[Hawkular-dev] Application metrics from Jaeger clients

Hi Metrics Experts! Re: https://github.com/uber/jaeger-client-java/issues/172#issuecomment-299723621 This issue is concerned with supporting Prometheus endpoints within the Jaeger instrumented client applications, to capture Jaeger related metrics (e.g. number of spans reported/sampled/dropped, etc) but also application metrics - i.e. number of requests, errors and latency(duration) for different services/operations (endpoints). As we will be interested in capturing and analysing these metrics within Hawkular Metrics, would be good if someone with relevant experience could get involved in the discussion to ensure the metrics are reported in the most appropriate way. For example - is it a good idea to have generic metrics names (jaeger-rpc.requests - which I assume is a counter, and jaeger-rpc.latency), or a metric name per endpoint - e.g. I was thinking service.operation.direction? Based on the referenced comment, I'm not sure how the tags would relate to the metric names - I thought the tags needed to be constant for a particular metric name, but it might be my misunderstanding of what they are proposing. Would be good to discuss - possibly here first and then when better understood make a proposal on the github issue. Regards Gary