sirabus 0.7.0

Service Bus application pattern for Python with support for multiple messaging protocols.

SiraBus

SiraBus is a simple opinionated library for publishing and subscribing to events in an asynchronous and type-safe manner (to the extent that type safety can be achieved in Python).

Users publish events to an IPublishEvents interface, and users can subscribe to events by passing instances of an IHandleEvents interface to a ServiceBus implementation.

There's a TopographyBuilder that allows you to build a service bus topology, which is a declaration of queues and exchanges (based on transport protocol) that the service bus will use. This is useful for setting up the service bus in a production environment.

Example Usage

from sirabus import HierarchicalTopicMap, IHandleEvents
from sirabus.servicebus.amqp_servicebus import AmqpServiceBus, AmqpServiceBusConfiguration
import asyncio


class MyEventHandler(IHandleEvents):
    async def handle(self, event, headers):
        print(f"Handling event: {event} with headers: {headers}")


topic_map = HierarchicalTopicMap()
config = (AmqpServiceBusConfiguration.default()
    .with_amqp_url("amqp://guest:guest@localhost/")
    .with_topic_map(topic_map=topic_map)
    .with_handlers(MyEventHandler()))
# It can be further configured with SSL options, prefetch count, etc.
service_bus = AmqpServiceBus(
    configuration=config
)
asyncio.run(service_bus.run())

The run method starts the service bus and begins consuming messages from RabbitMQ. The stop method should be called to gracefully shut down the service bus and close the connection to RabbitMQ.

The message handling feature sets up a simple example of how to use the library. It sets up a service bus, registers a handler for a specific event type, and then publishes an event. The handler receives the event and processes it.

Supported Message Transport Protocols

SiraBus supports the following message transport protocols:

Protocol	Description
In-Memory	For local development and testing.
AMQP	For production use with RabbitMQ.
SQS	For production use with AWS SQS.
Redis	For production use with Redis.

Specific Topics

• Service Bus: Overview of the service bus and its components.
• Hierarchical Topics: Explanation of hierarchical topics and how to use them.
• Event Handling: How to handle events using the service bus.
• Command Handling: How to handle commands using the service bus.