--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/OrthancStone/UnitTestsSources/TestMessageBroker.cpp	Wed Jan 12 08:23:38 2022 +0100
@@ -0,0 +1,106 @@
+/**
+ * Stone of Orthanc
+ * Copyright (C) 2012-2016 Sebastien Jodogne, Medical Physics
+ * Department, University Hospital of Liege, Belgium
+ * Copyright (C) 2017-2022 Osimis S.A., Belgium
+ * Copyright (C) 2021-2022 Sebastien Jodogne, ICTEAM UCLouvain, Belgium
+ *
+ * This program is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public License
+ * as published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this program. If not, see
+ * <http://www.gnu.org/licenses/>.
+ **/
+
+
+#include <gtest/gtest.h>
+
+#include "../Sources/Messages/IObservable.h"
+#include "../Sources/Messages/ObserverBase.h"
+
+
+int testCounter = 0;
+namespace {
+
+  using namespace OrthancStone;
+
+
+  class MyObservable : public IObservable
+  {
+  public:
+    struct MyCustomMessage : public IMessage
+    {
+      ORTHANC_STONE_MESSAGE(__FILE__, __LINE__);
+
+      int payload_;
+
+      MyCustomMessage(int payload) :
+        payload_(payload)
+      {
+      }
+    };
+  };
+
+  class MyObserver : public ObserverBase<MyObserver>
+  {
+  public:
+    void HandleCompletedMessage(const MyObservable::MyCustomMessage& message)
+    {
+      testCounter += message.payload_;
+    }
+  };
+}
+
+
+TEST(MessageBroker, TestPermanentConnectionSimpleUseCase)
+{
+  MyObservable  observable;
+  boost::shared_ptr<MyObserver>  observer(new MyObserver);
+
+  // create a permanent connection between an observable and an observer
+  observer->Register<MyObservable::MyCustomMessage>(observable, &MyObserver::HandleCompletedMessage);
+
+  testCounter = 0;
+  observable.BroadcastMessage(MyObservable::MyCustomMessage(12));
+  ASSERT_EQ(12, testCounter);
+
+  // the connection is permanent; if we emit the same message again, the observer will be notified again
+  testCounter = 0;
+  observable.BroadcastMessage(MyObservable::MyCustomMessage(20));
+  ASSERT_EQ(20, testCounter);
+
+  // Unregister the observer; make sure it's not called anymore
+  observer.reset();
+  testCounter = 0;
+  observable.BroadcastMessage(MyObservable::MyCustomMessage(20));
+  ASSERT_EQ(0, testCounter);
+}
+
+TEST(MessageBroker, TestPermanentConnectionDeleteObserver)
+{
+  MyObservable  observable;
+  boost::shared_ptr<MyObserver>  observer(new MyObserver);
+
+  // create a permanent connection between an observable and an observer
+  observer->Register<MyObservable::MyCustomMessage>(observable, &MyObserver::HandleCompletedMessage);
+
+  testCounter = 0;
+  observable.BroadcastMessage(MyObservable::MyCustomMessage(12));
+  ASSERT_EQ(12, testCounter);
+
+  // delete the observer and check that the callback is not called anymore
+  observer.reset();
+
+  // the connection is permanent; if we emit the same message again, the observer will be notified again
+  testCounter = 0;
+  observable.BroadcastMessage(MyObservable::MyCustomMessage(20));
+  ASSERT_EQ(0, testCounter);
+}