Add prometheus aggregation gateway
In order to start collecting real user FE metrics, we will need a prometheus aggregation gateway that can be scraped by prometheus.
https://github.com/weaveworks/prom-aggregation-gateway
I started on the clientside here: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/10570
This will POST
metrics to some configured endpoint every 15s. My first thought is that this endpoint would be in the rails app that would then proxy through to our aggregation gateway. I'm not sure if this is needed or a good idea as it will then have an impact on our rails infra.
One thing to note is that we've highlighted that we're probably the only users of GitLab that can get any value from this, so this gives us some flexibility but also some complications.
For example, I think it might be more OK to request the gateway directly if it's just for our custom setup.
But, also, seeing as this depends on clientside and rails code, there will still need to be some level of configuration within gitlab because that code will have to be included in the packaged product, unless we want to start building custom webpack bundles only for us. This is possible but I don't know if we want to add another step to releasing GitLab that only applies to us?
Note: This is not scheduled at all, just something we've been talking about for a long time that I'm interested in.