También puede ayudar a evitar confusiones para nuevos desarrolladores que vean un parámetro no usado en tu código y puedan pensar que es innecesario.

///

/// info | Información

En este ejemplo usamos headers personalizados inventados `X-Key` y `X-Token`.

        .url("https://publicobject.com/helloworld.txt")
        .build();

    try (Response response = client.newCall(request).execute()) {
      if (!response.isSuccessful()) {
        Headers responseHeaders = response.headers();
        for (int i = 0; i < responseHeaders.size(); i++) {
          System.out.println(responseHeaders.name(i) + ": " + responseHeaders.value(i));
        }

        server minio3:9001;
        server minio4:9001;
    }

    server {
        listen       9000;
        listen  [::]:9000;
        server_name  localhost;

        # To allow special characters in headers
        ignore_invalid_headers off;
        # Allow any size file to be uploaded.
        # Set to a value such as 1000m; to restrict file size to a specific value
        client_max_body_size 0;

    }

    /**
     * Checks if `expected` and `observed` are equal when viewed as a set and headers are
     * deduped.
     *
     * TODO: See if duped headers should be preserved on decode and verify.
     */
    private fun assertSetEquals(
      message: String,
      expected: List<Header>,
      observed: List<Header>,
    ) {
      assertThat(LinkedHashSet(observed), message)
        .isEqualTo(LinkedHashSet(expected))

        server minio3:9001;
        server minio4:9001;
    }

    server {
        listen       9000;
        listen  [::]:9000;
        server_name  localhost;

        # To allow special characters in headers
        ignore_invalid_headers off;
        # Allow any size file to be uploaded.
        # Set to a value such as 1000m; to restrict file size to a specific value
        client_max_body_size 0;

  data?.let {
    request.method(requestMethod, it.toRequestBody(mediaType()))
  }

  for (header in headers.orEmpty()) {
    val parts = header.split(':', limit = 2)
    if (!isSpecialHeader(parts[0])) {
      request.header(parts[0], parts[1])
    }
  }
  referer?.let {
    request.header("Referer", it)
  }
  request.header("User-Agent", userAgent)

  return request.build()
}

        server minio3:9001;
        server minio4:9001;
    }

    server {
        listen       9000;
        listen  [::]:9000;
        server_name  localhost;

        # To allow special characters in headers
        ignore_invalid_headers off;
        # Allow any size file to be uploaded.
        # Set to a value such as 1000m; to restrict file size to a specific value
        client_max_body_size 0;

      }
      dataStream.receiveData(source, length)
      if (inFinished) {
        dataStream.receiveHeaders(Headers.EMPTY, true)
      }
    }

    override fun headers(
      inFinished: Boolean,
      streamId: Int,
      associatedStreamId: Int,
      headerBlock: List<Header>,
    ) {
      if (pushedStream(streamId)) {
        pushHeadersLater(streamId, headerBlock, inFinished)
        return

But for security, as the server doesn't know it is behind a trusted proxy, it won't interpret those headers.

/// note | Technical Details

The proxy headers are:

* <a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Reference/Headers/X-Forwarded-For" class="external-link" target="_blank">X-Forwarded-For</a>

		# Write object back to S3 Object Lambda
		# response sends the transformed data
		# back to MinIO and then to the user
		resp = make_response(transformed_object, 200)
		resp.headers['x-amz-request-route'] = request_route
		resp.headers['x-amz-request-token'] = request_token
		return resp

	else:
		abort(400)

if __name__ == '__main__':
	app.run()
```