Grails应用http.server.requests指标数据采集问题排查及解决

问题

遇到的问题：同一个应用，Spring Boot(Java)和Grails(Groovy)混合编程，常规的Spring Controller，可通过Micromete + Pushgateway，

采集到http.server.requests指标数据，注意下面的指标名称是点号（请忽略下面截图里的接口的uri并不是上面的截图里的）

在Prometheus页面，会发现指标名称已经变成下划线命名，且增加后缀_seconds_sum

为啥Grails的UrlMappings和controller，无法采集到http_server_requests指标数据？（请忽略下面的截图是另一个应用）

源码分析

一开始，我只知道MeterRegistry.registerMeterIfNecessary方法，打个断点，调试可进入断点：

截图如上，tag里的uri全部变成root，也就是上面截图4中看到的所有接口全变成root，不同的是method方法。

为啥会变成root呢？

只能断点调试。

断点调试的前提是熟悉框架代码。想一想，如果不知道方法调用层级关系，怎么打断点呢？

如何熟悉代码？花时间。或者反复询问ChatGPT、DeepSeek、GitHub Copilot。

总之，这里直接给出原因。

WebMvcMetricsFilter类相关方法如下：

@Override
protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain)
		throws ServletException, IOException {
   
	TimingContext timingContext = TimingContext.get(request);
	if (timingContext == null) {
   
		timingContext = startAndAttachTimingContext(request);
	}
	try {
   
		filterChain.doFilter(request, response);
		if (!request.isAsyncStarted()) {
   
			// Only record when async processing has finished or never been started.
			// If async was started by something further down the chain we wait until the second filter invocation (but we'll be using the TimingContext that was attached to the first)
			Throwable exception = fetchException(request);
			record(timingContext, request, response, exception);
		}
	} catch (Exception ex) {
   
		response.setStatus(HttpStatus.INTERNAL_SERVER_ERROR.value());
		record(timingContext, request, response, unwrapNestedServletException(ex));
		throw ex;
	}
}

private void record(TimingContext timingContext, HttpServletRequest request, HttpServletResponse response,
		Throwable exception) {
   
	try {
   
		Object handler = getHandler(request);
		Set<Timed> annotations = getTimedAnnotations(handler);
		Timer.Sample timerSample = timingContext.getTimerSample();
		AutoTimer.apply(this.autoTimer, this.metricName, annotations,
				(builder) -> timerSample.stop(getTimer(builder, handler, request, response, exception)));
	}
	catch (Exception ex) {
   
		logger.warn("Failed to record timer metrics", ex);