Add version string to metrics

[steled]

Feature Description

Hi,

I'm monitoring my Gitea instance via Prometheus and Grafana.
It would be great to have a string for the current Gitea version and the new one in the metrics to set an Grafana alert for possible new version on it.

Screenshots

No response

[Flygrounder]

Sounds like a useful feature. But Prometheus does not support string metrics and adding version string as a label does not sound like a good idea.

Maybe we should convert semver to an integer e.g. 1.15.9 = 1 * 100^2 + 15 * 100 + 9 = 11509

[techknowlogick]

@Flygrounder that's a good suggestion, although I'm not sure it'd work in all cases, as there are occasions when the version wouldn't always be in a format that could be converted so cleanly, ex v1.16.0-dev-796-gd228d346c

[Flygrounder]

But this is only the case with dev versions, for which you probably do not want to get alerts because they are constantly updated. Perhaps in that case reporting 11600 would be fine.

[wxiaoguang]

I think we had better keep the original version format, and just use a new field like updateAvailable to indicate that there is a new update. Converting a version string to an (big) integer may introduce new problems.

[Flygrounder]

To be clear, I was talking only about converting semver to an integer in Prometheus metrics, not for the entire project.

Additional benefit of having version metric in contrast to updateAvailable is that you can correlate other metrics to the specific Gitea version and see how well each version performs.

[6543]

#18454 (review)

[mwasilew2]

I think that what you use for "semi-automated" upgrades or upgrade notifications varies from environment to environment and it would be hard to provide a unified approach. This is not to say that Gitea shouldn't include an approach for that (e.g. a notification in the admin panel or an email sent to the Gitea admins saying that a new version is available).

I'm not sure what would be the best approach to populating a Prometheus metric with the latest available version of Gitea.

Some ideas for how to approach the problem of picking up new versions automatically:

• https://github.com/containrrr/watchtower
• https://github.com/renovatebot/renovate

Regardless of the mechanism used for updating, I think it's still useful to expose build info, so I opened: #22819

[delvh]

This is not to say that Gitea shouldn't include an approach for that (e.g. a notification in the admin panel or an email sent to the Gitea admins saying that a new version is available).

FYI: That exists already. https://docs.gitea.io/en-us/config-cheat-sheet/#cron----check-for-new-gitea-versions-cronupdate_checker

[lunny]

resolved by #22819