w.Header().Get(xhttp.AmzRequestID), w.Header().Get(xhttp.AmzRequestHostID))
	encodedErrorResponse := encodeResponse(errorResponse)
	writeResponse(w, err.HTTPStatusCode, encodedErrorResponse, mimeXML)
}

func writeErrorResponseHeadersOnly(w http.ResponseWriter, err APIError) {
	w.Header().Set(xMinIOErrCodeHeader, err.Code)
	w.Header().Set(xMinIOErrDescHeader, "\""+err.Description+"\"")

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

/// tip | "Tipp"

Beachten Sie, dass benutzerdefinierte proprietäre Header hinzugefügt werden können. <a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers" class="external-link" target="_blank">Verwenden Sie dafür das Präfix 'X-'</a>.

        length = 0,
        type = TYPE_SETTINGS,
        flags = FLAG_ACK,
      )
      sink.flush()
    }
  }

  /**
   * HTTP/2 only. Send a push promise header block.
   *
   * A push promise contains all the headers that pertain to a server-initiated request, and a
   * `promisedStreamId` to which response frames will be delivered. Push promise frames are sent as

* `content` – Ein `str` oder `bytes`.
* `status_code` – Ein `int`-HTTP-Statuscode.
* `headers` – Ein `dict` von Strings.
* `media_type` – Ein `str`, der den Medientyp angibt. Z. B. `"text/html"`.

FastAPI (eigentlich Starlette) fügt automatisch einen Content-Length-Header ein. Außerdem wird es einen Content-Type-Header einfügen, der auf dem media_type basiert, und für Texttypen einen Zeichensatz (charset) anfügen.

          if (streamId % 2 == nextStreamId % 2) return

          // Create a stream.
          val headers = headerBlock.toHeaders()
          val newStream = Http2Stream(streamId, this@Http2Connection, false, inFinished, headers)
          lastGoodStreamId = streamId
          streams[streamId] = newStream

    if current_user is None:
        return {"msg": "Create an account first"}
    return current_user


client = TestClient(app)


def test_security_api_key():
    response = client.get("/users/me", headers={"key": "secret"})
    assert response.status_code == 200, response.text
    assert response.json() == {"username": "secret"}


def test_security_api_key_no_key():
    response = client.get("/users/me")

        .build()
    val request =
      originalRequest.newBuilder()
        .header("Upgrade", "websocket")
        .header("Connection", "Upgrade")
        .header("Sec-WebSocket-Key", key)
        .header("Sec-WebSocket-Version", "13")
        .header("Sec-WebSocket-Extensions", "permessage-deflate")
        .build()
    call = RealCall(webSocketClient, request, forWebSocket = true)
    call!!.enqueue(

// For forward compatibility, users that retrieve a Header from Reader.Next,
// mutate it in some ways, and then pass it back to Writer.WriteHeader
// should do so by creating a new Header and copying the fields
// that they are interested in preserving.
type Header struct {
	// Typeflag is the type of header entry.
	// The zero value is automatically promoted to either TypeReg or TypeDir
	// depending on the presence of a trailing slash in Name.

  /** Identifies which member in the ASN.1 schema the field holds. */
  var tag: Long,
  /**
   * If the constructed bit is set it indicates that the value is composed of other values that have
   * their own headers.
   *
   * This value is encoded in bit 6 of the first byte of each value.
   *
   * ```
   * 0bxx0xxxxx Primitive
   * 0bxx1xxxxx Constructed
   * ```
   */
  var constructed: Boolean,

///

Zuerst erstellen wir eine `GzipRequest`-Klasse, welche die Methode `Request.body()` überschreibt, um den Body bei Vorhandensein eines entsprechenden Headers zu dekomprimieren.

Wenn der Header kein `gzip` enthält, wird nicht versucht, den Body zu dekomprimieren.

Auf diese Weise kann dieselbe Routenklasse gzip-komprimierte oder unkomprimierte Requests verarbeiten.

```Python hl_lines="8-15"