Truncate labels for error messages (#71)

Author: hczhu-db

pkg/receive/multitsdb.go

@@ -141,7 +141,7 @@ func (l *localClient) String() string {
 	mint, maxt := l.store.TimeRange()
 	return fmt.Sprintf(
 		"LabelSets: %v MinTime: %d MaxTime: %d",
-		labelpb.PromLabelSetsToStringN(l.LabelSets(), 10), mint, maxt,
+		labelpb.PromLabelSetsToStringN(l.LabelSets(), 500), mint, maxt,
 	)
 }
 

pkg/store/labelpb/label.go

@@ -303,15 +303,18 @@ func ExtendSortedLabels(lset, extend labels.Labels) labels.Labels {
 }
 
 func PromLabelSetsToString(lsets []labels.Labels) string {
-	return PromLabelSetsToStringN(lsets, 1000000)
+	return PromLabelSetsToStringN(lsets, 500)
 }
 
-func PromLabelSetsToStringN(lsets []labels.Labels, maxNumLabels int) string {
+func PromLabelSetsToStringN(lsets []labels.Labels, maxLength int) string {
+	if len(lsets) == 0 {
+		return ""
+	}
 	s := []string{}
 	for _, ls := range lsets {
 		s = append(s, ls.String())
-		maxNumLabels--
-		if maxNumLabels <= 0 {
+		maxLength -= len(ls.String())
+		if maxLength <= 0 {
 			break
 		}
 	}

pkg/store/proxy.go

@@ -464,14 +464,16 @@ func (s *ProxyStore) Series(originalRequest *storepb.SeriesRequest, srv storepb.
 
 		if resp.GetWarning() != "" {
 			totalFailedStores++
-			level.Error(s.logger).Log("msg", "Series: warning from store", "warning", resp.GetWarning())
+			maxWarningBytes := 2000
+			warning := resp.GetWarning()[:min(maxWarningBytes, len(resp.GetWarning()))]
+			level.Error(s.logger).Log("msg", "Series: warning from store", "warning", warning)
 			if r.PartialResponseStrategy == storepb.PartialResponseStrategy_GROUP_REPLICA {
 				// TODO: attribute the warning to the store(group key and replica key) that produced it.
 				// Each client streams a sequence of time series, so it's not trivial to attribute the warning to a specific client.
 				if totalFailedStores > 1 {
 					level.Error(reqLogger).Log("msg", "more than one stores have failed")
 					// If we don't know which store has failed, we can tolerate at most one failed store.
-					return status.Error(codes.Aborted, resp.GetWarning())
+					return status.Error(codes.Aborted, warning)
 				}
 			} else if r.PartialResponseDisabled || r.PartialResponseStrategy == storepb.PartialResponseStrategy_ABORT {
 				return status.Error(codes.Aborted, resp.GetWarning())