feat: Internal logging now uses Serilog instead of log4net

src/Agent/NewRelic/Agent/Core/AgentInitializer.cs

@@ -26,7 +26,7 @@ private static class CallOnce
         {
             static CallOnce()
             {
-                // we must ensure that we hook up to ProcessExit and DomainUnload *before* log4net.  Otherwise we can't log anything during OnExit.
+                // we must ensure that we hook up to ProcessExit and DomainUnload *before* log initialization.  Otherwise we can't log anything during OnExit.
                 AppDomain.CurrentDomain.ProcessExit += (sender, args) => OnExit(sender, args);
                 AppDomain.CurrentDomain.DomainUnload += (sender, args) => OnExit(sender, args);
                 LoggerBootstrapper.Initialize();

src/Agent/NewRelic/Agent/Core/Config/Configuration.cs

@@ -1301,8 +1301,6 @@ public partial class configurationLog
 
         private bool auditLogField;
 
-        private System.Nullable<configurationLogFileLockingModel> fileLockingModelField;
-
         /// <summary>
         /// configurationLog class constructor
         /// </summary>
@@ -1381,42 +1379,6 @@ public bool auditLog
             }
         }
 
-        [System.Xml.Serialization.XmlAttributeAttribute()]
-        public configurationLogFileLockingModel fileLockingModel
-        {
-            get
-            {
-                if (this.fileLockingModelField.HasValue)
-                {
-                    return this.fileLockingModelField.Value;
-                }
-                else
-                {
-                    return default(configurationLogFileLockingModel);
-                }
-            }
-            set
-            {
-                this.fileLockingModelField = value;
-            }
-        }
-
-        [System.Xml.Serialization.XmlIgnoreAttribute()]
-        public bool fileLockingModelSpecified
-        {
-            get
-            {
-                return this.fileLockingModelField.HasValue;
-            }
-            set
-            {
-                if (value==false)
-                {
-                    this.fileLockingModelField = null;
-                }
-            }
-        }
-
         #region Clone method
         /// <summary>
         /// Create a clone of this configurationLog object

src/Agent/NewRelic/Agent/Core/Config/Configuration.xsd

@@ -347,19 +347,6 @@
                             </xs:annotation>
                         </xs:attribute>
 
-                        <xs:attribute name="fileLockingModel">
-                            <xs:annotation>
-                                <xs:documentation>
-                                    Controls how agent-produced log files are to be locked.	Experimental.
-                                </xs:documentation>
-                            </xs:annotation>
-                            <xs:simpleType>
-                                <xs:restriction base="xs:string">
-                                    <xs:enumeration value="exclusive"/>
-                                    <xs:enumeration value="minimal"/>
-                                </xs:restriction>
-                            </xs:simpleType>
-                        </xs:attribute>
                     </xs:complexType>
                 </xs:element>
 

src/Agent/NewRelic/Agent/Core/Config/ConfigurationLoader.cs

@@ -586,22 +586,6 @@ private string GetLogFileName()
             return "newrelic_agent_" + Strings.SafeFileName(name) + ".log";
         }
 
-        public bool FileLockingModelSpecified
-        {
-            get
-            {
-                return fileLockingModelSpecified;
-            }
-        }
-
-        public configurationLogFileLockingModel FileLockingModel
-        {
-            get
-            {
-                return fileLockingModel;
-            }
-        }
-
         public bool Console
         {
             get

src/Agent/NewRelic/Agent/Core/Config/ILogConfig.cs

@@ -9,9 +9,6 @@ public interface ILogConfig
 
         string GetFullLogFileName();
 
-        bool FileLockingModelSpecified { get; }
-        configurationLogFileLockingModel FileLockingModel { get; }
-
         bool Console { get; }
 
         bool IsAuditLogEnabled { get; }

src/Agent/NewRelic/Agent/Core/Configuration/ConfigurationService.cs

@@ -63,15 +63,8 @@ private void OnConfigurationDeserialized(ConfigurationDeserializedEvent configur
 
         private static void UpdateLogLevel(configuration localConfiguration)
         {
-            var hierarchy = log4net.LogManager.GetRepository(Assembly.GetCallingAssembly()) as log4net.Repository.Hierarchy.Hierarchy;
-            var logger = hierarchy.Root;
-
-            var logLevel = logger.Hierarchy.LevelMap[localConfiguration.LogConfig.LogLevel];
-            if (logLevel != null && logLevel != logger.Level)
-            {
-                Log.InfoFormat("The log level was updated to {0}", logLevel);
-                logger.Level = logLevel;
-            }
+            Log.InfoFormat("The log level was updated to {0}", localConfiguration.LogConfig.LogLevel);
+            LoggerBootstrapper.UpdateLoggingLevel(localConfiguration.LogConfig.LogLevel);
         }
 
         private void OnServerConfigurationUpdated(ServerConfigurationUpdatedEvent serverConfigurationUpdatedEvent)

src/Agent/NewRelic/Agent/Core/Core.csproj

@@ -37,9 +37,13 @@
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>
+    <PackageReference Include="Serilog" Version="2.12.0" />
+    <PackageReference Include="Serilog.Sinks.Async" Version="1.5.0" />
+    <PackageReference Include="Serilog.Sinks.Console" Version="4.1.0" />
+    <PackageReference Include="Serilog.Sinks.Debug" Version="2.0.0" />
+    <PackageReference Include="Serilog.Sinks.File" Version="5.0.0" />
     <PackageReference Include="System.ValueTuple" Version="4.5.0" />
     <PackageReference Include="ILRepack" Version="2.0.16" />
-    <PackageReference Include="log4net" Version="2.0.8" />
     <PackageReference Include="Newtonsoft.Json" Version="13.0.1" />
     <PackageReference Include="SharpZipLib" Version="1.3.3" />
   </ItemGroup>
@@ -56,6 +60,7 @@
     <PackageReference Include="Castle.Core" Version="3.3.0" />
     <PackageReference Include="Castle.Windsor" Version="3.3.0" />
     <PackageReference Include="System.Runtime.InteropServices.RuntimeInformation" Version="4.3.0" />
+    <PackageReference Include="Serilog.Sinks.EventLog" Version="3.1.0" />
   </ItemGroup>
 
   <ItemGroup Condition="'$(TargetFramework)' == 'netstandard2.0'">
@@ -79,11 +84,6 @@
     <Reference Include="System.Configuration" />
   </ItemGroup>
 
-  <ItemGroup>
-    <Compile Include="$(RootProjectDirectory)\src\Agent\Shared\SharedLog4NetRepository.cs">
-      <Link>Properties\SharedLog4NetRepository.cs</Link>
-    </Compile>
-  </ItemGroup>
   <ItemGroup>
     <Service Include="{508349b6-6b84-4df5-91f0-309beebad82d}" />
   </ItemGroup>
@@ -105,8 +105,13 @@
       <ILRepackInclude Include="@(PossibleRefsForILRepack)" Condition="'%(FileName)' == 'Castle.Core'" />
       <ILRepackInclude Include="@(PossibleRefsForILRepack)" Condition="'%(FileName)' == 'Castle.Windsor'" />
       <ILRepackInclude Include="@(PossibleRefsForILRepack)" Condition="'%(FileName)' == 'ICSharpCode.SharpZipLib'" />
-      <ILRepackInclude Include="@(PossibleRefsForILRepack)" Condition="'%(FileName)' == 'log4net'" />
       <ILRepackInclude Include="@(PossibleRefsForILRepack)" Condition="'%(FileName)' == 'Newtonsoft.Json'" />
+      <ILRepackInclude Include="@(PossibleRefsForILRepack)" Condition="'%(FileName)' == 'Serilog'" />
+      <ILRepackInclude Include="@(PossibleRefsForILRepack)" Condition="'%(FileName)' == 'Serilog.Sinks.Async'" />
+      <ILRepackInclude Include="@(PossibleRefsForILRepack)" Condition="'%(FileName)' == 'Serilog.Sinks.Console'" />
+      <ILRepackInclude Include="@(PossibleRefsForILRepack)" Condition="'%(FileName)' == 'Serilog.Sinks.Debug'" />
+      <ILRepackInclude Include="@(PossibleRefsForILRepack)" Condition="'%(FileName)' == 'Serilog.Sinks.EventLog'" />
+      <ILRepackInclude Include="@(PossibleRefsForILRepack)" Condition="'%(FileName)' == 'Serilog.Sinks.File'" />
       <ILRepackInclude Include="@(PossibleRefsForILRepack)" Condition="'%(FileName)' == 'System.ValueTuple'" />
       <ILRepackInclude Include="@(PossibleRefsForILRepack)" Condition="'%(FileName)' == 'System.Memory'" />
       <ILRepackInclude Include="@(PossibleRefsForILRepack)" Condition="'%(FileName)' == 'System.Runtime.CompilerServices.Unsafe'" />
@@ -120,14 +125,18 @@
       <ILRepackInclude Include="@(PossibleRefsForILRepack)" Condition="'%(FileName)' == 'Grpc.Net.Common'" />
       <ILRepackInclude Include="@(PossibleRefsForILRepack)" Condition="'%(FileName)' == 'Grpc.Net.Client'" />
       <ILRepackInclude Include="@(PossibleRefsForILRepack)" Condition="'%(FileName)' == 'Autofac'" />
-      <ILRepackInclude Include="@(PossibleRefsForILRepack)" Condition="'%(FileName)' == 'log4net'" />
       <ILRepackInclude Include="@(PossibleRefsForILRepack)" Condition="'%(FileName)' == 'Newtonsoft.Json'" />
+      <ILRepackInclude Include="@(PossibleRefsForILRepack)" Condition="'%(FileName)' == 'Serilog'" />
+      <ILRepackInclude Include="@(PossibleRefsForILRepack)" Condition="'%(FileName)' == 'Serilog.Sinks.Async'" />
+      <ILRepackInclude Include="@(PossibleRefsForILRepack)" Condition="'%(FileName)' == 'Serilog.Sinks.Console'" />
+      <ILRepackInclude Include="@(PossibleRefsForILRepack)" Condition="'%(FileName)' == 'Serilog.Sinks.Debug'" />
+      <ILRepackInclude Include="@(PossibleRefsForILRepack)" Condition="'%(FileName)' == 'Serilog.Sinks.File'" />
       <ILRepackInclude Include="@(PossibleRefsForILRepack)" Condition="'%(FileName)' == 'ICSharpCode.SharpZipLib'" />
     </ItemGroup>
 
     <PropertyGroup>
-      <ILRepackIncludeCount Condition="'$(TargetFramework)' == 'net462'">15</ILRepackIncludeCount>
-      <ILRepackIncludeCount Condition="'$(TargetFramework)' == 'netstandard2.0'">11</ILRepackIncludeCount>
+      <ILRepackIncludeCount Condition="'$(TargetFramework)' == 'net462'">20</ILRepackIncludeCount>
+      <ILRepackIncludeCount Condition="'$(TargetFramework)' == 'netstandard2.0'">15</ILRepackIncludeCount>
     </PropertyGroup>
 
     <Error Text="ILRepack of $(AssemblyName) ($(TargetFramework)) failed. A dependency is missing. Expected $(ILRepackIncludeCount) dependencies but found @(ILRepackInclude-&gt;Count())." Condition="@(ILRepackInclude-&gt;Count()) != $(ILRepackIncludeCount)" />

src/Agent/NewRelic/Agent/Core/Labels/LabelsService.cs

@@ -12,7 +12,7 @@ namespace NewRelic.Agent.Core.Labels
 {
     public class LabelsService : ILabelsService
     {
-        private static readonly log4net.ILog Log = log4net.LogManager.GetLogger(typeof(LabelsService));
+        private readonly Serilog.ILogger Log = Serilog.Log.Logger;
 
         private const int MaxLabels = 64;
         private const int MaxLength = 255;
@@ -45,18 +45,18 @@ private IEnumerable<Label> GetLabelsFromConfiguration()
                     .ToList();
 
                 if (labels.Count == MaxLabels)
-                    Log.WarnFormat("Maximum number of labels reached, some may have been dropped.");
+                    Log.Warning("Maximum number of labels reached, some may have been dropped.");
 
                 return labels;
             }
             catch (Exception exception)
             {
-                Log.WarnFormat("Failed to parse labels configuration string: {0}", exception);
+                Log.Warning("Failed to parse labels configuration string: {0}", exception);
                 return Enumerable.Empty<Label>();
             }
         }
 
-        private static Label CreateLabelFromString(string typeAndValueString)
+        private Label CreateLabelFromString(string typeAndValueString)
         {
             if (typeAndValueString == null)
                 throw new ArgumentNullException("typeAndValueString");
@@ -87,11 +87,11 @@ private static Label CreateLabelFromString(string typeAndValueString)
             return new Label(typeTruncated, valueTruncated);
         }
 
-        private static string Truncate(string value)
+        private string Truncate(string value)
         {
             var result = value.TruncateUnicodeStringByLength(MaxLength);
             if (result.Length != value.Length)
-                Log.WarnFormat("Truncated label key from {0} to {1}", value, result);
+                Log.Warning("Truncated label key from {0} to {1}", value, result);
 
             return result;
         }

src/Agent/NewRelic/Agent/Core/Logging/AuditLog.cs

@@ -5,15 +5,15 @@ namespace NewRelic.Agent.Core.Logging
 {
     public static class AuditLog
     {
-        private static readonly log4net.ILog Logger = log4net.LogManager.GetLogger(typeof(AuditLog));
-
         /// <summary>
         /// Logs <paramref name="message"/> at the AUDIT level, a custom log level that is not well-defined in popular logging providers like log4net. This log level should be used only as dictated by the security team to satisfy auditing requirements.
         /// </summary>
         public static void Log(string message)
         {
-            var auditLogLevel = LoggerBootstrapper.GetAuditLevel();
-            Logger.Logger.Log(typeof(AuditLog), auditLogLevel, message, null);
+            // create a logger that injects an Audit property that we can later filter on (see LoggerBootstrapper.IncludeOnlyAuditLog)
+            var auditLogger = Serilog.Log.ForContext(LogLevelExtensions.AuditLevel, LogLevelExtensions.AuditLevel);
+            // use Fatal log level to ensure audit log messages never get filtered due to level restrictions
+            auditLogger.Fatal(message);
         }
     }
 }

src/Agent/NewRelic/Agent/Core/Logging/CustomAuditLogTextFormatter.cs

@@ -0,0 +1,19 @@
+// Copyright 2020 New Relic, Inc. All rights reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+using System.IO;
+using Serilog.Events;
+using Serilog.Formatting;
+
+namespace NewRelic.Agent.Core
+{
+    class CustomAuditLogTextFormatter : ITextFormatter
+    {
+        public void Format(LogEvent logEvent, TextWriter output)
+        {
+            logEvent.Properties.TryGetValue("Message", out var message);
+
+            output.Write($"{logEvent.Timestamp.ToUniversalTime():yyyy-MM-dd HH:mm:ss,fff} NewRelic  AUDIT: {message}{output.NewLine}");
+        }
+    }
+}

src/Agent/NewRelic/Agent/Core/Logging/CustomTextFormatter.cs

@@ -0,0 +1,24 @@
+// Copyright 2020 New Relic, Inc. All rights reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+using System.IO;
+using Serilog.Events;
+using Serilog.Formatting;
+
+namespace NewRelic.Agent.Core
+{
+    class CustomTextFormatter : ITextFormatter
+    {
+        public void Format(LogEvent logEvent, TextWriter output)
+        {
+            // try to get process and thread id
+            logEvent.Properties.TryGetValue("pid", out var pid);
+            logEvent.Properties.TryGetValue("tid", out var tid);
+
+            // format matches the log4net format, but adds the Exception property (if present in the message as a separate property) to the end, after the newline
+            // if that's not desired, take the Exception property out and refactor calls to `Serilog.Log.Logger.LogXxxx(exception, message)` so the exception is
+            // formatted into the message 
+            output.Write($"{logEvent.Timestamp.ToUniversalTime():yyyy-MM-dd HH:mm:ss,fff} NewRelic {logEvent.Level.TranslateLogLevel(),6}: [pid: {pid?.ToString()}, tid: {tid?.ToString()}] {logEvent.MessageTemplate}{output.NewLine}{logEvent.Exception}");
+        }
+    }
+}

src/Agent/NewRelic/Agent/Core/Logging/InMemorySink.cs

@@ -0,0 +1,45 @@
+// Copyright 2020 New Relic, Inc. All rights reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+using System;
+using Serilog.Core;
+using Serilog.Events;
+using System.Collections.Concurrent;
+using System.Collections.Generic;
+
+namespace NewRelic.Agent.Core.Logging
+{
+    public class InMemorySink : ILogEventSink, IDisposable
+    {
+        private readonly ConcurrentQueue<LogEvent> _logEvents;
+
+        public InMemorySink()
+        {
+            _logEvents = new ConcurrentQueue<LogEvent>();
+        }
+
+        public void Emit(LogEvent logEvent)
+        {
+            _logEvents.Enqueue(logEvent);
+        }
+
+        public IEnumerable<LogEvent> LogEvents
+        {
+            get
+            {
+                return _logEvents;
+            }
+        }
+
+        public void Clear()
+        {
+            while (_logEvents.TryDequeue(out _))
+            { }
+        }
+
+        public void Dispose()
+        {
+            Clear();
+        }
+    }
+}