[v9.4.x] Alerting: Fix Classic Conditions $values variable (#64249)

Alerting: Fix Classic Conditions $values variable (#64243)

This commit fixes a bug in the $values variable in notification
templates when using Classic Conditions. Since Classic Conditions
are not multi-dimensional, the values of each series that exceeded
the condition should be available as a RefID and offset. For example,
B0, B1, etc. However, this bug meant that instead just a single
condition would be printed as B, not B0.

(cherry picked from commit ed71012ced)

Co-authored-by: George Robinson <george.robinson@grafana.com>

pkg/services/ngalert/state/cache.go

@@ -52,11 +52,11 @@ func (rs *ruleStates) getOrCreate(ctx context.Context, log log.Logger, alertRule
 	ruleLabels, annotations := rs.expandRuleLabelsAndAnnotations(ctx, log, alertRule, result, extraLabels, externalURL)
 
 	values := make(map[string]float64)
-	for _, v := range result.Values {
+	for refID, v := range result.Values {
 		if v.Value != nil {
-			values[v.Var] = *v.Value
+			values[refID] = *v.Value
 		} else {
-			values[v.Var] = math.NaN()
+			values[refID] = math.NaN()
 		}
 	}
 

pkg/services/ngalert/state/cache_test.go

@@ -9,6 +9,7 @@ import (
 	"github.com/grafana/grafana-plugin-sdk-go/data"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
+	"github.com/xorcare/pointer"
 
 	"github.com/grafana/grafana/pkg/infra/log"
 	"github.com/grafana/grafana/pkg/services/ngalert/eval"
@@ -108,6 +109,7 @@ func Test_getOrCreate(t *testing.T) {
 			assert.Equal(t, expected, state.Labels["rule-"+key])
 		}
 	})
+
 	t.Run("rule annotations should be able to be expanded with result and extra labels", func(t *testing.T) {
 		result := eval.Result{
 			Instance: models.GenerateAlertLabels(5, "result-"),
@@ -134,6 +136,34 @@ func Test_getOrCreate(t *testing.T) {
 			assert.Equal(t, expected, state.Annotations["rule-"+key])
 		}
 	})
+
+	t.Run("expected Reduce and Math expression values", func(t *testing.T) {
+		result := eval.Result{
+			Instance: models.GenerateAlertLabels(5, "result-"),
+			Values: map[string]eval.NumberValueCapture{
+				"A": eval.NumberValueCapture{Var: "A", Value: pointer.Float64(1.0)},
+				"B": eval.NumberValueCapture{Var: "B", Value: pointer.Float64(2.0)},
+			},
+		}
+		rule := generateRule()
+
+		state := c.getOrCreate(context.Background(), l, rule, result, nil, url)
+		assert.Equal(t, map[string]float64{"A": 1, "B": 2}, state.Values)
+	})
+
+	t.Run("expected Classic Condition values", func(t *testing.T) {
+		result := eval.Result{
+			Instance: models.GenerateAlertLabels(5, "result-"),
+			Values: map[string]eval.NumberValueCapture{
+				"B0": eval.NumberValueCapture{Var: "B", Value: pointer.Float64(1.0)},
+				"B1": eval.NumberValueCapture{Var: "B", Value: pointer.Float64(2.0)},
+			},
+		}
+		rule := generateRule()
+
+		state := c.getOrCreate(context.Background(), l, rule, result, nil, url)
+		assert.Equal(t, map[string]float64{"B0": 1, "B1": 2}, state.Values)
+	})
 }
 
 func Test_mergeLabels(t *testing.T) {