# Testing WebSockets

You can use the same `TestClient` to test WebSockets.

For this, you use the `TestClient` in a `with` statement, connecting to the WebSocket:

```python
from fastapi import FastAPI
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)
    response = client.get("/")
    assert response.status_code == 200
    assert response.json() == {"msg": "Hello World"}


def test_websocket():
    client = TestClient(app)
    with client.websocket_connect("/ws") as websocket:
        data = websocket.receive_json()
        assert data == {"msg": "Hello WebSocket"}
```

:::callout{intent="note"}
For more details, check Starlette's documentation for [testing WebSockets](https://starlette.dev/testclient/#testing-websocket-sessions).
:::

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