Channels — Real-Time Communication

Django Channels brings WebSocket support to Django, and Pytigon wraps it with a clean, convention-based interface. Define consumers, connect to rooms, and push real-time updates — all without leaving the Pytigon ecosystem.

Consumer Definition

Create a file consumers.py in your application directory. Pytigon auto-discovers it:

# [app_name]/consumers.py
from pytigon_lib.schdjangoext.channels_utils import PtigJsonWebsocketConsumer

class MyConsumer(PtigJsonWebsocketConsumer):
    def connect(self):
        # Called when a WebSocket connection is established
        self.room_group_name = "my_room"
        self.accept()

    def receive_json(self, content):
        # Called when JSON data arrives from the client
        action = content.get("action")
        if action == "ping":
            self.send_json({"action": "pong"})

    def table_update(self, event):
        # Called when a table update event is received
        self.send_json(event["data"])

Room-Based Messaging

Use Django Channels' layer system to broadcast to groups:

from channels.layers import get_channel_layer
from asgiref.sync import async_to_sync

def notify_table_change(table_name, record_id):
    channel_layer = get_channel_layer()
    async_to_sync(channel_layer.group_send)(
        f"table_{table_name}",
        {
            "type": "table_update",
            "data": {"table": table_name, "id": record_id}
        }
    )

Client-Side Integration

The Pytigon JavaScript library automatically handles WebSocket connections:

// Connection is established automatically
// Listen for server-sent events
ptig.socket.on('table_update', function(data) {
    if (data.table === 'MyTable') {
        ptig.table.refresh();
    }
});

// Send data to server
ptig.socket.send({
    action: 'subscribe',
    table: 'MyTable',
    filter: 'active'
});

Use Cases

  • Live table updates — When one user edits a record, all users see the change
  • Notification system — Push alerts to specific users or groups
  • Chat/messaging — Real-time communication between users
  • Progress tracking — Show task progress bars updating in real-time
  • Collaborative editing — Multiple users editing the same form simultaneously

Channel Layer Configuration

In production, configure Redis as the channel layer backend:

# settings_app.py
CHANNEL_LAYERS = {
    "default": {
        "BACKEND": "channels_redis.core.RedisChannelLayer",
        "CONFIG": {
            "hosts": [("127.0.0.1", 6379)],
        },
    },
}

For development, the in-memory layer works without any external dependencies.

?: Channels ?: Channels