Blocking certain queries in Thanos

[rkdutta]

Is your proposal related to a problem?

I want to block certain patterns of queries which are very expensive and lead to OOM errors.

Describe the solution you'd like

It would be great if we could provide a config containing a list of queries or patterns we would like to block. I see grafana mimir has support for this but so far I did not find any such option in Thanos.
https://grafana.com/docs/mimir/latest/configure/configure-blocked-queries/#configure-queries-to-block

Describe alternatives you've considered

(Write your answer here.)

Additional context

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[harry671003]

This feature was also implemented recently in Cortex. cortexproject/cortex#6005
It's just a matter of porting the changes to Thanos.

[rkdutta]

ok thanks for the quick response, I am not sure if there is a separate thread about porting the changes to Thanos.

[harry671003]

It's not being worked on currently. I was merely pointing out that we can copy most of the Cortex code as is into Thanos.

Thanks for submitting this feature request.

[rkdutta]

Thinking from user behavior..

If you go to explorer page in Grafana, select a thanos datasource and then you specify the labels before you set the metric, this creates a very open-ended query to the backend and leads to OOM. I have seen people doing this many times. I don't know yet how to block this behavioral pattern.

Maybe it's a good idea to have a solution that does not allow querying if the metric name is missing or if the minimum number of labels is less than an acceptable number. Just thought of sharing my 2 cents.