channels-sqlite 0.1

Sqlite3 Based Channel Layer

channels-sqlite is a Django app providing a channels layer backed by SQLite. It uses a dedicated SQLite3 database for asynchronous message handling, making it lightweight and easy to set up without Redis or other external services.

1. Add the app to INSTALLED_APPS

INSTALLED_APPS = [
    # other apps
    "channels",
    "channels_sqlite",
]

2. Configure databases

You need two SQLite databases: one for your main Django data (default), and one dedicated to Channels (channels).

DATABASES = {
    "default": {
        "ENGINE": "django.db.backends.sqlite3",
        "NAME": BASE_DIR / "db.sqlite3",
    },
    "channels": {
        "ENGINE": "django.db.backends.sqlite3",
        "NAME": BASE_DIR / "channels.sqlite3",
        "init_command": "PRAGMA journal_mode=WAL;",
        "transaction_mode": "IMMEDIATE",
        "OPTIONS": {
            "timeout": 20,
            "init_command": """
                PRAGMA journal_mode=WAL;
                PRAGMA synchronous=NORMAL;
                PRAGMA busy_timeout=20000;
                PRAGMA cache_size=-64000;
                PRAGMA temp_store=MEMORY;
                PRAGMA mmap_size=134217728;
            """,
        },
    },
}

Note

WAL mode (Write-Ahead Logging) ensures that multiple readers and a writer can operate concurrently without blocking each other, improving performance for polling-heavy workloads.

3. Configure the channel layer

CHANNEL_LAYERS = {
    "default": {
        "BACKEND": "channels_sqlite.layers.SqliteChannelLayer",
        "CONFIG": {
            "database": "channels",        # must match database alias
            "polling_interval": 0.05,      # Poll every 50ms
            "message_retention": 86400,    # Keep messages for 1 day
            "capacity": 100,               # Max messages per consumer queue
            "expiry": 30,                  # Message TTL in seconds
            "trim_batch_size": 100,        # Cleanup batch size
            "auto_trim": True,             # Auto cleanup old messages
        },
    },
}

4. Add database router

DATABASE_ROUTERS = [
    "channels_sqlite.db_routers.ChannelsRouter",
]

This ensures that migrations for channels_sqlite go into the dedicated channels database.

5. Apply migrations

Run migrations for both databases:

# Default Django models
python manage.py migrate

# Channels-specific tables
python manage.py migrate --database=channels

6. Start the development server

python manage.py runserver

Your channel layer is now configured. Django Channels will handle WebSocket and background task messages asynchronously using the lightweight SQLite channels database.

Example Project

This repository also contains an example/ Django project that demonstrates how to use channels-sqlite in practice.

To run the example:

cd example
uv sync
python manage.py migrate
python manage.py migrate --database=channels
python manage.py runserver

Then open http://127.0.0.1:8000/chat in your browser to test it.

channels-sqlite provides a simple, dependency-free way to get started with Django Channels, perfect for development and lightweight deployments.