RIP IApplicationEventHandler

src/Umbraco.Core/Logging/WebProfilerComponent.cs

@@ -0,0 +1,55 @@
+using System;
+using System.Web;
+using Umbraco.Core.Components;
+
+namespace Umbraco.Core.Logging
+{
+    internal class WebProfilerComponent : UmbracoComponentBase, IUmbracoCoreComponent
+    {
+        // the profiler is too important to be composed in a component,
+        // it is composed first thing in WebRuntime.Compose - this component
+        // only initializes it if needed.
+        //
+        //public override void Compose(ServiceContainer container)
+        //{
+        //    container.RegisterSingleton<IProfiler, WebProfiler>();
+        //}
+
+        private WebProfiler _profiler;
+
+        public void Initialize(IProfiler profiler, IRuntimeState runtime)
+        {
+            // although registered in WebRuntime.Compose, ensure that we have
+            // not been replaced by another component, and we are still "the" profiler
+            _profiler = profiler as WebProfiler;
+            if (_profiler == null) return;
+
+            if (SystemUtilities.GetCurrentTrustLevel() < AspNetHostingPermissionLevel.High)
+            {
+                // if we don't have a high enough trust level we cannot bind to the events
+                LogHelper.Info<WebProfilerComponent>("Cannot install when the application is running in Medium trust.");
+            }
+            else if (runtime.Debug == false)
+            {
+                // only when debugging
+                LogHelper.Info<WebProfilerComponent>("Cannot install when the application is not running in debug mode.");
+            }
+            else
+            {
+                // bind to ApplicationInit - ie execute the application initialization for *each* application
+                // it would be a mistake to try and bind to the current application events
+                UmbracoApplicationBase.ApplicationInit += InitializeApplication;
+            }
+        }
+
+        private void InitializeApplication(object sender, EventArgs args)
+        {
+            var app = sender as HttpApplication;
+            if (app == null) return;
+
+            // for *each* application (this will run more than once)
+            app.BeginRequest += (s, a) => _profiler.UmbracoApplicationBeginRequest(s, a);
+            app.EndRequest += (s, a) => _profiler.UmbracoApplicationEndRequest(s, a);
+        }
+    }
+}