Testdata: add random labeled stream (#41932)

pkg/tsdb/testdatasource/stream_handler.go

@@ -27,6 +27,13 @@ func (s *Service) SubscribeStream(_ context.Context, req *backend.SubscribeStrea
 		}
 	}
 
+	if strings.Contains(req.Path, "-labeled") {
+		initialData, err = backend.NewInitialFrame(s.labelFrame, data.IncludeSchemaOnly)
+		if err != nil {
+			return nil, err
+		}
+	}
+
 	if s.cfg.FeatureToggles["live-pipeline"] {
 		// While developing Live pipeline avoid sending initial data.
 		initialData = nil
@@ -58,6 +65,12 @@ func (s *Service) RunStream(ctx context.Context, request *backend.RunStreamReque
 			Interval: 100 * time.Millisecond,
 			Drop:     0.75, // keep 25%
 		}
+	case "random-labeled-stream":
+		conf = testStreamConfig{
+			Interval: 200 * time.Millisecond,
+			Drop:     0.2, // keep 80%
+			Labeled:  true,
+		}
 	case "random-20Hz-stream":
 		conf = testStreamConfig{
 			Interval: 50 * time.Millisecond,
@@ -77,6 +90,7 @@ type testStreamConfig struct {
 	Interval time.Duration
 	Drop     float64
 	Flight   *flightConfig
+	Labeled  bool
 }
 
 func (s *Service) runTestStream(ctx context.Context, path string, conf testStreamConfig, sender *backend.StreamSender) error {
@@ -92,6 +106,12 @@ func (s *Service) runTestStream(ctx context.Context, path string, conf testStrea
 		flight.append(conf.Flight.getNextPoint(time.Now()))
 	}
 
+	labelFrame := data.NewFrame("labeled",
+		data.NewField("labels", nil, make([]string, 2)),
+		data.NewField("Time", nil, make([]time.Time, 2)),
+		data.NewField("Value", nil, make([]float64, 2)),
+	)
+
 	for {
 		select {
 		case <-ctx.Done():
@@ -116,12 +136,28 @@ func (s *Service) runTestStream(ctx context.Context, path string, conf testStrea
 				delta := rand.Float64() - 0.5
 				walker += delta
 
-				s.frame.Fields[0].Set(0, t)
-				s.frame.Fields[1].Set(0, walker)                                // Value
-				s.frame.Fields[2].Set(0, walker-((rand.Float64()*spread)+0.01)) // Min
-				s.frame.Fields[3].Set(0, walker+((rand.Float64()*spread)+0.01)) // Max
-				if err := sender.SendFrame(s.frame, mode); err != nil {
-					return err
+				if conf.Labeled {
+					secA := t.Second() / 3
+					secB := t.Second() / 7
+
+					labelFrame.Fields[0].Set(0, fmt.Sprintf("s=A,s=p%d,x=X", secA))
+					labelFrame.Fields[1].Set(0, t)
+					labelFrame.Fields[2].Set(0, walker)
+
+					labelFrame.Fields[0].Set(1, fmt.Sprintf("s=B,s=p%d,x=X", secB))
+					labelFrame.Fields[1].Set(1, t)
+					labelFrame.Fields[2].Set(1, walker+10)
+					if err := sender.SendFrame(labelFrame, mode); err != nil {
+						return err
+					}
+				} else {
+					s.frame.Fields[0].Set(0, t)
+					s.frame.Fields[1].Set(0, walker)                                // Value
+					s.frame.Fields[2].Set(0, walker-((rand.Float64()*spread)+0.01)) // Min
+					s.frame.Fields[3].Set(0, walker+((rand.Float64()*spread)+0.01)) // Max
+					if err := sender.SendFrame(s.frame, mode); err != nil {
+						return err
+					}
 				}
 			}
 		}