py-pg-notify 1.0.2

Simplifies listening to and sending notifications using PostgreSQL

py-pg-notify

py-pg-notify is a Python library that simplifies listening to and sending notifications using PostgreSQL. This package leverages asyncpg for asynchronous communication with the database, making it ideal for real-time applications.

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📖 Features

• 🔊 PostgreSQL Notifications: Easy-to-use interfaces for PostgreSQL notifications.
• 🔄 Asynchronous: Fully asynchronous with support for multiple listeners and channels.
• 📦 Lightweight: Built on top of asyncpg, offering high performance.
• ⚙️ Custom Handlers: Define your notification handling logic dynamically.

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🚀 Installation

Install the package via pip:

pip install py-pg-notify

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Usage

Configuration Example

You can use PGConfig to manage PostgreSQL connection parameters via a dictionary, environment variables, or direct parameters.

from py_pg_notify import PGConfig

# Example using keyword args
kwargs = {
    "user": "<username>",
    "password": "<password>",
    "host": "<host>",
    "port": 5432,
    "dbname": "<dbname>"
}
config = PGConfig(**kwargs)

# Example using environment variables
# Ensure PG_USER, PG_PASSWORD, PG_HOST, PG_PORT, and PG_DBNAME are set in your environment
config = PGConfig()

# Example using direct parameters
config = PGConfig(user="<username>", password="<password>", host="<host>", port=5432, dbname="<dbname>")

Notifier Example

import asyncio
from py_pg_notify import Notifier, PGConfig

async def create_trigger_example():
    # Define the configuration using environment variables
    config = PGConfig()

    async with Notifier(config) as notifier:

        # Send a custom message to 'ch_01' channel
        await notifier.notify("ch_01", "message")

        # Set up a trigger to notify 'ch_01' when the table is modified
        await notifier.create_trigger_function("notify_function", "ch_01")
        
        await notifier.create_trigger(
            table_name="my_table",
            trigger_name="my_trigger",
            function_name="notify_function",
            event="INSERT",
        )

        trigger_functions = await notifier.get_trigger_functions("my_table")
        print("Existing Trigger Functions:", trigger_functions)

        triggers = await notifier.get_triggers("my_table")
        print("Existing Triggers:", triggers)

        await notifier.remove_trigger("my_table", "my_trigger")

        await notifier.remove_trigger_function("notify_function")

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

Listener Example

import asyncio
from py_pg_notify import Listener, PGConfig, Notification

async def notification_handler(msg: Notification):
    # Perform any processing on the received notification
    print(f"Notification received: Channel={msg.channel}, Payload={msg.payload}")

async def main():
    # Define the configuration using environment variables
    config = PGConfig()

    async with Listener(config) as listener:
        await listener.add_listener("ch_01", notification_handler)
        await asyncio.sleep(3600)  # Simulate long-running process

if __name__ == "__main__":
    try: 
        asyncio.run(main())
    except KeyboardInterrupt:
        exit(0)

Examples

Refer to the examples folder for complete usage scenarios.

1. 📬 PubSub Example - Demonstrates a simple Pub/Sub implementation using py-pg-notify.

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📄 License

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

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🤝 Contributing

We welcome contributions! Please follow these steps:

1. Fork the repository.
2. Create a new branch.
3. Make your changes.
4. Add the test cases if needed.
5. Test all the test cases for verfication.
6. Submit a pull request.

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📢 Feedback and Support

For bugs or feature requests, create an issue in the GitHub repository. We'd love to hear your feedback!