Record request logs and exception stack (#42)

sample/SkyWalking.Sample.Backend/Controllers/ErrorsController.cs

+using System;
+using Microsoft.AspNetCore.Mvc;
+
+namespace SkyWalking.Sample.Backend.Controllers
+{
+    [Route("api/[controller]")]
+    public class ErrorsController :Controller
+    {
+        public string Get()
+        {
+            throw new InvalidOperationException("error sample.");
+        }
+    }
+}
\ No newline at end of file

src/SkyWalking.AspNetCore/Diagnostics/HostingDiagnosticProcessor.cs

@@ -17,7 +17,10 @@
  */
 
 using System;
+using System.Collections.Generic;
 using Microsoft.AspNetCore.Http;
+using Microsoft.AspNetCore.Http.Extensions;
+using Microsoft.AspNetCore.Mvc.Abstractions;
 using SkyWalking.Context;
 using SkyWalking.Context.Tag;
 using SkyWalking.Context.Trace;
@@ -31,46 +34,86 @@ namespace SkyWalking.AspNetCore.Diagnostics
         public string ListenerName { get; } = "Microsoft.AspNetCore";
 
         [DiagnosticName("Microsoft.AspNetCore.Hosting.BeginRequest")]
-        public void BeginRequest([Property]HttpContext httpContext)
+        public void BeginRequest([Property] HttpContext httpContext)
         {
             var carrier = new ContextCarrier();
             foreach (var item in carrier.Items)
                 item.HeadValue = httpContext.Request.Headers[item.HeadKey];
-
             var httpRequestSpan = ContextManager.CreateEntrySpan(httpContext.Request.Path, carrier);
             httpRequestSpan.AsHttp();
             httpRequestSpan.SetComponent(ComponentsDefine.AspNetCore);
             Tags.Url.Set(httpRequestSpan, httpContext.Request.Path);
             Tags.HTTP.Method.Set(httpRequestSpan, httpContext.Request.Method);
+            httpRequestSpan.Log(DateTimeOffset.UtcNow.ToUnixTimeMilliseconds(),
+                new Dictionary<string, object>
+                {
+                    {"event", "AspNetCore Hosting BeginRequest"},
+                    {"message", $"Request starting {httpContext.Request.Protocol} {httpContext.Request.Method} {httpContext.Request.GetDisplayUrl()}"}
+                });
+            httpContext.Items[HttpContextDiagnosticStrings.SpanKey] = httpRequestSpan;
         }
 
         [DiagnosticName("Microsoft.AspNetCore.Hosting.EndRequest")]
-        public void EndRequest([Property]HttpContext httpContext)
+        public void EndRequest([Property] HttpContext httpContext)
         {
             var httpRequestSpan = ContextManager.ActiveSpan;
             if (httpRequestSpan == null)
             {
                 return;
             }
+
             var statusCode = httpContext.Response.StatusCode;
             if (statusCode >= 400)
             {
                 httpRequestSpan.ErrorOccurred();
             }
+
             Tags.StatusCode.Set(httpRequestSpan, statusCode.ToString());
+            httpRequestSpan.Log(DateTimeOffset.UtcNow.ToUnixTimeMilliseconds(),
+                new Dictionary<string, object>
+                {
+                    {"event", "AspNetCore Hosting EndRequest"},
+                    {"message", $"Request finished {httpContext.Response.StatusCode} {httpContext.Response.ContentType}"}
+                });
             ContextManager.StopSpan(httpRequestSpan);
         }
 
         [DiagnosticName("Microsoft.AspNetCore.Diagnostics.UnhandledException")]
-        public void DiagnosticUnhandledException(HttpContext httpContext, Exception exception)
+        public void DiagnosticUnhandledException([Property]HttpContext httpContext, [Property]Exception exception)
         {
-            ContextManager.ActiveSpan.ErrorOccurred();
+            ContextManager.ActiveSpan?.ErrorOccurred()?.Log(exception);
         }
 
         [DiagnosticName("Microsoft.AspNetCore.Hosting.UnhandledException")]
         public void HostingUnhandledException([Property]HttpContext httpContext, [Property]Exception exception)
         {
-            ContextManager.ActiveSpan.ErrorOccurred();
+            ContextManager.ActiveSpan?.ErrorOccurred()?.Log(exception);
+        }
+        
+        [DiagnosticName("Microsoft.AspNetCore.Mvc.BeforeAction")]
+        public void BeforeAction([Property]ActionDescriptor actionDescriptor, [Property]HttpContext httpContext)
+        {
+            var span = httpContext.Items[HttpContextDiagnosticStrings.SpanKey] as ISpan;
+            if (span == null)
+            {
+                return;
+            }
+
+            var events = new Dictionary<string, object> {{"event", "AspNetCore.Mvc Executing action method"}, {"Action method", actionDescriptor.DisplayName}};
+            span.Log(DateTimeOffset.UtcNow.ToUnixTimeMilliseconds(), events);
+        }
+
+        [DiagnosticName("Microsoft.AspNetCore.Mvc.AfterAction")]
+        public void AfterAction([Property]ActionDescriptor actionDescriptor, [Property]HttpContext httpContext)
+        {
+            var span = httpContext.Items[HttpContextDiagnosticStrings.SpanKey] as ISpan;
+            if (span == null)
+            {
+                return;
+            }
+
+            var events = new Dictionary<string, object> {{"event", "AspNetCore.Mvc Executed action method"}};
+            span.Log(DateTimeOffset.UtcNow.ToUnixTimeMilliseconds(), events);
         }
     }
 }
\ No newline at end of file

src/SkyWalking.AspNetCore/Diagnostics/HttpContextDiagnosticStrings.cs

+/*
+ * Licensed to the OpenSkywalking under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+namespace SkyWalking.AspNetCore.Diagnostics
+{
+    internal static class HttpContextDiagnosticStrings
+    {
+        public const string SpanKey = "sw3-http";
+    }
+}
\ No newline at end of file