Add support for adding exemplars?

[emschwartz]

Some metrics libraries, such as prometheus-client, support adding OpenMetrics exemplars to counters and histograms. If people are interested in such a feature, we could investigate adding support to the autometrics API for attaching dynamic function parameters as exemplars.

Please 👍 if you would be interested in this.

Suggested by SpudnikV on Reddit.

[emschwartz]

If we add support for prometheus-client (#25), we might want to have another optional feature to use the tracing crate to automatically grab fields like a trace_id or user_id and attach those fields as properties of the exemplars.