NLog GlobalDiagnosticContext should be explictly added using ContextProperties

CHANGELOG.md

@@ -1,7 +1,8 @@
 # Changelog 
 
-### Version 2.6.0
+### Version 2.6.0-vNext
 - [NLog Flush should include async delay](https://github.com/Microsoft/ApplicationInsights-dotnet-logging/pull/176)
+- [NLog can include additional ContextProperties](https://github.com/Microsoft/ApplicationInsights-dotnet-logging/pull/183)
 
 ### Version 2.6.0-beta3
 - [NetStandard Support for TraceListener](https://github.com/Microsoft/ApplicationInsights-dotnet-logging/pull/166)

src/NLogTarget/ApplicationInsightsTarget.cs

@@ -18,13 +18,14 @@ namespace Microsoft.ApplicationInsights.NLogTarget
 
     using NLog;
     using NLog.Common;
+    using NLog.Config;
     using NLog.Targets;
 
     /// <summary>
     /// NLog Target that routes all logging output to the Application Insights logging framework.
     /// The messages will be uploaded to the Application Insights cloud service.
     /// </summary>
-    [Target("ApplicationInsightsTarget")]   
+    [Target("ApplicationInsightsTarget")]
     public sealed class ApplicationInsightsTarget : TargetWithLayout
     {
         private TelemetryClient telemetryClient;
@@ -43,6 +44,12 @@ public ApplicationInsightsTarget()
         /// </summary>
         public string InstrumentationKey { get; set; }
 
+        /// <summary>
+        /// Gets the array of custom attributes to be passed into the logevent context
+        /// </summary>
+        [ArrayParameter(typeof(TargetPropertyWithContext), "contextproperty")]
+        public IList<TargetPropertyWithContext> ContextProperties { get; } = new List<TargetPropertyWithContext>();
+
         /// <summary>
         /// Gets the logging controller we will be using.
         /// </summary>
@@ -78,8 +85,20 @@ internal void BuildPropertyBag(LogEventInfo logEvent, ITelemetry trace)
                 propertyBag.Add("UserStackFrameNumber", logEvent.UserStackFrameNumber.ToString(CultureInfo.InvariantCulture));
             }
 
-            this.LoadGlobalDiagnosticsContextProperties(propertyBag);
-            this.LoadLogEventProperties(logEvent, propertyBag);
+            for (int i = 0; i < this.ContextProperties.Count; ++i)
+            {
+                var contextProperty = this.ContextProperties[i];
+                if (!string.IsNullOrEmpty(contextProperty.Name))
+                {
+                    string propertyValue = contextProperty.Layout?.Render(logEvent);
+                    this.PopulatePropertyBag(propertyBag, contextProperty.Name, propertyValue);
+                }
+            }
+
+            if (logEvent.HasProperties)
+            {
+                this.LoadLogEventProperties(logEvent, propertyBag);
+            }
         }
 
         /// <summary>
@@ -165,7 +184,7 @@ private void SendException(LogEventInfo logEvent)
         private void SendTrace(LogEventInfo logEvent)
         {
             string logMessage = this.Layout.Render(logEvent);
-            
+
             var trace = new TraceTelemetry(logMessage)
             {
                 SeverityLevel = this.GetSeverityLevel(logEvent.Level)
@@ -175,20 +194,11 @@ private void SendTrace(LogEventInfo logEvent)
             this.telemetryClient.Track(trace);
         }
 
-        private void LoadGlobalDiagnosticsContextProperties(IDictionary<string, string> propertyBag)
-        {
-            foreach (string key in GlobalDiagnosticsContext.GetNames())
-            {
-                this.PopulatePropertyBag(propertyBag, key, GlobalDiagnosticsContext.GetObject(key));
-            }
-        }
-
         private void LoadLogEventProperties(LogEventInfo logEvent, IDictionary<string, string> propertyBag)
         {
-            var properties = logEvent.Properties;
-            if (properties != null)
+            if (logEvent.Properties?.Count > 0)
             {
-                foreach (var keyValuePair in properties)
+                foreach (var keyValuePair in logEvent.Properties)
                 {
                     string key = keyValuePair.Key.ToString();
                     object valueObj = keyValuePair.Value;
@@ -204,7 +214,7 @@ private void PopulatePropertyBag(IDictionary<string, string> propertyBag, string
                 return;
             }
 
-            string value = valueObj.ToString();
+            string value = Convert.ToString(valueObj, CultureInfo.InvariantCulture);
             if (propertyBag.ContainsKey(key))
             {
                 if (string.Equals(value, propertyBag[key], StringComparison.Ordinal))

src/NLogTarget/TargetPropertyWithContext.cs

@@ -0,0 +1,52 @@
+// -----------------------------------------------------------------------
+// <copyright file="ApplicationInsightsTarget.cs" company="Microsoft">
+// Copyright (c) Microsoft Corporation. 
+// All rights reserved.  2013
+// </copyright>
+// -----------------------------------------------------------------------
+
+namespace Microsoft.ApplicationInsights.NLogTarget
+{
+    using NLog.Config;
+    using NLog.Layouts;
+
+    /// <summary>
+    /// NLog Target Context Property that allows capture of context information for all logevents (Ex. Layout=${threadid})
+    /// </summary>
+    [NLogConfigurationItem]
+    [ThreadAgnostic]
+    public class TargetPropertyWithContext
+    {
+        /// <summary>
+        /// Initializes a new instance of the <see cref="TargetPropertyWithContext" /> class.
+        /// </summary>
+        public TargetPropertyWithContext() : this(null, null)
+        {
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="TargetPropertyWithContext" /> class.
+        /// </summary>
+        /// <param name="name">The name of the attribute.</param>
+        /// <param name="layout">The layout of the attribute's value.</param>
+        public TargetPropertyWithContext(string name, Layout layout)
+        {
+            this.Name = name;
+            this.Layout = layout;
+        }
+
+        /// <summary>
+        /// Gets or sets the name of the attribute.
+        /// </summary>
+        /// <docgen category='Property Options' order='10' />
+        [RequiredParameter]
+        public string Name { get; set; }
+
+        /// <summary>
+        /// Gets or sets the layout that will be rendered as the attribute's value.
+        /// </summary>
+        /// <docgen category='Property Options' order='10' />
+        [RequiredParameter]
+        public Layout Layout { get; set; }
+    }
+}

test/NLogTarget.Net45.Tests/NLogTargetTests.cs

@@ -62,7 +62,7 @@ public void InitializeTargetNotThrowsWhenInstrumentationKeyIsEmptyString()
                 Assert.Fail("Expected NLogConfigurationException but none was thrown with message:{0}", ex.Message);
             }
         }
-        
+
         [TestMethod]
         [TestCategory("NLogTarget")]
         public void ExceptionsDoNotEscapeNLog()
@@ -164,7 +164,7 @@ public void TraceMessageCanBeFormedUsingLayout()
             target.Layout = @"${uppercase:${level}} ${message}";
 
             Logger aiLogger = this.CreateTargetWithGivenInstrumentationKey("test", null, target);
-            
+
             aiLogger.Debug("Message");
 
             var telemetry = (TraceTelemetry)this.adapterHelper.Channel.SentItems.FirstOrDefault();
@@ -222,7 +222,9 @@ public void TraceHasCustomProperties()
         [TestCategory("NLogTarget")]
         public void GlobalDiagnosticContextPropertiesAreAddedToProperties()
         {
-            Logger aiLogger = this.CreateTargetWithGivenInstrumentationKey();
+            ApplicationInsightsTarget target = new ApplicationInsightsTarget();
+            target.ContextProperties.Add(new TargetPropertyWithContext("global_prop", "${gdc:item=global_prop}"));
+            Logger aiLogger = this.CreateTargetWithGivenInstrumentationKey(target: target);
 
             NLog.GlobalDiagnosticsContext.Set("global_prop", "global_value");
             aiLogger.Debug("Message");
@@ -235,7 +237,9 @@ public void GlobalDiagnosticContextPropertiesAreAddedToProperties()
         [TestCategory("NLogTarget")]
         public void GlobalDiagnosticContextPropertiesSupplementEventProperties()
         {
-            Logger aiLogger = this.CreateTargetWithGivenInstrumentationKey();
+            ApplicationInsightsTarget target = new ApplicationInsightsTarget();
+            target.ContextProperties.Add(new TargetPropertyWithContext("global_prop", "${gdc:item=global_prop}"));
+            Logger aiLogger = this.CreateTargetWithGivenInstrumentationKey(target: target);
 
             NLog.GlobalDiagnosticsContext.Set("global_prop", "global_value");
 
@@ -254,7 +258,9 @@ public void GlobalDiagnosticContextPropertiesSupplementEventProperties()
         public void EventPropertyKeyNameIsAppendedWith_1_IfSameAsGlobalDiagnosticContextKeyName()
 #pragma warning restore CA1707 // Identifiers should not contain underscores
         {
-            Logger aiLogger = this.CreateTargetWithGivenInstrumentationKey();
+            ApplicationInsightsTarget target = new ApplicationInsightsTarget();
+            target.ContextProperties.Add(new TargetPropertyWithContext("Name", "${gdc:item=Name}"));
+            Logger aiLogger = this.CreateTargetWithGivenInstrumentationKey(target: target);
 
             NLog.GlobalDiagnosticsContext.Set("Name", "Global Value");
             var eventInfo = new LogEventInfo(LogLevel.Trace, "TestLogger", "Hello!");
@@ -294,7 +300,7 @@ public void TraceAreEnqueuedInChannelAndContainExceptionMessage()
         public void CustomMessageIsAddedToExceptionTelemetryCustomProperties()
         {
             Logger aiLogger = this.CreateTargetWithGivenInstrumentationKey();
-            
+
             try
             {
                 throw new Exception("Test logging exception");
@@ -313,7 +319,7 @@ public void CustomMessageIsAddedToExceptionTelemetryCustomProperties()
         public void NLogTraceIsSentAsVerboseTraceItem()
         {
             var aiLogger = this.CreateTargetWithGivenInstrumentationKey("F8474271-D231-45B6-8DD4-D344C309AE69");
-            
+
             aiLogger.Trace("trace");
 
             var telemetry = (TraceTelemetry)this.adapterHelper.Channel.SentItems.FirstOrDefault();