text-align: center;
}

.user .count {
  font-size: 80%;
  text-align: center;
}

a.announce-link:link,
a.announce-link:visited {
  color: #fff;
}

a.announce-link:hover {
  color: var(--md-accent-fg-color);
}

.announce-wrapper {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  align-items: center;
}

.announce-wrapper div.item {
  display: none;
}

  custom_dir: ../en/overrides
  palette:
  - media: '(prefers-color-scheme: light)'
    scheme: default
    primary: teal
    accent: amber
    toggle:
      icon: material/lightbulb
      name: Switch to dark mode
  - media: '(prefers-color-scheme: dark)'
    scheme: slate
    primary: teal
    accent: amber
    toggle:
      icon: material/lightbulb-outline
      name: Switch to light mode
  features:
  - search.suggest

app = FastAPI()


@app.websocket_route("/")
async def index(websocket: WebSocket):
    await websocket.accept()
    await websocket.send_text("Hello, world!")
    await websocket.close()


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


@prefix_router.websocket_route("/")

@app.get("/large")
async def large():
    return PlainTextResponse("x" * 4000, status_code=200)


client = TestClient(app)


def test_middleware():
    response = client.get("/large", headers={"accept-encoding": "gzip"})
    assert response.status_code == 200, response.text
    assert response.text == "x" * 4000
    assert response.headers["Content-Encoding"] == "gzip"
    assert int(response.headers["Content-Length"]) < 4000

            - cookies
            - client
            - state
            - url_for
            - client_state
            - application_state
            - receive
            - send
            - accept
            - receive_text
            - receive_bytes
            - receive_json
            - iter_text
            - iter_bytes
            - iter_json
            - send_text
            - send_bytes

As Python advances, **newer versions** come with improved support for these type annotations and in many cases you won't even need to import and use the `typing` module to declare the type annotations.

If you can choose a more recent version of Python for your project, you will be able to take advantage of that extra simplicity.

In all the docs there are examples compatible with each version of Python (when there's a difference).

* Fix incorrect `Request` class import. PR [#493](https://github.com/tiangolo/fastapi/pull/493) by [@kamalgill](https://github.com/kamalgill).

## 0.38.0

* Add recent articles to [External Links](https://fastapi.tiangolo.com/external-links/) and recent opinions. PR [#490](https://github.com/tiangolo/fastapi/pull/490).

@app.websocket("/items/{item_id}/ws")
async def websocket_endpoint(
    websocket: WebSocket,
    item_id: str,
    q: int | None = None,
    cookie_or_token: str = Depends(get_cookie_or_token),
):
    await websocket.accept()
    while True:
        data = await websocket.receive_text()
        await websocket.send_text(
            f"Session cookie or query token value is: {cookie_or_token}"
        )
        if q is not None:

Wenn ein eingehender Request nicht korrekt validiert wird, wird eine „400“-Response gesendet.

## `GZipMiddleware`

Verarbeitet GZip-Responses für alle Requests, die `"gzip"` im `Accept-Encoding`-Header enthalten.

Diese Middleware verarbeitet sowohl Standard- als auch Streaming-Responses.

```Python hl_lines="2  6"
{!../../../docs_src/advanced_middleware/tutorial003.py!}
```

* `allowed_hosts` - 📇 🆔 📛 👈 🔜 ✔ 📛. 🃏 🆔 ✅ `*.example.com` 🐕‍🦺 🎀 📁. ✔ 🙆 📛 👯‍♂️ ⚙️ `allowed_hosts=["*"]` ⚖️ 🚫 🛠️.

🚥 📨 📨 🔨 🚫 ✔ ☑ ⤴️ `400` 📨 🔜 📨.

## `GZipMiddleware`

🍵 🗜 📨 🙆 📨 👈 🔌 `"gzip"` `Accept-Encoding` 🎚.

🛠️ 🔜 🍵 👯‍♂️ 🐩 & 🎥 📨.

```Python hl_lines="2  6"
{!../../../docs_src/advanced_middleware/tutorial003.py!}
```

📄 ❌ 🐕‍🦺: