delete stale correlations when datasources are deleted

pkg/services/correlations/correlations.go

@@ -4,12 +4,14 @@ import (
 	"context"
 
 	"github.com/grafana/grafana/pkg/api/routing"
+	"github.com/grafana/grafana/pkg/bus"
+	"github.com/grafana/grafana/pkg/events"
 	"github.com/grafana/grafana/pkg/infra/log"
 	"github.com/grafana/grafana/pkg/services/datasources"
 	"github.com/grafana/grafana/pkg/services/sqlstore"
 )
 
-func ProvideService(sqlStore *sqlstore.SQLStore, routeRegister routing.RouteRegister, datasourceService datasources.DataSourceService) *CorrelationsService {
+func ProvideService(sqlStore *sqlstore.SQLStore, routeRegister routing.RouteRegister, datasourceService datasources.DataSourceService, bus bus.Bus) *CorrelationsService {
 	s := &CorrelationsService{
 		SQLStore:          sqlStore,
 		RouteRegister:     routeRegister,
@@ -19,6 +21,8 @@ func ProvideService(sqlStore *sqlstore.SQLStore, routeRegister routing.RouteRegi
 
 	s.registerAPIEndpoints()
 
+	bus.AddEventListener(s.handleDatasourceDeletion)
+
 	return s
 }
 
@@ -41,3 +45,15 @@ func (s CorrelationsService) CreateCorrelation(ctx context.Context, cmd CreateCo
 func (s CorrelationsService) DeleteCorrelationsBySourceUID(ctx context.Context, cmd DeleteCorrelationsBySourceUIDCommand) error {
 	return s.deleteCorrelationsBySourceUID(ctx, cmd)
 }
+
+func (s CorrelationsService) handleDatasourceDeletion(ctx context.Context, event *events.DataSourceDeleted) error {
+	s.deleteCorrelationsBySourceUID(ctx, DeleteCorrelationsBySourceUIDCommand{
+		SourceUID: event.UID,
+	})
+
+	s.deleteCorrelationsByTargetUID(ctx, DeleteCorrelationsByTargetUIDCommand{
+		TargetUID: event.UID,
+	})
+
+	return nil
+}

pkg/services/correlations/database.go

@@ -70,5 +70,13 @@ func (s CorrelationsService) deleteCorrelationsBySourceUID(ctx context.Context,
 			return err
 		})
 	})
-
+}
+
+func (s CorrelationsService) deleteCorrelationsByTargetUID(ctx context.Context, cmd DeleteCorrelationsByTargetUIDCommand) error {
+	return s.SQLStore.WithDbSession(ctx, func(session *sqlstore.DBSession) error {
+		return s.SQLStore.InTransaction(ctx, func(ctx context.Context) error {
+			_, err := session.Delete(&Correlation{TargetUID: cmd.TargetUID})
+			return err
+		})
+	})
 }

pkg/services/correlations/models.go

@@ -51,3 +51,7 @@ type CreateCorrelationCommand struct {
 type DeleteCorrelationsBySourceUIDCommand struct {
 	SourceUID string
 }
+
+type DeleteCorrelationsByTargetUIDCommand struct {
+	TargetUID string
+}

pkg/services/sqlstore/datasource.go

@@ -123,8 +123,6 @@ func (ss *SQLStore) DeleteDataSource(ctx context.Context, cmd *datasources.Delet
 			}
 		}
 
-		// TODO: delete correlations having sourceUID or targetUID = cmd.UID
-
 		// Publish data source deletion event
 		sess.publishAfterCommit(&events.DataSourceDeleted{
 			Timestamp: time.Now(),