Live Chat ~ Django Channels Quickstart - uchicago-cs/chigame GitHub Wiki

This guide introduces how to use Django Channels to implement real-time live chat using WebSockets. It includes a high-level overview of Django Channels, how WebSockets work, and practical setup instructions for building or maintaining live chat functionality.

What is Django Channels?

Django Channels extends the built-in Django abilities to handle not only HTTP but also protocols that require long-running connections, such as WebSockets, chatbots, IoT, and more. This makes it suitable for building real-time features like chat, notifications, or collaborative tools.

Unlike traditional Django (which uses WSGI and synchronous HTTP requests), Django Channels enables long-lived, bidirectional connections between client and server using ASGI (Asynchronous Server Gateway Interface).

For live chat, this means:

  • Messages can be sent and received instantly, without polling
  • Multiple users can connect to the same room and see messages update in real time
  • The backend can manage group-based broadcasting and user-specific events easily

What are WebSockets?

WebSockets are a communication protocol that provides full-duplex (two-way) communication over a single TCP connection.

In contrast to HTTP polling (which repeatedly asks the server for updates), WebSockets keep a connection open, so the server can push updates to the client as they happen. This is good for chat apps, where users expect messages to appear without delay.

Channel Packages

  • Channels, the Django integration layer
  • Daphne, the HTTP and Websocket termination server
  • asgiref, the base ASGI library
  • channels_redis, the Redis channel layer backend (optional)

Django Channels Setup

1. Install Required Packages

  • Install daphne and channels for ASGI support: pip install daphne pip install channels
  • Add daphne to requirements/base.txt
  • Add channels to requirements/base.txt

2. Create a New App for Chat

  • Create a Django app named chat
  • Register it in INSTALLED_APPS in settings.py

3. Enable ASGI Support

  • Add asgi.py to the project root (alongside settings.py)
  • Update asgi.py to route WebSocket requests via ProtocolTypeRouter and AuthMiddlewareStack

4. Create Routing and Consumer

  • Add chat/routing.py for URL patterns
  • Create a ChatConsumer class in chat/consumers.py

More Resources

  • Official Django Channels Docs (link)
  • TestDriven.io: Django Channels Guide (link)
  • GeeksforGeeks: Django Channels—Introduction and Basic Setup (link)