loki: backend mode: support all query types (#45619)

* loki: backend mode: support all query types * loki: backend: adjust vector-parsing field-names * loki: backend: no interval for streams-dataframes * loki: backend: enable more query types * better variable name * removed unnecessary code * improve frame-processing * more unit tests * improved code Co-authored-by: Ivana Huckova <30407135+ivanahuckova@users.noreply.github.com> * remove unused code Co-authored-by: Ivana Huckova <30407135+ivanahuckova@users.noreply.github.com> * simplify code Co-authored-by: Ivana Huckova <30407135+ivanahuckova@users.noreply.github.com> * lint fix Co-authored-by: Ivana Huckova <30407135+ivanahuckova@users.noreply.github.com>
2022-02-25 09:14:17 +01:00
parent a578cf0f7c
commit 1cad35ea67
19 changed files with 966 additions and 131 deletions
@@ -0,0 +1,108 @@
+package loki
+
+import (
+	"testing"
+	"time"
+
+	"github.com/google/go-cmp/cmp"
+	"github.com/grafana/grafana-plugin-sdk-go/data"
+	"github.com/grafana/loki/pkg/loghttp"
+	p "github.com/prometheus/common/model"
+	"github.com/stretchr/testify/require"
+)
+
+func TestParseResponse(t *testing.T) {
+	t.Run("value is not of supported type", func(t *testing.T) {
+		value := loghttp.QueryResponse{
+			Data: loghttp.QueryResponseData{
+				Result: loghttp.Scalar{},
+			},
+		}
+		res, err := parseResponse(&value, nil)
+		require.Equal(t, len(res), 0)
+		require.Error(t, err)
+	})
+
+	t.Run("response should be parsed normally", func(t *testing.T) {
+		values := []p.SamplePair{
+			{Value: 1, Timestamp: 1000},
+			{Value: 2, Timestamp: 2000},
+			{Value: 3, Timestamp: 3000},
+			{Value: 4, Timestamp: 4000},
+			{Value: 5, Timestamp: 5000},
+		}
+		value := loghttp.QueryResponse{
+			Data: loghttp.QueryResponseData{
+				Result: loghttp.Matrix{
+					p.SampleStream{
+						Metric: p.Metric{"app": "Application", "tag2": "tag2"},
+						Values: values,
+					},
+				},
+			},
+		}
+
+		query := &lokiQuery{
+			Expr:         "up(ALERTS)",
+			QueryType:    QueryTypeRange,
+			LegendFormat: "legend {{app}}",
+			Step:         time.Second * 42,
+		}
+		frame, err := parseResponse(&value, query)
+		require.NoError(t, err)
+
+		labels, err := data.LabelsFromString("app=Application, tag2=tag2")
+		require.NoError(t, err)
+		field1 := data.NewField("time", nil, []time.Time{
+			time.Date(1970, 1, 1, 0, 0, 1, 0, time.UTC),
+			time.Date(1970, 1, 1, 0, 0, 2, 0, time.UTC),
+			time.Date(1970, 1, 1, 0, 0, 3, 0, time.UTC),
+			time.Date(1970, 1, 1, 0, 0, 4, 0, time.UTC),
+			time.Date(1970, 1, 1, 0, 0, 5, 0, time.UTC),
+		})
+		field1.Config = &data.FieldConfig{Interval: float64(42000)}
+		field2 := data.NewField("value", labels, []float64{1, 2, 3, 4, 5})
+		field2.SetConfig(&data.FieldConfig{DisplayNameFromDS: "legend Application"})
+		testFrame := data.NewFrame("legend Application", field1, field2)
+		testFrame.SetMeta(&data.FrameMeta{
+			ExecutedQueryString: "Expr: up(ALERTS)\nStep: 42s",
+		})
+
+		if diff := cmp.Diff(testFrame, frame[0], data.FrameTestCompareOptions()...); diff != "" {
+			t.Errorf("Result mismatch (-want +got):\n%s", diff)
+		}
+	})
+
+	t.Run("should set interval-attribute in response", func(t *testing.T) {
+		values := []p.SamplePair{
+			{Value: 1, Timestamp: 1000},
+		}
+		value := loghttp.QueryResponse{
+			Data: loghttp.QueryResponseData{
+				Result: loghttp.Matrix{
+					p.SampleStream{
+						Values: values,
+					},
+				},
+			},
+		}
+
+		query := &lokiQuery{
+			Step:      time.Second * 42,
+			QueryType: QueryTypeRange,
+		}
+
+		frames, err := parseResponse(&value, query)
+		require.NoError(t, err)
+
+		// to keep the test simple, we assume the
+		// first field is the time-field
+		timeField := frames[0].Fields[0]
+		require.NotNil(t, timeField)
+		require.Equal(t, data.FieldTypeTime, timeField.Type())
+
+		timeFieldConfig := timeField.Config
+		require.NotNil(t, timeFieldConfig)
+		require.Equal(t, float64(42000), timeFieldConfig.Interval)
+	})
+}