Lomond

Warnings

• breaking The library's last release was in 2018 with explicit Python 3.7 compatibility. It is unlikely to be compatible with newer Python versions (3.8+ onwards, especially 3.12) due to significant changes and deprecations in the Python language and standard library over the years (e.g., removal of `distutils`, changes to Unicode handling). Users attempting to run Lomond on modern Python versions may encounter `ImportError` or other runtime errors.
  Fix: Consider using alternative, actively maintained WebSocket client libraries for Python (e.g., `websockets`, `websocket-client`) that are tested and compatible with modern Python versions. If you must use Lomond, restrict your environment to Python 3.7 or earlier, but be aware of the security implications of using an End-of-Life Python version.
• gotcha Lomond is an abandoned library. There are no indications of ongoing maintenance, bug fixes, or security updates. Using an unmaintained library can introduce security vulnerabilities and compatibility issues with other modern packages or operating systems.
  Fix: For new projects, strongly consider using an actively maintained WebSocket client library. For existing projects using Lomond, assess the risks, consider migrating to a current library, or be prepared to maintain any necessary fixes internally.
• gotcha Unhandled exceptions within the event loop will cause Lomond to disconnect the socket without performing a graceful WebSocket closing handshake. This can lead to unexpected client or server state.
  Fix: Always wrap your event handling logic in `try...except` blocks within the `for event in websocket:` loop to catch and handle exceptions gracefully, ensuring explicit `websocket.close()` calls if necessary.
• gotcha While Lomond's `WebSocket` objects are explicitly stated as thread-safe, the library itself does not launch any threads for its core operation. If your application requires concurrent processing beyond simple event handling, you will need to manage threading yourself (e.g., running the WebSocket loop in a separate thread).
  Fix: If your application needs to perform long-running tasks or concurrent I/O alongside WebSocket communication, encapsulate the Lomond event loop within its own dedicated thread to prevent blocking the main application thread.

Install

• pip install lomond Install latest version
• pip install wsaccel Install optional C optimizations

Imports

• WebSocket

  from lomond import WebSocket

  While 'from lomond.websocket import WebSocket' also works, the official quickstart and many examples use 'from lomond import WebSocket' for brevity and consistency.

Quickstart

This example demonstrates how to establish a WebSocket connection using Lomond, send a text message, and print received text messages. Lomond provides an event-driven loop where different `event.name` values indicate connection status or received data. The loop will terminate upon disconnection or explicit `break`.

import os
from lomond import WebSocket

# Using a public echo server for demonstration.
# Replace with your actual WebSocket URL.
websocket = WebSocket(os.environ.get('LOMOND_WS_URL', 'wss://echo.websocket.org'))

print(f"Connecting to {websocket.url}...")

for event in websocket:
    if event.name == 'ready':
        print('WebSocket connection established. Sending a message...')
        websocket.send_text('Hello from Lomond!')
    elif event.name == 'text':
        print(f'Received: {event.text}')
        # Optionally close after receiving a message
        websocket.close()
        break
    elif event.name == 'disconnected':
        print(f'Disconnected: {event.reason}')
        break
    else:
        # Other events like 'connecting', 'connected', 'poll', 'closing' might occur.
        # print(f'Event: {event.name}')
        pass