configurationService.afterPropertiesSet();
List<SSEvent> events = ControllerUtil.performSseRequest(mockMvc, "sseProvider",
"message3", null, null, null);
assertThat(events).hasSize(1);
SSEvent event = events.get(0);
assertThat(event.getEvent()).isEqualTo("error");
assertThat(event.getComment()).startsWith(
"java.lang.IllegalStateException: Missing parameter 'id' of type [int]");
assertThat(event.getData()).isEqualTo("Server Error");
assertThat(event.getId()).isNull();
assertThat(event.getRetry()).isNull();
}