Add context to 2.0 storage interfaces

[AlekSi]

Having context.Context in Storage, Querier, Appender and probably few other types would be helpful for remote storages. Even if Prometheus will use context.TODO() in the first 2.0 release, having at least somewhat stable interface is a good thing.

I can implement it if you agree.

[gouthamve]

@AlekSi Thanks for the interest. Yes, the plan is to add context.Context to those types. The bigger issue is how you will plumb into the storage and its presented here: prometheus/tsdb#84

I think it makes sense to tackle the issue in tsdb first before we implement it in Prometheus as the wrapper is pretty thin.

[AlekSi]

Yepp, I saw that tsdb issue. This issue is about adding context to generic storage interfaces which, eventually, will be used for cancellation signals. How they will be handled depends on specific implementations, including tsdb. In the simplest case, they can just ignore them.
I'm prototyping remote storage implementation now, that's why I'm interested in adding contexts now rather then when/if tsdb support them.

[fabxc]

Yes, as you said it makes sense to add them to the shim layer now. We can than use it in tsdb later after figuring out our desired semantics. If you want to file a PR adding those, that would be great.

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On Thu, Jun 8, 2017 at 5:31 PM Alexey Palazhchenko ***@***.***> wrote: Yepp, I saw that tsdb issue. This issue is about adding context to generic storage interfaces which, eventually, will be used for cancellation signals. How they will be handled depends on specific implementations, including tsdb. In the simplest case, they can just ignore them. I'm prototyping remote storage implementation now, that's why I'm interested in adding contexts now rather then when/if tsdb support them. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#2823 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AEuA8iRZedMpzLaQyfFvC3I3OnNxxz8Mks5sCBPdgaJpZM4N0Lm8> .

[tomwilkie]

+1 I just came across the need for this working on the remote APIs for 2.0.

[AlekSi]

I can implement it if you agree.

We postponed that work. Feel free to work on it if you need it right now. I expect to return to it later.

[AlekSi]

Actively working on it again.
Update: Sorry, have to postpone it again.

[krasi-georgiev]

@AlekSi can we close this one since there is an open issue for the same in the tsdb repo
prometheus/tsdb#84

[AlekSi]

Please see discussion above why those are separate issues.

[krasi-georgiev]

yep , sorry. I missed some important bits on the first read.