Alerting/Annotations: Return nothing from historian store if filtering by tags and matchAny is false (#85488)

* Return nothing from historian store if filtering by tag

pkg/services/annotations/annotationsimpl/loki/historian_store.go

@@ -78,6 +78,12 @@ func (r *LokiHistorianStore) Get(ctx context.Context, query *annotations.ItemQue
 		return make([]*annotations.ItemDTO, 0), nil
 	}
 
+	// if the query is filtering on tags, but not on a specific dashboard, we shouldn't query loki
+	// since state history won't have tags for annotations
+	if len(query.Tags) > 0 && query.DashboardID == 0 && query.DashboardUID == "" {
+		return make([]*annotations.ItemDTO, 0), nil
+	}
+
 	rule := &ngmodels.AlertRule{}
 	if query.AlertID != 0 {
 		var err error
@@ -173,7 +179,7 @@ func (r *LokiHistorianStore) annotationsFromStream(stream historian.Stream, ac a
 }
 
 func (r *LokiHistorianStore) GetTags(ctx context.Context, query *annotations.TagsQuery) (annotations.FindTagsResult, error) {
-	return annotations.FindTagsResult{}, nil
+	return annotations.FindTagsResult{Tags: []*annotations.TagsDTO{}}, nil
 }
 
 // util

pkg/services/annotations/annotationsimpl/loki/historian_store_test.go

@@ -254,6 +254,32 @@ func TestIntegrationAlertStateHistoryStore(t *testing.T) {
 				lastTime = item.Time
 			}
 		})
+
+		t.Run("should return nothing if query is for tags only", func(t *testing.T) {
+			fakeLokiClient.rangeQueryRes = []historian.Stream{
+				historian.StatesToStream(ruleMetaFromRule(t, dashboardRules[dashboard1.UID][0]), transitions, map[string]string{}, log.NewNopLogger()),
+				historian.StatesToStream(ruleMetaFromRule(t, dashboardRules[dashboard1.UID][1]), transitions, map[string]string{}, log.NewNopLogger()),
+			}
+
+			query := annotations.ItemQuery{
+				OrgID: 1,
+				From:  start.UnixMilli(),
+				To:    start.Add(time.Second * time.Duration(numTransitions+1)).UnixMilli(),
+				Tags:  []string{"tag1"},
+			}
+			res, err := store.Get(
+				context.Background(),
+				&query,
+				&annotation_ac.AccessResources{
+					Dashboards: map[string]int64{
+						dashboard1.UID: dashboard1.ID,
+					},
+					CanAccessDashAnnotations: true,
+				},
+			)
+			require.NoError(t, err)
+			require.Empty(t, res)
+		})
 	})
 
 	t.Run("Testing items from Loki stream", func(t *testing.T) {