h-message-bus 0.0.38

Message bus integration for HAI

H Message Bus

A message bus integration for HAI applications based on NATS.io

Overview

H Message Bus provides a robust, asynchronous messaging infrastructure built on NATS.io for HAI applications. It enables seamless communication between components through a publish-subscribe pattern, supporting both fire-and-forget messaging and request-response patterns.

Features

• Asynchronous Communication: Built for modern, non-blocking I/O operations
• Flexible Message Routing: Publish and subscribe to specific topics
• High Reliability: Automatic reconnection handling and configurable timeouts
• Simple API: Focus on core messaging functionality with minimal dependencies

Installation

pip install h_message_bus

Requirements

• Python 3.10+
• NATS.io server (can be run via Docker)

Topics

H Message Bus includes predefined topics following the convention: hai.[source].[destination].[action]

Available topics:

Topic Constant	Topic String	Description
Topic.AI_SEND_TG_CHAT_MESSAGE	hai.ai.tg.chat.send	AI sending message to Telegram chat
Topic.AI_VECTORS_SAVE	hai.ai.vectors.save	AI saving data to vector database
Topic.AI_VECTORS_QUERY	hai.ai.vectors.query	AI querying vector database
Topic.TG_SEND_AI_CHAT_MESSAGE	hai.tg.ai.chat.send	Telegram sending message to AI

You can use these predefined topics or create your own topic strings.

Quick Start

Start a NATS Server

The easiest way to get started is with Docker:

docker-compose up -d

Create a Publisher

import asyncio
import uuid
from h_message_bus import NatsConfig, NatsPublisherAdapter, HaiMessage, Topic

async def main():
    # Configure NATS connection
    config = NatsConfig(server="nats://localhost:4222")
    
    # Create publisher adapter
    publisher = NatsPublisherAdapter(config)
    
    # Connect to NATS
    await publisher.connect()
    
    # Create and publish a message using a predefined topic
    message = HaiMessage(
        message_id=str(uuid.uuid4()),
        sender="service-a",
        topic=Topic.TG_SEND_AI_CHAT_MESSAGE,
        payload={"text": "Hello AI, this is a message from Telegram", "chat_id": 12345}
    )
    
    # Publish message
    await publisher.publish(message)
    
    # Clean up
    await publisher.close()

if __name__ == "__main__":
    asyncio.run(main())

Create a Subscriber

import asyncio
from h_message_bus import NatsConfig, NatsSubscriberAdapter, HaiMessage, Topic

async def message_handler(message: HaiMessage):
    print(f"Received message: {message.message_id}")
    print(f"From: {message.sender}")
    print(f"Topic: {message.topic}")
    print(f"Payload: {message.payload}")

async def main():
    # Configure NATS connection
    config = NatsConfig(server="nats://localhost:4222")
    
    # Create subscriber
    subscriber = NatsSubscriberAdapter(config)
    
    # Connect to NATS
    await subscriber.connect()
    
    # Subscribe to a topic
    await subscriber.subscribe(Topic.TG_SEND_AI_CHAT_MESSAGE, message_handler)
    
    # Keep the application running
    try:
        print("Subscriber running. Press Ctrl+C to exit.")
        while True:
            await asyncio.sleep(1)
    except KeyboardInterrupt:
        # Clean up
        await subscriber.close()

if __name__ == "__main__":
    asyncio.run(main())

Advanced Usage

Request-Response Pattern

import asyncio
import uuid
from h_message_bus import NatsConfig, NatsPublisherAdapter, HaiMessage, Topic

async def main():
    config = NatsConfig(server="nats://localhost:4222")
    publisher = NatsPublisherAdapter(config)
    
    # Connect to NATS
    await publisher.connect()
    
    request_message = HaiMessage(
        message_id=str(uuid.uuid4()),
        sender="client-service",
        topic=Topic.AI_VECTORS_QUERY,
        payload={"query": "find similar documents", "limit": 10}
    )
    
    # Send request and wait for response (with timeout)
    response = await publisher.request(request_message, timeout=5.0)
    
    if response:
        print(f"Received response: {response.payload}")
    else:
        print("Request timed out")
    
    await publisher.close()

if __name__ == "__main__":
    asyncio.run(main())

Creating a Service with Request Handler

import asyncio
import uuid
from h_message_bus import NatsConfig, NatsSubscriberAdapter, NatsPublisherAdapter, HaiMessage, Topic

async def request_handler(request: HaiMessage):
    print(f"Received request: {request.message_id}")
    print(f"Payload: {request.payload}")
    
    # Process the request
    result = {"status": "success", "data": {"result": 42}}
    
    # Create a response message
    return HaiMessage(
        message_id=str(uuid.uuid4()),
        sender="service-b",
        topic=f"{request.topic}.response",
        payload=result,
        correlation_id=request.message_id
    )

async def main():
    # Configure NATS connection
    config = NatsConfig(server="nats://localhost:4222")
    
    # Create subscriber for handling requests
    subscriber = NatsSubscriberAdapter(config)
    publisher = NatsPublisherAdapter(config)
    
    # Connect to NATS
    await subscriber.connect()
    await publisher.connect()
    
    # Register request handler for vector database queries
    await subscriber.subscribe_with_response(Topic.AI_VECTORS_QUERY, request_handler, publisher)
    
    # Keep the application running
    try:
        print("Service running. Press Ctrl+C to exit.")
        while True:
            await asyncio.sleep(1)
    except KeyboardInterrupt:
        # Clean up
        await subscriber.close()
        await publisher.close()

if __name__ == "__main__":
    asyncio.run(main())

Configuration Options

The NatsConfig class allows you to customize your NATS connection:

Parameter	Description	Default
server	NATS server address	Required
max_reconnect_attempts	Maximum reconnection attempts	10
reconnect_time_wait	Time between reconnection attempts (seconds)	2
connection_timeout	Connection timeout (seconds)	2
ping_interval	Interval for ping frames (seconds)	20
max_outstanding_pings	Maximum unanswered pings before disconnect	5
max_payload	Maximum size of the payload in bytes	1048576 (1MB)

API Reference

Exported Classes

The following classes are exported directly from the package:

• NatsConfig - Configuration for the NATS connection
• HaiMessage - Message structure for HAI communication
• NatsPublisherAdapter - Adapter for publishing messages
• NatsSubscriberAdapter - Adapter for subscribing to messages
• MessageProcessor - Processing incoming messages
• NatsClientRepository - Low-level NATS client operations
• Topic - Enumeration of predefined topic strings

HaiMessage Structure

The HaiMessage class is the core data structure used for all messaging:

class HaiMessage:
    message_id: str       # Unique identifier for the message
    sender: str           # Identifier of the sender
    topic: str            # The topic or channel for the message
    payload: dict         # Actual message data
    correlation_id: str = None  # Optional reference to a related message
    timestamp: float = None     # Optional message creation timestamp

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

License

This project is licensed under the MIT License - see the LICENSE file for details.