@Test
public void rejectValidConnectionWithInvalidNumberSourcePayloadMapping() {

    exception.expect(ConnectionConfigurationInvalidException.class);
    final Connection connection = createConnection(CONNECTION_ID)
            .toBuilder()
            .setSources(TestConstants.Sources.SOURCES_WITH_INVALID_MAPPING_NUMBER)
            .build();
    final ConnectionValidator underTest = getConnectionValidator();
    underTest.validate(connection, DittoHeaders.empty(), actorSystem);
}