Com events

AtlFreeServer/AtlFreeServer.vcxproj

@@ -146,6 +146,14 @@
       <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">NotUsing</PrecompiledHeader>
       <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Release|x64'">NotUsing</PrecompiledHeader>
     </ClCompile>
+    <ClCompile Include="..\Build\Output\Include\Interfaces\IListener_i.c">
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">NotUsing</PrecompiledHeader>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Release|x64'">NotUsing</PrecompiledHeader>
+    </ClCompile>
+    <ClCompile Include="..\Build\Output\Include\Interfaces\IListener_p.c">
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">NotUsing</PrecompiledHeader>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Release|x64'">NotUsing</PrecompiledHeader>
+    </ClCompile>
     <ClCompile Include="GuardDog.cpp" />
     <ClCompile Include="pch.cpp">
       <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">Create</PrecompiledHeader>

Interfaces/IListener.idl

@@ -0,0 +1,14 @@
+import "oaidl.idl";
+import "ocidl.idl";
+
+[
+	oleautomation,
+	object,
+	uuid(2E2944D8-CD27-45ED-ADAB-9644C87CE6B8),
+	pointer_default(unique)
+]
+interface IListener : IUnknown
+{
+	HRESULT Start([in] IUnknown* toListen);
+	HRESULT Stop();
+};

Interfaces/IPetShop.idl

@@ -19,4 +19,16 @@ interface IPetShop : IUnknown
 {
 	HRESULT BuyDog([out, retval] IDog** dog);
 	HRESULT GetAddress([out, retval] Address* address);
-};
+	HRESULT Open();
+};
+
+[
+	uuid(A8545F26-9028-46DB-9D89-A7B395B3260F)
+]
+dispinterface _DPetShopEvents
+{
+	properties:
+	methods:
+	[id(1)]
+	void Opened();
+};

Interfaces/Interfaces.idl

@@ -5,6 +5,7 @@ import "IHen.idl";
 import "IDog.idl";
 import "IPostman.idl";
 import "IPetShop.idl";
+import "IListener.idl";
 
 [
 	uuid(8edbf75d-ecf2-4a1f-affc-07fcb8dee00a),
@@ -18,5 +19,7 @@ library Interfaces
 	interface IDog;
 	interface IPostman;
 	interface IPetShop;
+	interface IListener;
+	dispinterface _DPetShopEvents;
 };
 

Interfaces/interfaces.vcxproj

@@ -11,6 +11,7 @@
     </ProjectConfiguration>
   </ItemGroup>
   <ItemGroup>
+    <Midl Include="IListener.idl" />
     <Midl Include="IRoyalPython.idl" />
     <Midl Include="IHen.idl" />
     <Midl Include="Interfaces.idl" />

Interfaces/interfaces.vcxproj.filters

@@ -7,6 +7,7 @@
     <Midl Include="IPostman.idl" />
     <Midl Include="IPetShop.idl" />
     <Midl Include="IRoyalPython.idl" />
+    <Midl Include="IListener.idl" />
   </ItemGroup>
   <ItemGroup>
     <None Include="readme.md" />

ManagedServer/PetShop.cs

@@ -6,9 +6,14 @@ namespace ManagedServer
 {
     [Guid("5011c315-994d-49b4-b737-03a846f590a0")]
     [ProgId("ManagedServer.PetShop.1")]
+    [ComSourceInterfaces(typeof(_DPetShopEvents))]
     [ComVisible(true)]
     public class PetShop : IPetShop
     {
+        public delegate void Opened_Delegate();
+
+        private event Opened_Delegate Opened;
+
         public PetShop()
         {
 
@@ -27,5 +32,10 @@ public Address GetAddress()
             address.City = "Oslo";
             return address;
         }
+
+        public void Open()
+        {
+            Opened?.Invoke();
+        }
     }
 }

TutorialsAndTests/Tests/ManagedServerTests.cpp

@@ -1,9 +1,14 @@
 #include "../pch.h"
 #include <gtest/gtest.h>
+#include <Interfaces/Interfaces.h>
+#include <Interfaces/IListener.h>
 #include <Interfaces/IDog.h>
 #include <Interfaces/IPetShop.h>
 #include <ComUtility/Utility.h>
 #include <wrl.h>
+#include <atlbase.h>
+#include <atlcom.h>
+#include <atlcomcli.h>
 
 using Microsoft::WRL::ComPtr;
 
@@ -57,4 +62,100 @@ TEST(ManagedServerTests,
     SysFreeString(address.Street);
     SysFreeString(address.PostalCode);
     SysFreeString(address.City);
-}
+}
+
+// Base class to listen events from COM event source
+template<unsigned Id, typename Class, typename Events>
+struct ListenerImpl :
+    IDispEventSimpleImpl<Id, Class, &__uuidof(Events)>,
+    IListener
+{
+    // Connect to toListen event source
+    HRESULT Start(IUnknown* toListen) override
+    {
+        m_toListen = toListen;
+        // Setup the connection with the event source
+        DispEventAdvise(m_toListen);
+
+        return S_OK;
+    }
+
+    // Disconnect from event source
+    HRESULT Stop() override
+    {
+        // Break the connection with the event source
+        DispEventUnadvise(m_toListen);
+
+        // Release the application
+        m_toListen.Release();
+
+        return S_OK;
+    }
+
+protected:
+    CComPtr<IUnknown> m_toListen;
+};
+
+// Interface to add call expectations
+struct IEventsHandler
+{
+    virtual ~IEventsHandler() = default;
+    virtual void OnOpenedImpl() const = 0;
+};
+
+_ATL_FUNC_INFO OnOpenedInfo = { CC_STDCALL, VT_EMPTY, 0 };
+
+// Real PetShopListener, inspired from :
+// https://github.com/microsoft/VCSamples/blob/9e1d4475555b76a17a3568369867f1d7b6cc6126/VC2008Samples/ATL/General/ATLEventHandling/Simple.h
+struct PetShopListener :
+    CComObjectRootEx<CComMultiThreadModel>,
+    CComCoClass<PetShopListener>,
+    ListenerImpl<1, PetShopListener, _DPetShopEvents>,
+    IEventsHandler
+{
+    BEGIN_COM_MAP(PetShopListener)
+        COM_INTERFACE_ENTRY(IListener)
+    END_COM_MAP()
+
+    void __stdcall OnOpened()
+    {
+        OnOpenedImpl();
+    }
+
+    MOCK_METHOD(void, OnOpenedImpl, (), (const override));
+
+    BEGIN_SINK_MAP(PetShopListener)
+        SINK_ENTRY_INFO(/*nID =*/ 1, __uuidof(_DPetShopEvents), /*dispid =*/ 1, OnOpened, &OnOpenedInfo)
+    END_SINK_MAP()
+};
+
+TEST(ManagedServerTests,
+    RequireThat_Open_TriggersOpenedEvent_WhenCalled)
+{
+    CLSID petShopClsid{};
+    HR(CLSIDFromString(L"{5011c315-994d-49b4-b737-03a846f590a0}", &petShopClsid));
+
+    // Create managed PetShop what can Raise events
+    ATL::CComPtr<IPetShop> petShop;
+    HR(CoCreateInstance(petShopClsid, nullptr, CLSCTX_INPROC_SERVER, __uuidof(IPetShop), reinterpret_cast<void**>(&petShop)));
+    EXPECT_NE(petShop, nullptr);
+
+    // Create local instance for PetShopListener
+    auto petShopListener = make_self<PetShopListener>();
+
+    // Subscribe to the petShop events
+    petShopListener->Start(petShop);
+
+    // We expect that OnOpenedImpl called while we subscribed
+    EXPECT_CALL(*petShopListener, OnOpenedImpl())
+        .Times(1);
+
+    // Raise Opened event, this should call PetShopListener::OnOpened
+    petShop->Open();
+
+    // Unsubscribe from the petShop events
+    petShopListener->Stop();
+
+    // Raise Opened event, but no Listeners and PetShopListener::OnOpened is not called
+    petShop->Open();
+}