sub_key = aiopubsub.Key('a', 'b', '*')
        subscriber.subscribe(sub_key)

        pub_key = aiopubsub.Key('b', 'c')
        publisher.publish(pub_key, 'Hello subscriber')
        await asyncio.sleep(0.001) # Let the callback fire.
        # "('a', 'b', 'c') Hello subscriber" will be printed.

        key, message = await subscriber.consume()
        assert key == aiopubsub.Key('a', 'b', 'c')
        assert message == 'Hello subscriber'

        subscriber.remove_all_listeners()


asyncio.get_event_loop().run_until_complete(main())

or, instead of directly subscribing to the key, we can create a listener that will call a synchronous callback when a new message arrives.

def print_message(key, message):
        print(key, message)

subscriber.add_sync_listener(sub_key, print_message)

Or, if we have a coroutine callback we can create an asynchronous listener:

async def print_message(key, message):
        await asyncio.sleep(1)
        print(key, message)

subscriber.add_async_listener(sub_key, print_message)

Aiopubsub will use logwood if it is installed, otherwise it will default to the standard logging module. Note that logwood is required to run tests.

{
        "key": ("key", "of", "added", "subscriber"),
        "currentSubscriberCount": 2
}