How to Build a Realtime Chat Application in Django?

Summary: In this tutorial, you will learn to build a real time chat application using the Django web framework.

To build a realtime chat application in Django, you will need to use websockets to handle the realtime communication between the client and the server.

Here is a high-level overview of the steps you will need to follow:

1. Set up a Django project and app: Create a new Django project and app using the django-admin startproject and python manage.py startapp commands.
2. Install Django Channels: Django Channels is a library that allows Django to support websockets and other asynchronous protocols. Install it using pip install channels.
3. Set up the Django Channels routing: You will need to specify the routing for your websocket connections in the Django Channels routing configuration.
4. Implement the websocket consumer: The websocket consumer is a Django Channels component that handles the websocket connection and communication. You will need to write a consumer class to handle the websocket communication for your chat application.
5. Set up the frontend: You will need to create the HTML, JavaScript, and CSS for the chat application’s frontend. You can use a frontend framework like React or Angular to make this easier.
6. Connect the frontend and backend: Use JavaScript to connect the frontend to the backend websocket consumer and send and receive messages in realtime.

Here is code for each step of building a realtime chat application in Django using Django Channels:

1. Set up a Django project and app:

# Create a new Django project
django-admin startproject project_name

# Navigate to the project directory and create a new Django app
cd project_name
python manage.py startapp app_name

2. Install Django Channels and set up the ASGI application:

# Install Django Channels
pip install channels

# Add "channels" to the INSTALLED_APPS list in settings.py
INSTALLED_APPS = [
    ...
    "channels",
]

# Set the ASGI application to "project_name.routing.application" in settings.py
ASGI_APPLICATION = "project_name.routing.application"

3. Set up the Django Channels routing:

# Create a file called routing.py in your Django app directory
# Define a Django Channels routing configuration in routing.py

from django.urls import path

from . import consumers

websocket_urlpatterns = [
    path("ws/chat/", consumers.ChatConsumer.as_asgi()),
]

4. Implement the websocket consumer:

# Create a file called consumers.py in your Django app directory
# Define a Django Channels consumer class in consumers.py

from channels.generic.websocket import WebsocketConsumer

class ChatConsumer(WebsocketConsumer):
    def connect(self):
        self.accept()

    def disconnect(self, close_code):
        pass

    def receive(self, text_data):
        self.send(text_data=text_data)

The connect method is called when the websocket is handshaking. You can use this method to authenticate the user and perform any other necessary setup.

The disconnect method is called when the websocket connection is closed. You can use this method to clean up any resources that were allocated during the connection.

The receive method is called when the server receives a message from the websocket. You can use this method to process the message and send a response back to the client if necessary.

5. Set up the frontend:

Create an HTML template for the chat application’s frontend. You can use a frontend framework like React or Angular to make this easier.

<!-- Create an HTML template for the chat application's frontend -->
<form id="message-form">
  <input id="message-input" type="text" placeholder="Enter a message">
  <button type="submit">Send</button>
</form>
<div id="messages">
  <!-- Messages will be displayed here -->
</div>

<!-- Include a JavaScript file to handle the websocket communication and message display -->
<script src="/static/js/chat.js"></script>

6. Connect the frontend and backend:

Use JavaScript to establish a websocket connection to the Django Channels consumer. Send and receive messages over the websocket connection using the send and onmessage methods of the WebSocket object.

// In the JavaScript file, establish a websocket connection to the Django Channels consumer
const socket = new WebSocket("ws://localhost:8000/ws/chat/");

// Send a message over the websocket connection
form.addEventListener("submit", (event) => {
  event.preventDefault();
  socket.send(input.value);
  input.value = "";
});

// Update the message display when a new message is received
socket.onmessage = (event) => {
  const message = document.createElement("div");
  message.innerText = event.data;
  messages.appendChild(message);
};

That’s all you need to do to create a Realtime chat application in Django using Django Channels