queryrange: retry: do not retry if context is canceled (#4562)

* query-frontend: do not log error if context is canceled

Example whenever the user cancels a query that is being executed:

```
{"caller":"retry.go:73","err":"context canceled","level":"error","msg":"error processing request","org_id":"anonymous","try":0,"ts":"2021-11-23T13:35:09.275914072Z"}
```

It doesn't mean anything bad so let's stop the spam. 

Signed-off-by: Giedrius Statkevičius <[email protected]>

Author: GiedriusS

CHANGELOG.md

@@ -5,6 +5,7 @@
 * [CHANGE] Changed default for `-ingester.min-ready-duration` from 1 minute to 15 seconds. #4539
 * [ENHANCEMENT] Query federation: improve performance in MergeQueryable by memoizing labels. #4502
 * [ENHANCEMENT] Added new ring related config `-ingester.readiness-check-ring-health` when enabled the readiness probe will succeed only after all instances are ACTIVE and healthy in the ring, this is enabled by default. #4539
+* [CHANGE] query-frontend: Do not print anything in the logs of `query-frontend` if a in-progress query has been canceled (context canceled). #4562
 * [ENHANCEMENT] Added new ring related config `-distributor.excluded-zones` when set this will exclude the comma-separated zones from the ring, default is "". #4539
 * [ENHANCEMENT] Upgraded Docker base images to `alpine:3.14`. #4514
 * [ENHANCEMENT] Updated Prometheus to latest. Includes changes from prometheus#9239, adding 15 new functions. Multiple TSDB bugfixes prometheus#9438 & prometheus#9381. #4524

pkg/querier/queryrange/retry.go

@@ -2,6 +2,7 @@ package queryrange
 
 import (
 	"context"
+	"errors"
 
 	"github.com/go-kit/log"
 	"github.com/go-kit/log/level"
@@ -66,6 +67,10 @@ func (r retry) Do(ctx context.Context, req Request) (Response, error) {
 			return resp, nil
 		}
 
+		if errors.Is(err, context.Canceled) {
+			return nil, err
+		}
+
 		// Retry if we get a HTTP 500 or a non-HTTP error.
 		httpResp, ok := httpgrpc.HTTPResponseFromError(err)
 		if !ok || httpResp.Code/100 == 5 {