Where are gauges?

[onemenny]

Why are gauges missing from the library?

[tolbertam]

It looks like they are missing, the way I mimic them is using counters, i.e. whenever I go to update the metric:

    connectionCounter.clear();
    connectionCounter.inc(connectionCount);

Although the benefit of gauges is that you can configure when the values are updated, i.e. either on request or cached. I think it'd be a good idea to add support.

[mikejihbe]

You're right, they're missing. Would definitely accept a PR.

[tolbertam]

I'd be happy to give this a shot as I have a few metrics that are counters that should probably be gauges. I'll follow the dropwizard metrics library and provide implementations to match those (docs), except JMX gauges of course 😉

[rafalsiwiec]

Hey @tolbertam, is this going to happen in the nearest future? :)
If not, then I'm keen to prepare the PR.

[tolbertam]

Hi @rafalsiwiec , this kind of slid off my radar and i won't have time to do this in the near future,so I would definitely appreciate a PR, thanks!

[rafalsiwiec]

@tolbertam with this PR #59, I would like to start a discussion: what else gauges do we want to have?

• CachedGauge - with configurable expiration period seems ok
• RatioGauge and Derivative Gauges - I don't think they're actually needed

Also, I think that some utility for projecting results of async operations would be useful... What do you think?

[tolbertam]

Thanks for getting a start on this @rafalsiwiec! I think I agree with your sentiment. CachedGauges are very useful and I have used them quite a bit with dropwizard metrics. I've used the other two rarely, they have their use but I don't think they are needed right away. I'd be happy with default and CachedGauges to get started and we can always add the other implementations later.

I'll take a look at your PR tonight, thanks!

[tolbertam]

Fixed by #59, thanks @rafalsiwiec!