*   int result = 1;
 *   while ((response = response.priorResponse()) != null) {
 *     result++;
 *   }
 *   return result;
 * }
 * ```
 *
 * [1]: https://tools.ietf.org/html/rfc2817
 */
fun interface Authenticator {
  /**
   * Returns a request that includes a credential to satisfy an authentication challenge in
   * [response]. Returns null if the challenge cannot be satisfied.
   *

{* ../../docs_src/websockets/tutorial002.py hl[66:77,76:91] *}

/// info

👉 *️⃣ ⚫️ 🚫 🤙 ⚒ 🔑 🤚 `HTTPException`, ↩️ 👥 🤚 `WebSocketException`.

👆 💪 ⚙️ 📪 📟 ⚪️➡️ <a href="https://tools.ietf.org/html/rfc6455#section-7.4.1" class="external-link" target="_blank">☑ 📟 🔬 🔧</a>.

///

### 🔄 *️⃣ ⏮️ 🔗

🚥 👆 📁 📛 `main.py`, 🏃 👆 🈸 ⏮️:

<div class="termy">

```console

Starlette и **FastAPI** основаны на <a href="https://anyio.readthedocs.io/en/stable/" class="external-link" target="_blank">AnyIO</a>, которая делает их совместимыми как с <a href="https://docs.python.org/3/library/asyncio-task.html" class="external-link" target="_blank">asyncio</a> - стандартной библиотекой Python, так и с <a href="https://trio.readthedocs.io/en/stable/" class="external-link" target="_blank">Trio</a>.

The TLS versions and cipher suites in each spec can change with each release. For example, in OkHttp 2.2 we dropped support for SSL 3.0 in response to the [POODLE](https://googleonlinesecurity.blogspot.ca/2014/10/this-poodle-bites-exploiting-ssl-30.html) attack. And in OkHttp 2.3 we dropped support for [RC4](https://en.wikipedia.org/wiki/RC4#Security). As with your desktop web browser, staying up-to-date with OkHttp is the best way to stay secure.

			// handle otherwise we would see a signature mismatch.
			// `aws-cli` sets this as part of signed headers.
			//
			// According to
			// http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.20
			// Expect header is always of form:
			//
			//   Expect       =  "Expect" ":" 1#expectation
			//   expectation  =  "100-continue" | expectation-extension
			//

  public void run() throws Exception {
    Map<String, String> requestBody = new LinkedHashMap<>();
    requestBody.put("longUrl", "https://publicobject.com/2014/12/04/html-formatting-javadocs/");
    RequestBody jsonRequestBody = RequestBody.create(
        mapJsonAdapter.toJson(requestBody), MEDIA_TYPE_JSON);
    Request request = new Request.Builder()

Form gövdelerini tanımlamak için `Form` sınıfını kullanmanız gerekir; çünkü bu olmadan parametreler sorgu parametreleri veya gövde (JSON) parametreleri olarak yorumlanır.

///

## "Form Alanları" Hakkında

HTML formlarının (`<form></form>`) verileri sunucuya gönderirken JSON'dan farklı özel bir kodlama kullanır.

**FastAPI** bu verilerin JSON yerine doğru şekilde okunmasını sağlayacaktır.

/// note | Teknik Detaylar

Ainsi, la ligne :

```Python
    uvicorn.run(app, host="0.0.0.0", port=8000)
```

ne sera pas exécutée.

/// info

Pour plus d'informations, consultez <a href="https://docs.python.org/3/library/__main__.html" class="external-link" target="_blank">la documentation officielle de Python</a>.

///

## Exécutez votre code avec votre <abbr title="En anglais: debugger">débogueur</abbr>

     *
     * [alt_svc]: http://tools.ietf.org/html/draft-ietf-httpbis-alt-svc-01
     *
     * @param streamId when a client-initiated stream ID (odd number), the origin of this alternate
     *     service is the origin of the stream. When zero, the origin is specified in the `origin`
     *     parameter.
     * @param origin when present, the [origin](http://tools.ietf.org/html/rfc6454) is typically

```Python hl_lines="3"
import os

name = os.getenv("MY_NAME", "World")
print(f"Hello {name} from Python")
```

/// tip | Tipp

Das zweite Argument für <a href="https://docs.python.org/3.8/library/os.html#os.getenv" class="external-link" target="_blank">`os.getenv()`</a> ist der zurückzugebende Defaultwert.

Wenn nicht angegeben, ist er standardmäßig `None`. Hier übergeben wir `"World"` als Defaultwert.

///