Fix: Exception during content rendering kills the self host process

src/Nancy.Hosting.Self.Tests/NancySelfHostFixture.cs

@@ -131,6 +131,7 @@ private static NancyHostWrapper CreateAndOpenSelfHost(INancyBootstrapper nancyBo
 				nancyBootstrapper,
 				BaseUri);
 
+
 			try
 			{
 				host.Start();
@@ -143,6 +144,23 @@ private static NancyHostWrapper CreateAndOpenSelfHost(INancyBootstrapper nancyBo
 			return new NancyHostWrapper(host);
 		}
 
+
+		[SkippableFact]
+		public void Should_be_able_to_recover_from_rendering_exception()
+		{
+			using (CreateAndOpenSelfHost())
+			{
+
+				var reader =
+					new StreamReader(WebRequest.Create(new Uri(BaseUri,"exception")).GetResponse().GetResponseStream());
+
+				var response = reader.ReadToEnd();
+
+				response.ShouldEqual("Content");
+			}
+		}
+
+
 		private class NancyHostWrapper : IDisposable
 		{
 			private readonly NancyHost host;

src/Nancy.Hosting.Self.Tests/TestModule.cs

@@ -1,4 +1,6 @@
-namespace Nancy.Hosting.Self.Tests
+using System;
+
+namespace Nancy.Hosting.Self.Tests
 {
     using System.IO;
 
@@ -19,6 +21,14 @@ public TestModule()
                 };
 
             Post["/rel"] = parameters => new StreamReader(Request.Body).ReadToEnd();
+
+        	Get["/exception"] = parameters => new Response() {Contents = s =>
+        	                                                             	{
+        	                                                             		var writer = new StreamWriter(s);
+																				writer.Write("Content");
+																				writer.Flush();
+																				throw new Exception("An error occured during content rendering");
+        	                                                             	}};
         }
     }
 }

src/Nancy.Hosting.Self/NancyHost.cs

@@ -184,12 +184,28 @@ private void GotCallback(IAsyncResult ar)
 
         private void Process(HttpListenerContext ctx)
         {
-            var nancyRequest = 
-                ConvertRequestToNancyRequest(ctx.Request);
+            try
+            {
 
-            using (var nancyContext = engine.HandleRequest(nancyRequest))
+                var nancyRequest = ConvertRequestToNancyRequest(ctx.Request);
+                using (var nancyContext = engine.HandleRequest(nancyRequest))
+                {
+
+                    try
+                    {
+                        ConvertNancyResponseToResponse(nancyContext.Response, ctx.Response);
+                    }
+                    catch (Exception ex)
+                    {
+                        nancyContext.Trace.TraceLog.WriteLog(s => s.AppendLine(string.Concat("[SelfHost] Exception while rendering response: ", ex)));
+                        //TODO - the content of the tracelog is not used in this case
+                    }
+                }
+            }
+            catch (Exception)
             {
-                ConvertNancyResponseToResponse(nancyContext.Response, ctx.Response);
+                //TODO -  this swallows the exception so that it doesn't kill the host
+                // pass it to the host process for handling by the caller ?
             }
         }
     }