Passthrough controller now subscribes to next controller. #20

Embarcadero · Dec 7, 2024 · 3783251 · 3783251
1 parent 6eea3b6
commit 3783251
Showing 1 changed file with 29 additions and 2 deletions.
diff --git a/Source/BoldPersistenceControllerPassthrough.pas b/Source/BoldPersistenceControllerPassthrough.pas
@@ -22,10 +22,14 @@   TBoldPersistenceControllerPassthrough = class;
   { TBoldPersistenceControllerPassthrough }
   TBoldPersistenceControllerPassthrough = class(TBoldPersistenceController)
   private
+    fSubscriber: TBoldPassthroughSubscriber;
     fNextPersistenceController: TBoldPersistenceController;
     function GetNextPersistenceController: TBoldPersistenceController;
+    procedure SetNextPersistenceController(const Value: TBoldPersistenceController);
+    procedure Receive(Originator: TObject; OriginalEvent: TBoldEvent; RequestedEvent: TBoldRequestedEvent);
   public
     constructor Create;
+    destructor Destroy; override;
     procedure PMExactifyIds(ObjectIdList: TBoldObjectIdList; TranslationList: TBoldIdTranslationList; HandleNonExisting: Boolean); override;
     procedure PMFetch(ObjectIdList: TBoldObjectIdList; ValueSpace: IBoldValueSpace; MemberIdList: TBoldMemberIdList; FetchMode: Integer; BoldClientID: TBoldClientID); override;
     procedure PMFetchIDListWithCondition(ObjectIdList: TBoldObjectIdList; ValueSpace: IBoldValueSpace; FetchMode: Integer; Condition: TBoldCondition; BoldClientID: TBoldClientID); override;
@@ -43,8 +47,7 @@   TBoldPersistenceControllerPassthrough = class(TBoldPersistenceController)
     procedure CommitTransaction; override;
     procedure RollbackTransaction; override;
     function DatabaseInterface: IBoldDatabase; override;
-    property NextPersistenceController: TBoldPersistenceController read getNextPersistenceController
-              write fNextPersistenceController;
+    property NextPersistenceController: TBoldPersistenceController read GetNextPersistenceController write SetNextPersistenceController;
   end;
 
 implementation
@@ -63,6 +66,17 @@ function TBoldPersistenceControllerPassthrough.CanEvaluateInPS(sOCL: string;
   Result := NextPersistenceController.CanEvaluateInPS(sOCL, aSystem, aContext, aVariableList);
 end;
 
+procedure TBoldPersistenceControllerPassthrough.SetNextPersistenceController(const Value: TBoldPersistenceController);
+begin
+  if fNextPersistenceController <> value then
+  begin
+    fNextPersistenceController := Value;
+    FreeAndNil(fSubscriber);
+    fSubscriber := TBoldPassthroughSubscriber.Create(Receive);
+    fNextPersistenceController.AddSubscription(fSubscriber, beDestroying);
+  end;
+end;
+
 procedure TBoldPersistenceControllerPassthrough.StartTransaction;
 begin
   NextPersistenceController.StartTransaction;
@@ -91,6 +105,12 @@ function TBoldPersistenceControllerPassthrough.DatabaseInterface: IBoldDatabase;
     result := nil;
 end;
 
+destructor TBoldPersistenceControllerPassthrough.Destroy;
+begin
+  FreeAndNil(fSubscriber);
+  inherited;
+end;
+
 function TBoldPersistenceControllerPassthrough.getNextPersistenceController: TBoldPersistenceController;
 begin
   if Assigned(fNextPersistenceController) then
@@ -160,6 +180,13 @@ procedure TBoldPersistenceControllerPassthrough.SubscribeToPersistenceEvents(
   NextPersistenceController.SubscribeToPersistenceEvents(Subscriber, Events);
 end;
 
+procedure TBoldPersistenceControllerPassthrough.Receive(Originator: TObject; OriginalEvent: TBoldEvent;
+  RequestedEvent: TBoldRequestedEvent);
+begin
+  if Originator = fNextPersistenceController then
+    fNextPersistenceController := nil;
+end;
+
 procedure TBoldPersistenceControllerPassthrough.ReserveNewIds(ValueSpace: IBoldValueSpace; ObjectIdList: TBoldObjectIdList;
              TranslationList: TBoldIdTranslationList);
 begin