The in-use client endpoint metric is incremented when request reset is called.

[dlfcn]

Questions

Why is the in-use counter incremented when a request reset happens?

vertx-dropwizard-metrics/src/main/java/io/vertx/ext/dropwizard/impl/EndpointMetrics.java

Line 45 in 392440f

inUse.inc();

Version

4.5.4

Context

While testing an HTTP service I noticed the in-use client enpoint metric kept increasing and would not return to a zero value when traffic was stopped. Other metrics showed request timeouts were occuring. Looking at the EndpointMetric implementation I saw that the in-use counter is incremented instead of being dercemented. This results in the in-use counter getting incremented twice, one increment when a request is sent, and another inrement when a timeout occurs.

Do you have a reproducer?

https://github.com/dlfcn/in-use-client-endpoint-metric-test/blob/master/src/test/java/InUseClientEndpointMetricTest.java

Steps to reproduce

1. Create Vertx instance with DropwizardMetricsServiceImpl.
2. Create HTTP server that does not send a response.
3. Create WebClient with a MetricsName and Vertx instance and send request to HTTP server.
4. Expect the request sent by the WebClient to timeout.
5. Get metrics snapshot from metrics service and assert in-use value is zero.

Extra

None.