chore: Use logging source generators

Signed-off-by: Austin Drenski <[email protected]>

build/Common.props

@@ -1,6 +1,6 @@
 <Project>
   <PropertyGroup>
-    <LangVersion>7.3</LangVersion>
+    <LangVersion>latest</LangVersion>
     <EnforceCodeStyleInBuild>true</EnforceCodeStyleInBuild>
     <EnableNETAnalyzers>true</EnableNETAnalyzers>
   </PropertyGroup>
@@ -19,12 +19,13 @@
       Please sort alphabetically.
       Refer to https://docs.microsoft.com/nuget/concepts/package-versioning for semver syntax.
     -->
-    <MicrosoftExtensionsLoggerVer>[2.0,)</MicrosoftExtensionsLoggerVer>
+    <MicrosoftExtensionsLoggerVer>[8.0.0,)</MicrosoftExtensionsLoggerVer>
     <MicrosoftSourceLinkGitHubPkgVer>[1.0.0,2.0)</MicrosoftSourceLinkGitHubPkgVer>
   </PropertyGroup>
 
   <ItemGroup>
     <PackageReference Include="System.Collections.Immutable" Version="[1.7.1,)" />
     <PackageReference Include="System.Threading.Channels" Version="[6.0.0,)" />
+    <PackageReference Include="System.ValueTuple" Version="[4.5.0,)" Condition="'$(TargetFramework)' == 'net462'" />
   </ItemGroup>
 </Project>

src/OpenFeature/Api.cs

@@ -227,7 +227,7 @@ public void RemoveHandler(ProviderEventTypes type, EventHandlerDelegate handler)
         /// <param name="logger">The logger to be used</param>
         public void SetLogger(ILogger logger)
         {
-            this.EventExecutor.Logger = logger;
+            this.EventExecutor.SetLogger(logger);
         }
     }
 }

src/OpenFeature/EventExecutor.cs

@@ -13,7 +13,7 @@ namespace OpenFeature
 
     internal delegate Task ShutdownDelegate();
 
-    internal class EventExecutor
+    internal sealed partial class EventExecutor
     {
         private readonly object _lockObj = new object();
         public readonly Channel<object> EventChannel = Channel.CreateBounded<object>(1);
@@ -27,16 +27,18 @@ internal class EventExecutor
         private readonly Dictionary<ProviderEventTypes, List<EventHandlerDelegate>> _apiHandlers = new Dictionary<ProviderEventTypes, List<EventHandlerDelegate>>();
         private readonly Dictionary<string, Dictionary<ProviderEventTypes, List<EventHandlerDelegate>>> _clientHandlers = new Dictionary<string, Dictionary<ProviderEventTypes, List<EventHandlerDelegate>>>();
 
-        internal ILogger Logger { get; set; }
+        private ILogger _logger;
 
         public EventExecutor()
         {
-            this.Logger = new Logger<EventExecutor>(new NullLoggerFactory());
+            this._logger = NullLogger<EventExecutor>.Instance;
             this._shutdownDelegate = this.SignalShutdownAsync;
             var eventProcessing = new Thread(this.ProcessEventAsync);
             eventProcessing.Start();
         }
 
+        internal void SetLogger(ILogger logger) => this._logger = logger;
+
         internal void AddApiLevelHandler(ProviderEventTypes eventType, EventHandlerDelegate handler)
         {
             lock (this._lockObj)
@@ -218,7 +220,7 @@ private void EmitOnRegistration(FeatureProviderReference provider, ProviderEvent
                 }
                 catch (Exception exc)
                 {
-                    this.Logger?.LogError("Error running handler: " + exc);
+                    this.ErrorRunningHandler(exc);
                 }
             }
         }
@@ -323,7 +325,7 @@ private void InvokeEventHandler(EventHandlerDelegate eventHandler, Event e)
             }
             catch (Exception exc)
             {
-                this.Logger?.LogError("Error running handler: " + exc);
+                this.ErrorRunningHandler(exc);
             }
         }
 
@@ -346,6 +348,9 @@ private async Task SignalShutdownAsync()
             // Wait for the processing loop to acknowledge the shutdown
             await this._shutdownSemaphore.WaitAsync().ConfigureAwait(false);
         }
+
+        [LoggerMessage(100, LogLevel.Error, "Error running handler")]
+        partial void ErrorRunningHandler(Exception exception);
     }
 
     internal class ShutdownSignal

src/OpenFeature/OpenFeatureClient.cs

@@ -15,7 +15,7 @@ namespace OpenFeature
     /// <summary>
     ///
     /// </summary>
-    public sealed class FeatureClient : IFeatureClient
+    public sealed partial class FeatureClient : IFeatureClient
     {
         private readonly ClientMetadata _metadata;
         private readonly ConcurrentStack<Hook> _hooks = new ConcurrentStack<Hook>();
@@ -76,7 +76,7 @@ public void SetContext(EvaluationContext context)
         public FeatureClient(string name, string version, ILogger logger = null, EvaluationContext context = null)
         {
             this._metadata = new ClientMetadata(name, version);
-            this._logger = logger ?? new Logger<Api>(new NullLoggerFactory());
+            this._logger = logger ?? NullLogger<Api>.Instance;
             this._evaluationContext = context ?? EvaluationContext.Empty;
         }
 
@@ -233,15 +233,14 @@ private async Task<FlagEvaluationDetails<T>> EvaluateFlag<T>(
             }
             catch (FeatureProviderException ex)
             {
-                this._logger.LogError(ex, "Error while evaluating flag {FlagKey}. Error {ErrorType}", flagKey,
-                    ex.ErrorType.GetDescription());
+                this.FlagEvaluationErrorWithDescription(flagKey, ex.ErrorType.GetDescription(), ex);
                 evaluation = new FlagEvaluationDetails<T>(flagKey, defaultValue, ex.ErrorType, Reason.Error,
                     string.Empty, ex.Message);
                 await this.TriggerErrorHooks(allHooksReversed, hookContext, ex, options).ConfigureAwait(false);
             }
             catch (Exception ex)
             {
-                this._logger.LogError(ex, "Error while evaluating flag {FlagKey}", flagKey);
+                this.FlagEvaluationError(flagKey, ex);
                 var errorCode = ex is InvalidCastException ? ErrorType.TypeMismatch : ErrorType.General;
                 evaluation = new FlagEvaluationDetails<T>(flagKey, defaultValue, errorCode, Reason.Error, string.Empty);
                 await this.TriggerErrorHooks(allHooksReversed, hookContext, ex, options).ConfigureAwait(false);
@@ -270,8 +269,7 @@ private async Task<HookContext<T>> TriggerBeforeHooks<T>(IReadOnlyList<Hook> hoo
                 }
                 else
                 {
-                    this._logger.LogDebug("Hook {HookName} returned null, nothing to merge back into context",
-                        hook.GetType().Name);
+                    this.HookReturnedNull(hook.GetType().Name);
                 }
             }
 
@@ -298,7 +296,7 @@ private async Task TriggerErrorHooks<T>(IReadOnlyList<Hook> hooks, HookContext<T
                 }
                 catch (Exception e)
                 {
-                    this._logger.LogError(e, "Error while executing Error hook {0}", hook.GetType().Name);
+                    this.ErrorHookError(hook.GetType().Name, e);
                 }
             }
         }
@@ -314,9 +312,24 @@ private async Task TriggerFinallyHooks<T>(IReadOnlyList<Hook> hooks, HookContext
                 }
                 catch (Exception e)
                 {
-                    this._logger.LogError(e, "Error while executing Finally hook {0}", hook.GetType().Name);
+                    this.FinallyHookError(hook.GetType().Name, e);
                 }
             }
         }
+
+        [LoggerMessage(100, LogLevel.Debug, "Hook {HookName} returned null, nothing to merge back into context")]
+        partial void HookReturnedNull(string hookName);
+
+        [LoggerMessage(101, LogLevel.Error, "Error while evaluating flag {FlagKey}")]
+        partial void FlagEvaluationError(string flagKey, Exception exception);
+
+        [LoggerMessage(102, LogLevel.Error, "Error while evaluating flag {FlagKey}: {ErrorType}")]
+        partial void FlagEvaluationErrorWithDescription(string flagKey, string errorType, Exception exception);
+
+        [LoggerMessage(103, LogLevel.Error, "Error while executing Error hook {HookName}")]
+        partial void ErrorHookError(string hookName, Exception exception);
+
+        [LoggerMessage(104, LogLevel.Error, "Error while executing Finally hook {HookName}")]
+        partial void FinallyHookError(string hookName, Exception exception);
     }
 }

test/OpenFeature.Tests/OpenFeatureClientTests.cs

@@ -6,7 +6,6 @@
 using AutoFixture;
 using FluentAssertions;
 using Microsoft.Extensions.Logging;
-using Microsoft.Extensions.Logging.Internal;
 using NSubstitute;
 using NSubstitute.ExceptionExtensions;
 using OpenFeature.Constant;
@@ -183,9 +182,9 @@ public async Task OpenFeatureClient_Should_Return_DefaultValue_When_Type_Mismatc
             mockedLogger.Received(1).Log(
                 LogLevel.Error,
                 Arg.Any<EventId>(),
-                Arg.Is<FormattedLogValues>(t => string.Equals($"Error while evaluating flag {flagName}", t.ToString(), StringComparison.InvariantCultureIgnoreCase)),
+                Arg.Is<string>(t => string.Equals($"Error while evaluating flag {flagName}", t.ToString(), StringComparison.InvariantCultureIgnoreCase)),
                 Arg.Any<Exception>(),
-                Arg.Any<Func<object, Exception, string>>());
+                Arg.Any<Func<string, Exception, string>>());
         }
 
         [Fact]