Add SeriesIDSet() to Index interface

tsdb/engine/tsm1/engine_test.go

@@ -2404,9 +2404,7 @@ func (e *Engine) Reopen() error {
 // index. It will panic if the underlying index does not have a SeriesIDSet
 // method.
 func (e *Engine) SeriesIDSet() *tsdb.SeriesIDSet {
-	return e.index.(interface {
-		SeriesIDSet() *tsdb.SeriesIDSet
-	}).SeriesIDSet()
+	return e.index.SeriesIDSet()
 }
 
 // AddSeries adds the provided series data to the index and writes a point to

tsdb/index.go

@@ -37,6 +37,7 @@ type Index interface {
 	MeasurementsSketches() (estimator.Sketch, estimator.Sketch, error)
 	SeriesN() int64
 	SeriesSketches() (estimator.Sketch, estimator.Sketch, error)
+	SeriesIDSet() *SeriesIDSet
 
 	HasTagKey(name, key []byte) (bool, error)
 	HasTagValue(name, key, value []byte) (bool, error)

tsdb/store.go

@@ -655,12 +655,7 @@ func (s *Store) DeleteShard(shardID uint64) error {
 		return err
 	}
 
-	var ss *SeriesIDSet
-	if i, ok := index.(interface {
-		SeriesIDSet() *SeriesIDSet
-	}); ok {
-		ss = i.SeriesIDSet()
-	}
+	ss := index.SeriesIDSet()
 
 	db := sh.Database()
 	if err := sh.Close(); err != nil {
@@ -677,13 +672,7 @@ func (s *Store) DeleteShard(shardID uint64) error {
 			return err
 		}
 
-		if i, ok := index.(interface {
-			SeriesIDSet() *SeriesIDSet
-		}); ok {
-			ss.Diff(i.SeriesIDSet())
-		} else {
-			return fmt.Errorf("unable to get series id set for index in shard at %s", sh.Path())
-		}
+		ss.Diff(index.SeriesIDSet())
 		return nil
 	})
 
@@ -1015,16 +1004,11 @@ func (s *Store) SeriesCardinality(database string) (int64, error) {
 			return err
 		}
 
-		if i, ok := index.(interface {
-			SeriesIDSet() *SeriesIDSet
-		}); ok {
-			seriesIDs := i.SeriesIDSet()
-			setMu.Lock()
-			others = append(others, seriesIDs)
-			setMu.Unlock()
-		} else {
-			return fmt.Errorf("unable to get series id set for index in shard at %s", sh.Path())
-		}
+		seriesIDs := index.SeriesIDSet()
+		setMu.Lock()
+		others = append(others, seriesIDs)
+		setMu.Unlock()
+
 		return nil
 	})
 
@@ -1929,11 +1913,7 @@ func (s shardSet) ForEach(f func(ids *SeriesIDSet)) error {
 			return err
 		}
 
-		if t, ok := idx.(interface {
-			SeriesIDSet() *SeriesIDSet
-		}); ok {
-			f(t.SeriesIDSet())
-		}
+		f(idx.SeriesIDSet())
 	}
 	return nil
 }