Idea: Add HTTP endpoint to show overrides.

[tomwilkie]

Like /ring, /user_stats etc.

[bboreham]

Should be quite similar to the /config endpoint.

[ethervoid]

Hi! First contributor attempt here!

Do you mind if I take this one as my first issue?

Thank you

[pstibrany]

Hi! First contributor attempt here!
Do you mind if I take this one as my first issue?

Not at all, please go ahead, and thank you!

[ethervoid]

Hi again!

I have some questions about this task to understand it better.

My first question is what is the expected output for the endpoint. My idea is to show a table with the different overrides for the different tenants but I want to confirm that.

Another question is about passing or gathering the overrides.

I've been taking a look at the code, first time using/viewing cortex, and I've seen there is no "quick" way to gather the overrides per user unless I know the user.

My first option was to include a new endpoint in the RegisterAPI and use the t.Overrides struct but that's not possible because:

• The initialization of overrides is after the API
• The overrides struct doesn't allow to get the raw limits information to show it.

I don't know if it's possible to get that information from the Config object but my idea is to register a new overrides endpoint here where I can get the map[string]*validation.Limits from the t.RuntimeConfig and iterate through that object to display the values but I'm not sure if that is the best approach or even if that is what is asked for, to be honest.

Thank you!

[bboreham]

I think it would be fine as a first step to show overrides for a single user.

I didn't follow what you meant about endpoints - could you take a look at how user_stats is implemented?
Main code is here: https://github.com/cortexproject/cortex/blob/8460a8871c7387f5bffc04f878f0815487465eca/pkg/distributor/http_admin.go
and http handler is added here:

cortex/pkg/api/api.go

Line 307 in 8460a88

a.RegisterRoute("/api/v1/user_stats", http.HandlerFunc(distributor.UserStatsHandler), true, "GET")

There is an all_user_stats path which might show an interesting contrast.

(BTW hit t in GitHub to get a URL against a specific commit, so it will still point to a valid place after the code has evolved)

[pracucci]

A previous comment states:

Should be quite similar to the /config endpoint.

I was expecting the overrides endpoint to just marshal (in YAML) the overrides and return it, like we do in /config. Ideally, the overrides endpoint should provide an easy way to get back the YAML overrides. Am I missing anything?

[bboreham]

That's probably a better idea.

@ethervoid let us know if you need pointers to how /config is implemented.

[ethervoid]

@pracucci @bboreham Thank you very much for your help!

I'll try to return the YAML of the overrides as suggested :)