@router.websocket("/router2")
async def routerindex2(websocket: WebSocket):
    await websocket.accept()
    await websocket.send_text("Hello, router!")
    await websocket.close()


@router.websocket("/router/{pathparam:path}")
async def routerindexparams(websocket: WebSocket, pathparam: str, queryparam: str):
    await websocket.accept()
    await websocket.send_text(pathparam)
    await websocket.send_text(queryparam)

from fastapi.testclient import TestClient
from fastapi.websockets import WebSocket

app = FastAPI()


@app.get("/")
async def read_main():
    return {"msg": "Hello World"}


@app.websocket("/ws")
async def websocket(websocket: WebSocket):
    await websocket.accept()
    await websocket.send_json({"msg": "Hello WebSocket"})
    await websocket.close()


def test_read_main():
    client = TestClient(app)

@app.websocket("/", dependencies=[create_dependency("index")])
async def index(websocket: WebSocket, deps: DepList):
    await websocket.accept()
    await websocket.send_text(json.dumps(deps))
    await websocket.close()


@router.websocket("/router", dependencies=[create_dependency("routerindex")])
async def routerindex(websocket: WebSocket, deps: DepList):
    await websocket.accept()

  @Override public void onMessage(WebSocket webSocket, String text) {
    System.out.println("onMessage: " + text);
  }

  @Override public void onClosing(WebSocket webSocket, int code, String reason) {
    webSocket.close(1000, null);
    System.out.println("onClose (" + code + "): " + reason);
  }

  @Override public void onFailure(WebSocket webSocket, Throwable t, Response response) {

            message = "Message one"
            websocket.send_text(message)
            data = websocket.receive_text()
            assert data == "Session cookie or query token value is: some-token"
            data = websocket.receive_text()
            assert data == f"Message text was: {message}, for item ID: bar"
            message = "Message two"
            websocket.send_text(message)

    client.dispatcher().executorService().shutdown();
  }

  @Override public void onOpen(WebSocket webSocket, Response response) {
    webSocket.send("Hello...");
    webSocket.send("...World!");
    webSocket.send(ByteString.decodeHex("deadbeef"));
    webSocket.close(1000, "Goodbye, World!");
  }

  @Override public void onMessage(WebSocket webSocket, String text) {
    System.out.println("MESSAGE: " + text);
  }

    route: APIWebSocketRoute = websocket.scope["route"]
    await websocket.accept()
    await websocket.send_json({"item_id": item_id, "path": route.path})


client = TestClient(app)


def test_get():
    response = client.get("/users/rick")
    assert response.status_code == 200, response.text
    assert response.json() == {"user_id": "rick", "path": "/users/{user_id}"}

   * messages.
   */
  open fun onOpen(
    webSocket: WebSocket,
    response: Response,
  ) {
  }

  /** Invoked when a text (type `0x1`) message has been received. */
  open fun onMessage(
    webSocket: WebSocket,
    text: String,
  ) {
  }

  /** Invoked when a binary (type `0x2`) message has been received. */
  open fun onMessage(
    webSocket: WebSocket,
    bytes: ByteString,
  ) {
  }

  /**

    </body>
</html>
"""


@app.get("/")
async def get():
    return HTMLResponse(html)


@app.websocket("/ws")
async def websocket_endpoint(websocket: WebSocket):
    await websocket.accept()
    while True:
        data = await websocket.receive_text()

{!../../docs_src/websockets/tutorial001.py!}
```

## Einen `websocket` erstellen

Erstellen Sie in Ihrer **FastAPI**-Anwendung einen `websocket`:

```Python hl_lines="1  46-47"
{!../../docs_src/websockets/tutorial001.py!}
```

/// note | "Technische Details"

Sie können auch `from starlette.websockets import WebSocket` verwenden.