hashReader.SetExpectedMax(lengthRange.Max)
		}
	}

	// Extract metadata to be saved from received Form.
	metadata := make(map[string]string)
	err = extractMetadataFromMime(ctx, textproto.MIMEHeader(formValues), metadata)
	if err != nil {
		writeErrorResponse(ctx, w, toAPIError(ctx, err), r.URL)
		return
	}

	rawReader := hashReader