Fetch label values from index

pkg/ingester/instance.go

@@ -589,9 +589,28 @@ type UniqueValues map[string]struct{}
 
 // LabelsWithValues returns the label names with all the unique values depending on the request
 func (i *instance) LabelsWithValues(ctx context.Context, startTime time.Time, matchers ...*labels.Matcher) (map[string]UniqueValues, error) {
-	// TODO (shantanu): Figure out how to get the label names from index directly when no matchers are given.
-
 	labelMap := make(map[string]UniqueValues)
+	if len(matchers) == 0 {
+		labelsFromIndex, err := i.index.LabelNames(startTime, nil)
+		if err != nil {
+			return nil, err
+		}
+
+		for _, label := range labelsFromIndex {
+			values, err := i.index.LabelValues(startTime, label, nil)
+			if err != nil {
+				return nil, err
+			}
+			existingValues, exists := labelMap[label]
+			if !exists {
+				existingValues = make(map[string]struct{})
+			}
+			for _, v := range values {
+				existingValues[v] = struct{}{}
+			}
+		}
+	}
+
 	err := i.forMatchingStreams(ctx, startTime, matchers, nil, func(s *stream) error {
 		for _, label := range s.labels {
 			v, exists := labelMap[label.Name]

pkg/querier/queryrange/codec.go

@@ -268,18 +268,6 @@ type DetectedLabelsRequest struct {
 	logproto.DetectedLabelsRequest
 }
 
-// NewDetectedLabelsRequest creates a new request for detected labels
-func NewDetectedLabelsRequest(start, end time.Time, query, path string) *DetectedLabelsRequest {
-	return &DetectedLabelsRequest{
-		DetectedLabelsRequest: logproto.DetectedLabelsRequest{
-			Start: &start,
-			End:   &end,
-			Query: query,
-		},
-		path: path,
-	}
-}
-
 func (r *DetectedLabelsRequest) AsProto() *logproto.DetectedLabelsRequest {
 	return &r.DetectedLabelsRequest
 }