Add LabelValues.Close method

Signed-off-by: Arve Knudsen <[email protected]>

storage/interface.go

@@ -466,4 +466,6 @@ type LabelValues interface {
 	// Warnings is a collection of warnings that have occurred during iteration.
 	// Warnings could be non-empty even if iteration has not failed with an error.
 	Warnings() annotations.Annotations
+	// Close the iterator.
+	Close() error
 }

storage/merge.go

@@ -310,6 +310,10 @@ func (m *mergedLabelValues) Warnings() annotations.Annotations {
 	return m.warnings
 }
 
+func (m *mergedLabelValues) Close() error {
+	return nil
+}
+
 // errLabelValues is an empty label values iterator with an error.
 type errLabelValues struct {
 	err      error
@@ -320,6 +324,7 @@ func (e errLabelValues) Next() bool                        { return false }
 func (e errLabelValues) At() string                        { return "" }
 func (e errLabelValues) Err() error                        { return e.err }
 func (e errLabelValues) Warnings() annotations.Annotations { return e.warnings }
+func (e errLabelValues) Close() error                      { return nil }
 
 // ErrLabelValues returns a LabelValues with err.
 func ErrLabelValues(err error) LabelValues {

storage/merge_test.go

@@ -1351,6 +1351,10 @@ func (l *labelValuesList) Warnings() annotations.Annotations {
 	return l.warnings
 }
 
+func (*labelValuesList) Close() error {
+	return nil
+}
+
 func (m *mockGenericQuerier) LabelNames(context.Context, ...*labels.Matcher) ([]string, annotations.Annotations, error) {
 	m.mtx.Lock()
 	m.labelNamesCalls++

storage/secondary.go

@@ -87,6 +87,10 @@ func (s *secondaryLabelValues) Warnings() annotations.Annotations {
 	return ws
 }
 
+func (s *secondaryLabelValues) Close() error {
+	return nil
+}
+
 func (s *secondaryQuerier) LabelNames(ctx context.Context, matchers ...*labels.Matcher) ([]string, annotations.Annotations, error) {
 	names, w, err := s.genericQuerier.LabelNames(ctx, matchers...)
 	if err != nil {

tsdb/index/labelvalues.go

@@ -106,6 +106,10 @@ func (l *labelValuesV2) Warnings() annotations.Annotations {
 	return nil
 }
 
+func (l *labelValuesV2) Close() error {
+	return nil
+}
+
 type labelValuesV1 struct {
 	it       *reflect.MapIter
 	matchers []*labels.Matcher
@@ -145,6 +149,10 @@ func (*labelValuesV1) Warnings() annotations.Annotations {
 	return nil
 }
 
+func (*labelValuesV1) Close() error {
+	return nil
+}
+
 func (r *Reader) LabelValuesIntersectingPostings(name string, postings Postings) storage.LabelValues {
 	if r.version == FormatV1 {
 		/* TODO
@@ -258,6 +266,10 @@ func (it *intersectLabelValues) Warnings() annotations.Annotations {
 	return nil
 }
 
+func (it *intersectLabelValues) Close() error {
+	return nil
+}
+
 // ListLabelValues is an iterator over a slice of label values.
 type ListLabelValues struct {
 	cur    string
@@ -292,6 +304,10 @@ func (*ListLabelValues) Warnings() annotations.Annotations {
 	return nil
 }
 
+func (*ListLabelValues) Close() error {
+	return nil
+}
+
 func (p *MemPostings) LabelValuesIntersectingPostings(name string, postings Postings) storage.LabelValues {
 	p.mtx.RLock()
 	defer p.mtx.RUnlock()