title: WebSockets API
description: "API reference for WebSocket support in JustAPI, the FastAPI alternative — handler registration and connection management."
keywords: [websockets, fastapi alternative, justapi, websocket handler, real-time, bidirectional]
@app.websocket()
Register a WebSocket handler:
@app.websocket(path="/ws")
async def handler(ws):
await ws.accept()
...
| Parameter |
Type |
Default |
Description |
path |
str |
required |
WebSocket endpoint path |
WebSocket Object
| Method |
Description |
await ws.accept() |
Accept the WebSocket upgrade |
await ws.receive_text() |
Receive a text message (str) |
await ws.receive_bytes() |
Receive a binary message (bytes) |
await ws.receive_json() |
Receive and parse JSON message |
await ws.send_text(data) |
Send a text message |
await ws.send_bytes(data) |
Send a binary message |
await ws.send_json(data) |
Send JSON message |
await ws.close() |
Close the connection |
WebSocketState
| State |
Description |
CONNECTING |
Initial state, waiting for upgrade |
OPEN |
Connection established, messages can be exchanged |
CLOSING |
Close frame sent/received |
CLOSED |
Connection closed |
Example
@app.websocket("/chat")
async def chat(ws):
await ws.accept()
try:
while True:
msg = await ws.receive_text()
await ws.send_text(f"Echo: {msg}")
except Exception:
pass
finally:
await ws.close()
See Also