@Test
public void clientError() {

    startTestSearchSource(null, null);
    sinkProbe.request(1L);
    conciergeForwarderProbe.expectMsg(streamThings(null));
    conciergeForwarderProbe.reply(InvalidRqlExpressionException.newBuilder().build());
    assertThat(sinkProbe.expectError()).isInstanceOf(InvalidRqlExpressionException.class);
}