```Python hl_lines="8-9  11  14"
{!../../docs_src/middleware/tutorial001.py!}
```

/// tip

Keep in mind that custom proprietary headers can be added <a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers" class="external-link" target="_blank">using the 'X-' prefix</a>.

Ce qui est incroyablement utile au moment de développer et débugger du code qui interagit avec votre API.

///

## Documentation

Et quand vous vous rendez sur <a href="http://127.0.0.1:8000/docs" class="external-link" target="_blank">http://127.0.0.1:8000/docs</a>, vous verrez la
documentation générée automatiquement et interactive :

<img src="/img/tutorial/path-params/image01.png">

/// info

///

/// note | "Technical Details"

Any function that is valid to use with:

* <a href="https://docs.python.org/3/library/contextlib.html#contextlib.contextmanager" class="external-link" target="_blank">`@contextlib.contextmanager`</a> or
* <a href="https://docs.python.org/3/library/contextlib.html#contextlib.asynccontextmanager" class="external-link" target="_blank">`@contextlib.asynccontextmanager`</a>

///

## OpenAPI and API docs

If you return additional status codes and responses directly, they won't be included in the OpenAPI schema (the API docs), because FastAPI doesn't have a way to know beforehand what you are going to return.

      when (val protocol = sslSocket.applicationProtocol) {
        null, "" -> null
        else -> protocol
      }
    } catch (e: UnsupportedOperationException) {
      // https://docs.oracle.com/javase/9/docs/api/javax/net/ssl/SSLSocket.html#getApplicationProtocol--
      null
    }
  }

  @SuppressLint("NewApi")
  override fun configureTlsExtensions(
    sslSocket: SSLSocket,
    hostname: String?,

  /**
   * The HTTP <a
   * href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/X-Forwarded-Host">{@code
   * X-Forwarded-Host}</a> header field name.
   *
   * @since 20.0
   */
  public static final String X_FORWARDED_HOST = "X-Forwarded-Host";

  /**
   * The HTTP <a
   * href="https://docs.aws.amazon.com/elasticloadbalancing/latest/classic/x-forwarded-headers.html#x-forwarded-port">{@code

* Sie können Metadaten aus der hochgeladenen Datei auslesen.
* Es hat eine <abbr title="dateiartig"><a href="https://docs.python.org/3/glossary.html#term-file-like-object" class="external-link" target="_blank">file-like</a></abbr> `async`hrone Schnittstelle.

* Você pode obter metadados do arquivo enviado.
* Ela possui uma interface <a href="https://docs.python.org/3/glossary.html#term-file-like-object" class="external-link" target="_blank">semelhante a arquivos</a> `async`.

	Tag      string `json:"tag,omitempty"`
}

// NsInfo represents namespace related information like pods running there.
// It is used to display data and is exposed for integration tests.
type NsInfo struct {
	Name string             `json:"name,omitempty"`
	Pods []*PodFilteredInfo `json:"pods,omitempty"`
}

// RevisionDescription is used to display revision related information.

        }
        if (buf.indexOf("yy") == -1) {
            final int pos = buf.indexOf("y");
            if (pos != -1) {
                buf.replace(pos, pos + 1, "yy");
            }
        }
        if (buf.indexOf("MM") == -1) {
            final int pos = buf.indexOf("M");
            if (pos != -1) {
                buf.replace(pos, pos + 1, "MM");
            }
        }
        if (buf.indexOf("dd") == -1) {