Add Grafana image

[torkelo]

Checklist for Review

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• associated with or contacted upstream?
• does it fit into one of the common categories? ("service", "language stack", "base distribution")
• is it reasonably popular, or does it solve a particular use case well? Top 90 most popular project on GitHub
• does a documentation PR exist? (should be reviewed and merged at roughly the same time so that we don't have an empty image page on the Hub for very long)
• official-images maintainer dockerization review for best practices and cache gotchas/improvements (ala the official review guidelines)?
• 2+ official-images maintainer dockerization review?
• existing official images have been considered as a base? (ie, if foobar needs Node.js, has FROM node:... instead of grabbing node via other means been considered?)
• if FROM scratch, tarballs only exist in a single commit within the associated history?
• passes current tests? any simple new tests that might be appropriate to add? (https://github.com/docker-library/official-images/tree/master/test)

This image is similar to how elasticsearch/kibana is configured in that it's basing the image on our upstream image. This is preferable as the image publish step is after a long build & integration test process that validates the image & build, so would be good to just re-use the same image. https://github.com/grafana/grafana-docker-official

The upstream Dockerfile is at: https://github.com/grafana/grafana/blob/main/packaging/docker/Dockerfile

[tianon]

This image is similar to how elasticsearch/kibana is configured in that it's basing the image on our upstream image.

Unfortunately, the way the ELK images are currently structured was a one-time special case (and was only approved after a lot of back and forth and adjustments on both sides), and frankly it has gone very poorly. We do not plan to approve such a special case again.

[torkelo]

@tianon so if the Dockerfile instead downloads and installs a built tar.gz package is that ok?

So it would be basically this Dockerfile: https://github.com/grafana/grafana/blob/main/packaging/docker/Dockerfile

It currently relies on the build providing the built package in a prior step, if we replace that with a download & verification instead is that ok?

[tianon]

Yes, that approach is generally OK (you'll want to note #10794 and https://github.com/docker-library/faq#multi-stage-builds). 👍

I don't necessarily expect you to use any of it, but you might also find some parts of https://github.com/tianon/dockerfiles/blob/8356f896bbda16bf9e401dbaf2634c5880c6f88d/grafana/Dockerfile useful or interesting. 😇

(It's not super well-maintained/untouched since 2018 because I don't actually use that image anymore, but it's an OK example of the expected approach with a bit of software that's likely familiar. 😄)