fix: revoke partitions if lost (#20030)

Author: grobinson-grafana

pkg/limits/partition_lifecycler.go

@@ -74,30 +74,29 @@ func (l *partitionLifecycler) Assign(ctx context.Context, _ *kgo.Client, topics
 }
 
 // Revoke implements kgo.OnPartitionsRevoked.
-func (l *partitionLifecycler) Revoke(_ context.Context, _ *kgo.Client, topics map[string][]int32) {
+func (l *partitionLifecycler) Revoke(ctx context.Context, client *kgo.Client, topics map[string][]int32) {
+	l.revoke(ctx, client, topics)
+}
+
+// Lost implements kgo.OnPartitionsLost.
+func (l *partitionLifecycler) Lost(ctx context.Context, client *kgo.Client, topics map[string][]int32) {
+	l.revoke(ctx, client, topics)
+}
+
+// Revokes all partitions in topics. It expects just one topic and panics if
+// topics contains more than one topic.
+func (l *partitionLifecycler) revoke(_ context.Context, _ *kgo.Client, topics map[string][]int32) {
 	if len(topics) > 1 {
 		panic(fmt.Sprintf("expected one topic, received %d topics", len(topics)))
 	}
-	// We expect just one topic, and panic if topics contains more than one
-	// topic. The range over topics just makes it easier to access the first
-	// value in a map containing a single key.
+	// The range over topics just makes it easier to access the first value
+	// in a map containing a single key.
 	for _, partitions := range topics {
 		l.partitionManager.Revoke(partitions)
 		l.usage.EvictPartitions(partitions)
 	}
 }
 
-// Lost implements kgo.OnPartitionsLost.
-func (l *partitionLifecycler) Lost(_ context.Context, _ *kgo.Client, topics map[string][]int32) {
-	for _, partitions := range topics {
-		for _, partition := range partitions {
-			// TODO(grobinson): Implement logic to handle partition loss.
-			// For now, we just log the event to measure if it happens at all.
-			level.Warn(l.logger).Log("msg", "partition lost", "partition", partition)
-		}
-	}
-}
-
 func (l *partitionLifecycler) determineStateFromOffsets(ctx context.Context, partition int32) error {
 	logger := log.With(l.logger, "partition", partition)
 	// Get the start offset for the partition. This can be greater than zero