Implementing WebSockets in FastAPI

Welcome to implementing WebSockets with FastAPI! WebSockets provide a persistent, full-duplex communication channel between a client and a server.

• Full-duplex: Both client and server can send and receive messages simultaneously.
• Real-time: Ideal for applications needing instant updates, like chat, live dashboards, or gaming.

FastAPI has excellent built-in support for WebSockets, leveraging Python's async/await features.

Just like HTTP endpoints, you define WebSocket endpoints using a decorator. Instead of @app.get() or @app.post(), you use @app.websocket().

Your endpoint function must be async def and accept a websocket: WebSocket parameter. This WebSocket object is your primary tool for interaction.

The first step inside your function is always to await websocket.accept() to establish the connection.