TestData: add simple scenario with GPS and altitude coordinates (#36011)

2021-06-22 14:19:29 -07:00
parent f0cac149da
commit 8ad9834019
5 changed files with 258 additions and 8 deletions
@@ -0,0 +1,135 @@
+package testdatasource
+
+import (
+	"context"
+	"fmt"
+	"math"
+	"time"
+
+	"github.com/grafana/grafana-plugin-sdk-go/backend"
+	"github.com/grafana/grafana-plugin-sdk-go/data"
+	"github.com/grafana/grafana/pkg/components/simplejson"
+)
+
+func (p *testDataPlugin) handleFlightPathScenario(ctx context.Context, req *backend.QueryDataRequest) (*backend.QueryDataResponse, error) {
+	resp := backend.NewQueryDataResponse()
+
+	for _, q := range req.Queries {
+		_, err := simplejson.NewJson(q.JSON)
+		if err != nil {
+			return nil, fmt.Errorf("failed to parse query json: %v", err)
+		}
+
+		timeWalkerMs := q.TimeRange.From.UnixNano() / int64(time.Millisecond)
+		to := q.TimeRange.To.UnixNano() / int64(time.Millisecond)
+		stepMillis := q.Interval.Milliseconds()
+
+		cfg := newFlightConfig()
+
+		maxPoints := q.MaxDataPoints * 2
+		f := cfg.initFields()
+		for i := int64(0); i < maxPoints && timeWalkerMs < to; i++ {
+			t := time.Unix(timeWalkerMs/int64(1e+3), (timeWalkerMs%int64(1e+3))*int64(1e+6))
+			f.append(cfg.getNextPoint(t))
+
+			timeWalkerMs += stepMillis
+		}
+
+		// When close to now, link to the live streaming channel
+		if q.TimeRange.To.Add(time.Second * 2).After(time.Now()) {
+			f.frame.Meta = &data.FrameMeta{
+				Channel: "plugin/testdata/flight-5hz-stream",
+			}
+		}
+
+		respD := resp.Responses[q.RefID]
+		respD.Frames = append(respD.Frames, f.frame)
+		resp.Responses[q.RefID] = respD
+	}
+
+	return resp, nil
+}
+
+type flightDataPoint struct {
+	time     time.Time
+	lat      float64 // gps
+	lng      float64 // gps
+	heading  float64 // degree
+	altitude float64 // above ground
+}
+
+type flightConfig struct {
+	centerLat   float64
+	centerLng   float64
+	radius      float64
+	altitudeMin float64
+	altitudeMax float64
+	periodS     float64 // angular speed
+}
+
+func newFlightConfig() *flightConfig {
+	return &flightConfig{
+		centerLat:   37.773972, // San francisco
+		centerLng:   -122.431297,
+		radius:      0.1, // raw gps degrees
+		altitudeMin: 350,
+		altitudeMax: 400,
+		periodS:     10, //model.Get("period").MustFloat64(10),
+	}
+}
+
+type flightFields struct {
+	time     *data.Field
+	lat      *data.Field
+	lng      *data.Field
+	heading  *data.Field
+	altitude *data.Field
+
+	frame *data.Frame
+}
+
+func (f *flightConfig) initFields() *flightFields {
+	ff := &flightFields{
+		time:     data.NewFieldFromFieldType(data.FieldTypeTime, 0),
+		lat:      data.NewFieldFromFieldType(data.FieldTypeFloat64, 0),
+		lng:      data.NewFieldFromFieldType(data.FieldTypeFloat64, 0),
+		heading:  data.NewFieldFromFieldType(data.FieldTypeFloat64, 0),
+		altitude: data.NewFieldFromFieldType(data.FieldTypeFloat64, 0),
+	}
+	ff.time.Name = "time"
+	ff.lat.Name = "lat"
+	ff.lng.Name = "lng"
+	ff.heading.Name = "heading"
+	ff.altitude.Name = "altitude"
+
+	ff.frame = data.NewFrame("", ff.time, ff.lat, ff.lng, ff.heading, ff.altitude)
+	return ff
+}
+
+func (f *flightFields) append(v flightDataPoint) {
+	f.frame.AppendRow(v.time, v.lat, v.lng, v.heading, v.altitude)
+}
+
+func (f *flightFields) set(idx int, v flightDataPoint) {
+	f.time.Set(idx, v.time)
+	f.lat.Set(idx, v.lat)
+	f.lng.Set(idx, v.lng)
+	f.heading.Set(idx, v.heading)
+	f.altitude.Set(idx, v.altitude)
+}
+
+func (f *flightConfig) getNextPoint(t time.Time) flightDataPoint {
+	periodNS := int64(f.periodS * float64(time.Second))
+	ms := t.UnixNano() % periodNS
+	per := float64(ms) / float64(periodNS)
+	rad := per * 2.0 * math.Pi // 0 >> 2Pi
+	delta := f.altitudeMax - f.altitudeMin
+
+	return flightDataPoint{
+		time:     t,
+		lat:      f.centerLat + math.Sin(rad)*f.radius,
+		lng:      f.centerLng + math.Sin(rad+math.Pi)*f.radius,
+		heading:  (rad * 180) / math.Pi,         // (math.Atanh(rad) * 180.0) / math.Pi, // in degrees
+		altitude: f.altitudeMin + (delta * per), // clif
+	}
+}