fix: draining strategy fetch

pkg/file/redundancy/getter/getter.go

@@ -19,6 +19,7 @@ import (
 var (
 	errStrategyNotAllowed = errors.New("strategy not allowed")
 	errStrategyFailed     = errors.New("strategy failed")
+	errShouldNeverHappen  = errors.New("should never happen")
 )
 
 // decoder is a private implementation of storage.Getter
@@ -240,15 +241,24 @@ func (g *decoder) runStrategy(s Strategy) error {
 	c := make(chan error, len(m))
 
 	ctx, cancel := context.WithCancel(context.Background())
-	defer cancel()
+	completed := 0
+	defer func() {
+		cancel()
+		remaining := len(m) - completed
+		for i := 0; i < remaining; i++ {
+			<-c
+		}
+	}()
 
 	for _, i := range m {
 		go func(i int) {
 			c <- g.fetch(ctx, i, false)
 		}(i)
 	}
 
-	for range c {
+	for completed < len(m) {
+		<-c
+		completed++
 		if g.fetchedCnt.Load() >= int32(g.shardCnt) {
 			return nil
 		}
@@ -257,7 +267,7 @@ func (g *decoder) runStrategy(s Strategy) error {
 		}
 	}
 
-	return nil
+	return errShouldNeverHappen
 }
 
 // recover wraps the stages of data shard recovery: