Ensure ForeverFrameTransport throws if frameId is not a number

- Added a test to verify the exception when not a number which required making InitializeResponse protected internal
- #1446

src/Microsoft.AspNet.SignalR.Core/Resources.resx

@@ -156,6 +156,9 @@
   <data name="Error_HubInvocationFailed" xml:space="preserve">
     <value>There was an error invoking Hub method '{0}.{1}'.</value>
   </data>
+  <data name="Error_InvalidForeverFrameId" xml:space="preserve">
+    <value>The supplied frameId is in the incorrect format.</value>
+  </data>
   <data name="Error_IsNotA" xml:space="preserve">
     <value>'{0}' is not a {1}.</value>
   </data>

src/Microsoft.AspNet.SignalR.Core/Transports/ForeverFrameTransport.cs

@@ -1,6 +1,8 @@
 // Copyright (c) Microsoft Open Technologies, Inc. All rights reserved. See License.md in the project root for license information.
 
+using System;
 using System.Diagnostics.CodeAnalysis;
+using System.Globalization;
 using System.IO;
 using System.Text;
 using System.Threading.Tasks;
@@ -91,8 +93,15 @@ public override Task Send(PersistentResponse response)
             });
         }
 
-        protected override Task InitializeResponse(ITransportConnection connection)
+        protected internal override Task InitializeResponse(ITransportConnection connection)
         {
+            int frameId;
+            if (!Int32.TryParse(Context.Request.QueryString["frameId"], out frameId))
+            {
+                // Invalid frameId passed in
+                throw new InvalidOperationException(Resources.Error_InvalidForeverFrameId);
+            }
+
             return base.InitializeResponse(connection)
                 .Then(initScript =>
                 {
@@ -106,7 +115,7 @@ protected override Task InitializeResponse(ITransportConnection connection)
                         return Context.Response.Flush();
                     });
                 },
-                _initPrefix + Context.Request.QueryString["frameId"] + _initSuffix);
+                _initPrefix + frameId.ToString(CultureInfo.InvariantCulture) + _initSuffix);
         }
 
         private class HTMLTextWriter : StreamWriter

src/Microsoft.AspNet.SignalR.Core/Transports/ForeverTransport.cs

@@ -168,7 +168,7 @@ public virtual Task Send(object value)
             });
         }
 
-        protected virtual Task InitializeResponse(ITransportConnection connection)
+        protected internal virtual Task InitializeResponse(ITransportConnection connection)
         {
             return TaskAsyncHelper.Empty;
         }

src/Microsoft.AspNet.SignalR.Core/Transports/ServerSentEventsTransport.cs

@@ -48,7 +48,7 @@ public override Task Send(PersistentResponse response)
             });
         }
 
-        protected override Task InitializeResponse(ITransportConnection connection)
+        protected internal override Task InitializeResponse(ITransportConnection connection)
         {
             return base.InitializeResponse(connection)
                        .Then(() =>

tests/Microsoft.AspNet.SignalR.Tests/Core/Transports/ForeverFrameTransportFacts.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Specialized;
 using System.IO;
 using System.Threading;
 using System.Threading.Tasks;
@@ -24,6 +25,20 @@ public void ForeverFrameTransportEscapesTags()
             AssertEscaped(fft, response, "<p>ELLO</p>", "\\u003cp\\u003eELLO\\u003c/p\\u003e");
         }
 
+        [Fact]
+        public void ForeverFrameTransportThrowsOnInvalidFrameId()
+        {
+            var request = new Mock<IRequest>();
+            var qs = new NameValueCollection { { "frameId", "invalid" } };
+            request.Setup(r => r.QueryString).Returns(qs);
+            var response = new CustomResponse();
+            var context = new HostContext(request.Object, response);
+            var connection = new Mock<ITransportConnection>();
+            var fft = new ForeverFrameTransport(context, new DefaultDependencyResolver());
+
+            Assert.Throws(typeof(InvalidOperationException), () => fft.InitializeResponse(connection.Object));
+        }
+
         private static void AssertEscaped(ForeverFrameTransport fft, CustomResponse response, string input, string expectedOutput)
         {
             fft.Send(input).Wait();