@Test
public void mapToDittoProtocolMessage() {

    final Map<String, String> headers = Map.of(
            "content-type", "application/vnd.eclipse.ditto+json",
            "ditto-message-subject", "hello/world",
            "ditto-message-thing-id", "thing:id"
    );
    final String payload = "{\n" +
            "  \"topic\": \"com.acme/xdk_53/things/twin/commands/delete\",\n" +
            "  \"headers\": {},\n" +
            "  \"path\": \"/\",\n" +
            "  \"status\": 204\n" +
            "}";
    final List<Adaptable> adaptables =
            underTest.map(ExternalMessageFactory.newExternalMessageBuilder(headers)
                    .withText(payload)
                    .build());
    assertThat(adaptables).hasSize(1);
    final Signal<?> signal = ADAPTER.fromAdaptable(adaptables.get(0));
    assertThat(signal).isInstanceOf(DeleteThingResponse.class);
}