Strip out all WCF messaging stuff and start again

All of this was cobbled together copy-pasta. Lets try again
at desiging the communication properly now I've experimented a bit.

WpkgInstaller/IWpkgMessageCallbackHandlerContract.cs

-using System.ServiceModel;
-
-namespace WpkgInstaller
-{
-    public interface IWpkgMessageCallbackHandlerContract
-    {
-        [OperationContract(IsOneWay = true)]
-        void HandleResponse(WpkgMessageResponse response);
-
-        [OperationContract(IsOneWay = true)]
-        void HandleMessage(WpkgMessageState status);
-    }
-}

WpkgInstaller/IWpkgMessageRequestHandlerContract.cs

-using System.ServiceModel;
-
-namespace WpkgInstaller
-{
-    public delegate WpkgMessageRequestType WpkgEventCallbackHandler(object sender, WpkgMessageRequest e);
-
-    [ServiceContract(Namespace = "https://www.ch.cam.ac.uk/WpkgNotifier",
-                     SessionMode = SessionMode.Required,
-                     CallbackContract = typeof(IWpkgMessageCallbackHandlerContract))]
-    public interface IWpkgMessageRequestHandlerContract
-    {
-        [OperationContract(IsOneWay = true)]
-        void HandleMessage(WpkgMessageRequestType type);
-    }
-}

WpkgInstaller/WpkgInstaller.cs

@@ -34,7 +34,6 @@ namespace WpkgInstaller
         [DllImport("advapi32.dll", SetLastError = true)]
         private static extern bool SetServiceStatus(System.IntPtr handle, ref ServiceStatus serviceStatus);
 
-        private IWpkgMessageCallbackHandlerContract notifierCallbackHandler;
         public WpkgInstaller()
         {
             InitializeComponent();
@@ -88,14 +87,12 @@ namespace WpkgInstaller
 
         private void RunWpkgSync()
         {
-            notifierCallbackHandler.HandleMessage(WpkgMessageState.SYNCING);
             eventLog.WriteEntry("Starting sync", EventLogEntryType.Information);
             RunWpkgCommand("/synchronize");
         }
 
         private void RunWpkgQuery()
         {
-            notifierCallbackHandler.HandleMessage(WpkgMessageState.QUERYING);
             eventLog.WriteEntry("Starting query", EventLogEntryType.Information);
             RunWpkgCommand("/query:m");
         }
@@ -127,15 +124,13 @@ namespace WpkgInstaller
             process.BeginOutputReadLine();
             process.WaitForExit();
 
-            notifierCallbackHandler.HandleMessage(WpkgMessageState.IDLE);
-
             if(process.ExitCode == 0)
             {
-                notifierCallbackHandler.HandleMessage(WpkgMessageState.SUCCESS);
+                // notify clients of success
             }
             else
             {
-                notifierCallbackHandler.HandleMessage(WpkgMessageState.ERROR);
+                // notify clients of error
             }
             String msg = String.Format("wpkg command finished, with exit code {0}", process.ExitCode);
             eventLog.WriteEntry(msg, EventLogEntryType.Information);
@@ -146,8 +141,7 @@ namespace WpkgInstaller
         {
             if (e != null && e.Data != null)
             {
-                notifierCallbackHandler.HandleResponse(new WpkgMessageResponse(e.Data));
-                //eventLog.WriteEntry(e.Data, EventLogEntryType.Information);
+                // sent e.Data back to clients
             }
 
         }
@@ -170,15 +164,7 @@ namespace WpkgInstaller
         {
             try
             {
-                Uri BaseAddress = new Uri("net.pipe://localhost/www.ch.cam.ac.uk/WpkgNotifier");
-                NetNamedPipeBinding binding = new NetNamedPipeBinding();
-
-                WpkgInstallerMessageService svc = new WpkgInstallerMessageService();
-                ServiceHost SvcHost = new ServiceHost(svc, BaseAddress);
-                SvcHost.AddServiceEndpoint(typeof(IWpkgMessageRequestHandlerContract), binding, "");
-                SvcHost.Open();
-
-                (SvcHost.SingletonInstance as WpkgInstallerMessageService).WpkgEventCallback += new WpkgEventCallbackHandler(ProcessMessage);
+               // open message channel
             } 
             catch (Exception e)
             {
@@ -189,10 +175,6 @@ namespace WpkgInstaller
 
         private WpkgMessageRequestType ProcessMessage(object sender, WpkgMessageRequest e)
         {
-            if (notifierCallbackHandler == null)
-            {
-                notifierCallbackHandler = OperationContext.Current.GetCallbackChannel<IWpkgMessageCallbackHandlerContract>();
-            }
 
             eventLog.WriteEntry(string.Format("Got {0}", e.Type));
             switch(e.Type)

WpkgInstaller/WpkgInstaller.csproj

@@ -70,7 +70,6 @@
     <Reference Include="System.Xml" />
   </ItemGroup>
   <ItemGroup>
-    <Compile Include="IWpkgMessageCallbackHandlerContract.cs" />
     <Compile Include="ProjectInstaller.cs">
       <SubType>Component</SubType>
     </Compile>
@@ -85,8 +84,6 @@
     </Compile>
     <Compile Include="Program.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
-    <Compile Include="WpkgInstallerMessageService.cs" />
-    <Compile Include="IWpkgMessageRequestHandlerContract.cs" />
     <Compile Include="WpkgMessageRequest.cs" />
     <Compile Include="WpkgMessageResponse.cs" />
     <Compile Include="WpkgMessageState.cs" />

WpkgInstaller/WpkgInstallerMessageService.cs

-using System.ServiceModel;
-
-namespace WpkgInstaller
-{
-    [ServiceBehavior(InstanceContextMode = InstanceContextMode.Single)]
-    class WpkgInstallerMessageService : IWpkgMessageRequestHandlerContract
-    {
-        public event WpkgEventCallbackHandler WpkgEventCallback = delegate { return WpkgMessageRequestType.DONE; };
-
-        public void HandleMessage(WpkgMessageRequestType type)
-        {
-            WpkgEventCallback(this, new WpkgMessageRequest(type));
-        }
-    }
-}

WpkgNotifier/TrayNotifier.cs

@@ -8,10 +8,10 @@ using WpkgInstaller;
 
 namespace WpkgNotifier
 {
-    class TrayNotifier : ApplicationContext, IWpkgMessageCallbackHandlerContract
+    class TrayNotifier : ApplicationContext
     {
         private NotifyIcon notifyIcon;
-        private IWpkgMessageRequestHandlerContract messageChannel;
+        
         private EventLog eventLog;
         private WpkgMessageState state;
 
@@ -69,14 +69,7 @@ namespace WpkgNotifier
             eventLog.WriteEntry("Trying to open channel");
             try
             {
-                string address = "net.pipe://localhost/www.ch.cam.ac.uk/WpkgNotifier";
-
-                NetNamedPipeBinding binding = new NetNamedPipeBinding();
-                InstanceContext context = new InstanceContext(this);
-                DuplexChannelFactory<IWpkgMessageRequestHandlerContract> factory = new DuplexChannelFactory<IWpkgMessageRequestHandlerContract>(context, binding, address);
-
-                messageChannel = factory.CreateChannel();
-                eventLog.WriteEntry("channel created");
+                // this method should probably be 'RegisterWithService'
             }
             catch (Exception e)
             {
@@ -89,13 +82,13 @@ namespace WpkgNotifier
         void RequestSync(object sender, EventArgs e)
         {
             notifyIcon.ContextMenu.MenuItems[0].Enabled = false;
-            messageChannel.HandleMessage(WpkgMessageRequestType.DO_SYNC);
+            // send DO_SYNC request to server
         }
 
         void RequestQuery(object sender, EventArgs e)
         {
             notifyIcon.ContextMenu.MenuItems[0].Enabled = false;
-            messageChannel.HandleMessage(WpkgMessageRequestType.RUN_QUERY);
+            // send RUN_QUERY request to server
         }
 
         void ManageSoftware(object sender, EventArgs e)