Merge pull request #27 from petemounce/headers

Add ability to render Headers

NLog.Web.Tests/LayoutRenderers/AspNetRequestValueLayoutRendererTests.cs

@@ -112,6 +112,53 @@ public void KeyFoundRendersValue()
             }
         }
 
+        public class HeaderTests
+        {
+            [Fact]
+            public void NullKeyRendersEmptyString()
+            {
+                var httpContext = Substitute.For<HttpContextBase>();
+
+                var renderer = new AspNetRequestValueLayoutRenderer();
+                renderer.HttpContextAccessor = new FakeHttpContextAccessor(httpContext);
+                renderer.Header = null;
+
+                var result = renderer.Render(new LogEventInfo());
+
+                Assert.Empty(result);
+            }
+
+            [Fact]
+            public void KeyNotFoundRendersEmptyString()
+            {
+                var httpContext = Substitute.For<HttpContextBase>();
+
+                var renderer = new AspNetRequestValueLayoutRenderer();
+                renderer.HttpContextAccessor = new FakeHttpContextAccessor(httpContext);
+                renderer.Header = "key";
+
+                var result = renderer.Render(new LogEventInfo());
+
+                Assert.Empty(result);
+            }
+
+            [Fact]
+            public void KeyFoundRendersValue()
+            {
+                var expectedResult = "value";
+                var httpContext = Substitute.For<HttpContextBase>();
+                httpContext.Request.Headers.Returns(new NameValueCollection { { "key", expectedResult } });
+
+                var renderer = new AspNetRequestValueLayoutRenderer();
+                renderer.HttpContextAccessor = new FakeHttpContextAccessor(httpContext);
+                renderer.Header = "key";
+
+                var result = renderer.Render(new LogEventInfo());
+
+                Assert.Equal(expectedResult, result);
+            }
+        }
+
         public class FormTests
         {
             [Fact]

NLog.Web.Tests/LayoutRenderers/AspNetSessionValueLayoutRendererTests.cs

@@ -1,7 +1,4 @@
 using System;
-using System.Collections.Generic;
-using System.IO;
-using System.Linq;
 using System.Reflection;
 using System.Web;
 using System.Web.SessionState;
@@ -12,10 +9,8 @@
 
 namespace NLog.Web.Tests.LayoutRenderers
 {
-    public class AspNetSessionValueLayoutRendererTests : IDisposable
+    public class AspNetSessionValueLayoutRendererTests : TestInvolvingAspNetHttpContext
     {
-
-
         public AspNetSessionValueLayoutRendererTests()
         {
             SetUp();
@@ -26,9 +21,8 @@ public void SetUp()
             SetupFakeSession();
         }
 
-        public void CleanUp()
+        protected override void CleanUp()
         {
-
             Session.Clear();
         }
 
@@ -216,35 +210,19 @@ private void ExecTest(string key, object value, object expected, LayoutRenderer
         /// <summary>
         /// Create Fake Session http://stackoverflow.com/a/10126711/201303
         /// </summary>
-        public static void SetupFakeSession()
+        public void SetupFakeSession()
         {
-            var httpRequest = new HttpRequest("", "http://stackoverflow/", "");
-            var stringWriter = new StringWriter();
-            var httpResponse = new HttpResponse(stringWriter);
-            var httpContext = new HttpContext(httpRequest, httpResponse);
-
             var sessionContainer = new HttpSessionStateContainer("id", new SessionStateItemCollection(),
                                                     new HttpStaticObjectsCollection(), 10, true,
                                                     HttpCookieMode.AutoDetect,
                                                     SessionStateMode.InProc, false);
 
-            httpContext.Items["AspSession"] = typeof(HttpSessionState).GetConstructor(
+            HttpContext.Items["AspSession"] = typeof(HttpSessionState).GetConstructor(
                                         BindingFlags.NonPublic | BindingFlags.Instance,
                                         null, CallingConventions.Standard,
                                         new[] { typeof(HttpSessionStateContainer) },
                                         null)
                                 .Invoke(new object[] { sessionContainer });
-
-            HttpContext.Current = httpContext;
-
-        }
-
-        /// <summary>
-        /// Performs application-defined tasks associated with freeing, releasing, or resetting unmanaged resources.
-        /// </summary>
-        public void Dispose()
-        {
-            CleanUp();
         }
     }
 }

NLog.Web.Tests/LayoutRenderers/TestInvolvingAspNetHttpContext.cs

@@ -0,0 +1,66 @@
+using System;
+using System.Collections;
+using System.IO;
+using System.Reflection;
+using System.Web;
+
+namespace NLog.Web.Tests.LayoutRenderers
+{
+    public abstract class TestInvolvingAspNetHttpContext : IDisposable
+    {
+        protected HttpContext HttpContext;
+
+        protected TestInvolvingAspNetHttpContext()
+        {
+            HttpContext = SetupFakeHttpContext();
+            HttpContext.Current = HttpContext;
+        }
+
+        /// <summary>
+        ///     Performs application-defined tasks associated with freeing, releasing, or resetting unmanaged resources.
+        /// </summary>
+        public void Dispose()
+        {
+            CleanUp();
+        }
+
+        protected virtual void CleanUp()
+        {
+        }
+
+        protected HttpContext SetupFakeHttpContext()
+        {
+            var httpRequest = SetUpHttpRequest();
+            var stringWriter = new StringWriter();
+            var httpResponse = new HttpResponse(stringWriter);
+            return new HttpContext(httpRequest, httpResponse);
+        }
+
+        protected virtual HttpRequest SetUpHttpRequest(string query = "")
+        {
+            return new HttpRequest("", "http://stackoverflow/", query);
+        }
+
+        protected void AddHeader(HttpRequest request, string headerName, string headerValue)
+        {
+            // thanks http://stackoverflow.com/a/13307238
+            var headers = request.Headers;
+            var t = headers.GetType();
+            var item = new ArrayList();
+
+            t.InvokeMember("MakeReadWrite", BindingFlags.InvokeMethod | BindingFlags.NonPublic | BindingFlags.Instance,
+                null,
+                headers, null);
+            t.InvokeMember("InvalidateCachedArrays",
+                BindingFlags.InvokeMethod | BindingFlags.NonPublic | BindingFlags.Instance,
+                null, headers, null);
+            item.Add(headerValue);
+            t.InvokeMember("BaseAdd", BindingFlags.InvokeMethod | BindingFlags.NonPublic | BindingFlags.Instance, null,
+                headers,
+                new object[] {headerName, item});
+            t.InvokeMember("MakeReadOnly", BindingFlags.InvokeMethod | BindingFlags.NonPublic | BindingFlags.Instance,
+                null,
+                headers, null);
+        }
+    }
+}

NLog.Web.Tests/NLog.Web.Tests.csproj

@@ -84,6 +84,7 @@
     <Compile Include="LayoutRenderers\AspNetSessionIDLayoutRendererTests.cs" />
     <Compile Include="LayoutRenderers\AspNetSessionValueLayoutRendererTests.cs" />
     <Compile Include="LayoutRenderers\AspNetUserAuthTypeLayoutRendererTests.cs" />
+    <Compile Include="LayoutRenderers\TestInvolvingAspNetHttpContext.cs" />
     <Compile Include="LayoutRenderers\AspNetUserIdentityLayoutRendererTests.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
   </ItemGroup>

NLog.Web/LayoutRenderers/AspNetRequestValueLayoutRenderer.cs

@@ -19,6 +19,7 @@ namespace NLog.Web.LayoutRenderers
     /// ${aspnet-request:querystring=v}
     /// ${aspnet-request:form=v}
     /// ${aspnet-request:cookie=v}
+    /// ${aspnet-request:header=h}
     /// ${aspnet-request:serverVariable=v}
     /// </code>
     /// </example>
@@ -56,6 +57,12 @@ public class AspNetRequestValueLayoutRenderer : AspNetLayoutRendererBase
         /// <docgen category='Rendering Options' order='10' />
         public string ServerVariable { get; set; }
 
+        /// <summary>
+        /// Gets or sets the Headers item to be rendered.
+        /// </summary>
+        /// <docgen category='Rendering Options' order='10' />
+        public string Header { get; set; }
+
         /// <summary>
         /// Renders the specified ASP.NET Request variable and appends it to the specified <see cref="StringBuilder" />.
         /// </summary>
@@ -91,6 +98,15 @@ protected override void DoAppend(StringBuilder builder, LogEventInfo logEvent)
             {
                 builder.Append(httpRequest.ServerVariables[this.ServerVariable]);
             }
+            else if (this.Header != null)
+            {
+                string header = httpRequest.Headers[this.Header];
+
+                if (header != null)
+                {
+                    builder.Append(header);
+                }
+            }
             else if (this.Item != null)
             {
                 builder.Append(httpRequest[this.Item]);