Adding wrapper providers for lazy instantiation of the data provider.…

… Lazy, Deferred and Conditional DataProviders.

CHANGELOG.md

@@ -3,6 +3,9 @@ All notable changes to Audit.NET and its extensions will be documented in this f
 
 The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/).
 
+## [24.0.0] - 2024-:
+- Audit.NET: Adding wrapper providers to allow lazy instantiation of the data provider. LazyDataProvider, DeferredDataProvider and ConditionalDataProvider.
+
 ## [23.0.0] - 2023-12-13:
 - Beginning with version 23.0.0, this library and its extensions has discontinued support for older .NET Framework and Entity Framework (versions that lost Microsoft support before 2023).
 New minimum supported .NET framework versions are net462, netstandard2.0 & net6.0. (#637)

Directory.Build.props

@@ -1,6 +1,6 @@
 <Project>
  <PropertyGroup>
-	 <Version>23.0.0</Version>
+	 <Version>24.0.0</Version>
 	 <PackageReleaseNotes></PackageReleaseNotes>
 	 <CheckEolTargetFramework>false</CheckEolTargetFramework>
  </PropertyGroup>

src/Audit.NET.AmazonQLDB/Providers/AmazonQldbDataProvider.cs

@@ -82,7 +82,7 @@ public AmazonQldbDataProvider(Action<IAmazonQldbProviderConfigurator> config)
             }
         }
 
-        public override object Serialize<T>(T value)
+        public override object CloneValue<T>(T value, AuditEvent auditEvent)
         {
             if (value == null)
             {

src/Audit.NET.AzureCosmos/Providers/AzureCosmosDataProvider.DocumentDb.cs

@@ -105,7 +105,7 @@ public AzureCosmosDataProvider(Action<IAzureCosmosProviderConfigurator> config)
             IdBuilder = cosmosDbConfig._idBuilder;
         }
 
-        public override object Serialize<T>(T value)
+        public override object CloneValue<T>(T value, AuditEvent auditEvent)
         {
             if (value == null)
             {

src/Audit.NET.MongoDB/Providers/MongoDataProvider.cs

@@ -173,11 +173,11 @@ private void SerializeExtraFields(AuditEvent auditEvent)
         {
             foreach(var k in auditEvent.CustomFields.Keys.ToList())
             {
-                auditEvent.CustomFields[k] = Serialize(auditEvent.CustomFields[k]);
+                auditEvent.CustomFields[k] = CloneValue(auditEvent.CustomFields[k], auditEvent);
             }
         }
 
-        public override object Serialize<T>(T value)
+        public override object CloneValue<T>(T value, AuditEvent auditEvent)
         {
             if (value == null || value is string)
             {
@@ -199,7 +199,7 @@ public override object Serialize<T>(T value)
                 return value.ToBsonDocument(typeof(object));
             }
 
-            return base.Serialize(value);
+            return base.CloneValue(value, auditEvent);
         }
 
         protected virtual BsonDocument ParseBson(AuditEvent auditEvent)

src/Audit.NET.RavenDB/Providers/RavenDbDataProvider.cs

@@ -79,7 +79,7 @@ public RavenDbDataProvider(Action<IRavenDbProviderConfigurator> config)
             _documentStore.Initialize();
         }
 
-        public override object Serialize<T>(T value)
+        public override object CloneValue<T>(T value, AuditEvent auditEvent)
         {
             if (value == null)
             {

src/Audit.NET/Audit.NET.csproj

@@ -27,7 +27,7 @@
 
 	<ItemGroup>
 		<None Include="..\..\LICENSE" Pack="true" PackagePath="LICENSE" />
-		<None Include="..\..\README.md" Pack="true" PackagePath="\"/>
+		<None Include="..\..\README.md" Pack="true" PackagePath="\" />
 	</ItemGroup>
 
 	<ItemGroup>
@@ -45,7 +45,7 @@
 	</ItemGroup>
 
 	<ItemGroup>
-		<None Include="images\icon.png" Pack="true" PackagePath="\"/>
+		<None Include="images\icon.png" Pack="true" PackagePath="\" />
 	</ItemGroup>
 
 </Project>

src/Audit.NET/AuditDataProvider.cs

@@ -10,15 +10,18 @@ namespace Audit.Core
     public abstract class AuditDataProvider
     {
         /// <summary>
-        /// Override this method to provide a different serialization method for the values that need to be serialized before saving.
+        /// Override this method to provide a different cloning method for the values that need to be pre-serialized before saving.
         /// (old target value and custom fields)
         /// </summary>
-        public virtual object Serialize<T>(T value)
+        /// <param name="value">The value to clone</param>
+        /// <param name="auditEvent">The audit event associated to the value being serialized</param>
+        public virtual object CloneValue<T>(T value, AuditEvent auditEvent)
         {
             if (value == null)
             {
                 return null;
             }
+
             if (value is string)
             {
                 return value;

src/Audit.NET/AuditScope.cs

@@ -45,16 +45,18 @@ internal AuditScope(AuditScopeOptions options)
             {
                 _event.CustomFields = new Dictionary<string, object>();
             }
+
+            ProcessExtraFields(options.ExtraFields);
+
             if (options.TargetGetter != null)
             {
                 var targetValue = options.TargetGetter.Invoke();
                 _event.Target = new AuditTarget
                 {
-                    Old = _dataProvider.Serialize(targetValue),
+                    Old = _dataProvider.CloneValue(targetValue, _event),
                     Type = targetValue?.GetType().GetFullTypeName() ?? "Object"
                 };
             }
-            ProcessExtraFields(options.ExtraFields);
         }
 #endregion
 
@@ -140,7 +142,7 @@ public void SetTargetGetter(Func<object> targetGetter)
                 var targetValue = targetGetter.Invoke();
                 _event.Target = new AuditTarget
                 {
-                    Old = _dataProvider.Serialize(targetValue),
+                    Old = _dataProvider.CloneValue(targetValue, _event),
                     Type = targetValue?.GetType().GetFullTypeName() ?? "Object"
                 };
             }
@@ -175,10 +177,10 @@ public void Comment(string format, params object[] args)
         /// <typeparam name="TC">The type of the value.</typeparam>
         /// <param name="fieldName">Name of the field.</param>
         /// <param name="value">The value object.</param>
-        /// <param name="serialize">if set to <c>true</c> the field is serialized immediately.</param>
+        /// <param name="serialize">if set to <c>true</c> the value will be serialized immediately.</param>
         public void SetCustomField<TC>(string fieldName, TC value, bool serialize = false)
         {
-            _event.CustomFields[fieldName] = serialize ? _dataProvider.Serialize(value) : value;
+            _event.CustomFields[fieldName] = serialize ? _dataProvider.CloneValue(value, _event) : value;
         }
 
         /// <summary>
@@ -477,7 +479,7 @@ private void EndEvent()
             _event.Duration = Convert.ToInt32((_event.EndDate.Value - _event.StartDate).TotalMilliseconds);
             if (_targetGetter != null)
             {
-                _event.Target.New = _dataProvider.Serialize(_targetGetter.Invoke());
+                _event.Target.New = _dataProvider.CloneValue(_targetGetter.Invoke(), _event);
             }
         }
 

src/Audit.NET/AuditScopeOptions.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Reflection;
+using Audit.Core.Providers.Wrappers;
 
 namespace Audit.Core
 {
@@ -24,14 +25,17 @@ public class AuditScopeOptions
         public object ExtraFields { get; set; }
 
         /// <summary>
-        /// Gets or Sets the data provider builder.
+        /// Sets the data provider as a factory method that will be invoked the first time it's needed and only once. This is a shortcut to set a LazyDataProvider.
         /// </summary>
-        public Func<AuditDataProvider> DataProviderFactory { get; set; }
-
+        public Func<AuditDataProvider> DataProviderFactory 
+        {
+            set => DataProvider = new LazyDataProvider(value);
+        }
+
         /// <summary>
         /// Gets or sets the data provider to use.
         /// </summary>
-        public AuditDataProvider DataProvider { get { return DataProviderFactory?.Invoke(); } set { DataProviderFactory = () => value; } }
+        public AuditDataProvider DataProvider { get; set; }
 
         /// <summary>
         /// Gets or sets the event creation policy to use.
@@ -97,7 +101,7 @@ public AuditScopeOptions(
             TargetGetter = targetGetter;
             ExtraFields = extraFields;
             CreationPolicy = creationPolicy ?? Configuration.CreationPolicy;
-            DataProviderFactory = dataProvider != null ? () => dataProvider : Configuration.DataProviderFactory;
+            DataProvider = dataProvider ?? Configuration.DataProvider;
             IsCreateAndSave = isCreateAndSave;
             AuditEvent = auditEvent;
             SkipExtraFrames = skipExtraFrames;
@@ -126,7 +130,7 @@ public AuditScopeOptions(Action<IAuditScopeOptionsConfigurator> config)
                 TargetGetter = scopeConfig._options.TargetGetter;
                 ExtraFields = scopeConfig._options.ExtraFields;
                 CreationPolicy = scopeConfig._options.CreationPolicy;
-                DataProviderFactory = scopeConfig._options.DataProviderFactory;
+                DataProvider = scopeConfig._options.DataProvider;
                 IsCreateAndSave = scopeConfig._options.IsCreateAndSave;
                 AuditEvent = scopeConfig._options.AuditEvent;
                 SkipExtraFrames = scopeConfig._options.SkipExtraFrames;

src/Audit.NET/AuditScopeOptionsConfigurator.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Reflection;
+using Audit.Core.Providers.Wrappers;
 
 namespace Audit.Core
 {
@@ -31,12 +32,18 @@ public IAuditScopeOptionsConfigurator DataProvider(AuditDataProvider dataProvide
             return this;
         }
 
-        public IAuditScopeOptionsConfigurator DataProvider(Func<AuditDataProvider> dataProviderFactory)
+        public IAuditScopeOptionsConfigurator DataProviderLazyFactory(Func<AuditDataProvider> dataProviderFactory)
         {
             _options.DataProviderFactory = dataProviderFactory;
             return this;
         }
 
+        public IAuditScopeOptionsConfigurator DataProviderDeferredFactory(Func<AuditEvent, AuditDataProvider> dataProviderFactory)
+        {
+            _options.DataProvider = new DeferredDataProvider(dataProviderFactory);
+            return this;
+        }
+
         public IAuditScopeOptionsConfigurator EventType(string eventType)
         {
             _options.EventType = eventType;

src/Audit.NET/Configuration.cs

@@ -7,6 +7,7 @@
 using System.Threading.Tasks;
 using System.Text.Json;
 using System.Text.Json.Serialization;
+using Audit.Core.Providers.Wrappers;
 
 namespace Audit.Core
 {
@@ -26,20 +27,23 @@ public static class Configuration
         public static EventCreationPolicy CreationPolicy { get; set; }
 
         /// <summary>
-        /// Gets or Sets the Default data provider factory.
+        /// Sets the Default data provider as a factory method that will be invoked the first time it's needed and only once. This is a shortcut to set a LazyDataProvider.
         /// </summary>
-        public static Func<AuditDataProvider> DataProviderFactory { get; set; }
+        public static Func<AuditDataProvider> DataProviderFactory 
+        {
+            set => DataProvider = new LazyDataProvider(value);
+        }
 
         /// <summary>
         /// Gets or Sets the Default data provider instance.
         /// </summary>
-        public static AuditDataProvider DataProvider { get { return DataProviderFactory?.Invoke(); } set { DataProviderFactory = () => value; } }
+        public static AuditDataProvider DataProvider { get; set; }
 
         /// <summary>
         /// Gets the Default data provider instance as the specified type. Returns null if the data provider is not of the given type.
         /// </summary>
         /// <typeparam name="T">The AuditDataProvider type</typeparam>
-        public static T DataProviderAs<T>() where T : AuditDataProvider { return DataProviderFactory?.Invoke() as T; } 
+        public static T DataProviderAs<T>() where T : AuditDataProvider { return DataProvider as T; } 
 
         /// <summary>
         /// Gets or Sets a value that indicates if the logged Type Names should include the namespace. Default is false.

src/Audit.NET/ConfigurationApi/ConditionalDataProviderConfigurator.cs

@@ -0,0 +1,77 @@
+using System;
+using System.Collections.Generic;
+using Audit.Core.Providers.Wrappers;
+
+namespace Audit.Core.ConfigurationApi
+{
+    public class ConditionalDataProviderConfigurator : IConditionalDataProviderConfigurator
+    {
+        internal List<ConditionalDataProvider.GuardCondition> _guardConditions = new List<ConditionalDataProvider.GuardCondition>();
+
+        /// <inheritdoc />
+        public IConditionalDataProviderConfigurator When(Func<AuditEvent, bool> guardCondition, Func<AuditEvent, AuditDataProvider> dataProviderFactory)
+        {
+            _guardConditions.Add(new ConditionalDataProvider.GuardCondition()
+            {
+                Guard = guardCondition,
+                DataProvider = new DeferredDataProvider(dataProviderFactory)
+            });
+
+            return this;
+        }
+
+        /// <inheritdoc />
+        public IConditionalDataProviderConfigurator When(Func<AuditEvent, bool> guardCondition, Func<AuditDataProvider> dataProviderInitializer)
+        {
+            _guardConditions.Add(new ConditionalDataProvider.GuardCondition()
+            {
+                Guard = guardCondition,
+                DataProvider = new LazyDataProvider(dataProviderInitializer)
+            });
+
+            return this;
+        }
+
+        /// <inheritdoc />
+        public IConditionalDataProviderConfigurator When(Func<AuditEvent, bool> guardCondition, AuditDataProvider dataProvider)
+        {
+            _guardConditions.Add(new ConditionalDataProvider.GuardCondition()
+            {
+                Guard = guardCondition,
+                DataProvider = dataProvider
+            });
+
+            return this;
+        }
+
+        /// <inheritdoc />
+        public void Otherwise(Func<AuditEvent, AuditDataProvider> dataProviderFactory)
+        {
+            _guardConditions.Add(new ConditionalDataProvider.GuardCondition()
+            {
+                Guard = _ => true,
+                DataProvider = new DeferredDataProvider(dataProviderFactory)
+            });
+        }
+
+        /// <inheritdoc />
+        public void Otherwise(Func<AuditDataProvider> dataProviderInitializer)
+        {
+            _guardConditions.Add(new ConditionalDataProvider.GuardCondition()
+            {
+                Guard = _ => true,
+                DataProvider = new LazyDataProvider(dataProviderInitializer)
+            });
+        }
+
+        /// <inheritdoc />
+        public void Otherwise(AuditDataProvider dataProvider)
+        {
+            _guardConditions.Add(new ConditionalDataProvider.GuardCondition()
+            {
+                Guard = _ => true,
+                DataProvider = dataProvider
+            });
+        }
+    }
+}

src/Audit.NET/ConfigurationApi/Configurator.cs

@@ -1,5 +1,6 @@
 using System;
 using Audit.Core.Providers;
+using Audit.Core.Providers.Wrappers;
 
 namespace Audit.Core.ConfigurationApi
 {
@@ -45,15 +46,23 @@ public ICreationPolicyConfigurator Use(Action<IDynamicDataProviderConfigurator>
         {
             return UseDynamicProvider(config);
         }
-        public ICreationPolicyConfigurator UseFactory(Func<AuditDataProvider> dataProviderFactory)
+        public ICreationPolicyConfigurator UseDeferredFactory(Func<AuditEvent, AuditDataProvider> dataProviderFactory)
         {
-            Configuration.DataProviderFactory = dataProviderFactory;
+            Configuration.DataProvider = new DeferredDataProvider(dataProviderFactory);
             return new CreationPolicyConfigurator();
         }
-        public ICreationPolicyConfigurator Use(Func<AuditDataProvider> dataProviderFactory)
+        public ICreationPolicyConfigurator UseLazyFactory(Func<AuditDataProvider> dataProviderInitializer)
         {
-            return UseFactory(dataProviderFactory);
+            Configuration.DataProvider = new LazyDataProvider(dataProviderInitializer);
+            return new CreationPolicyConfigurator();
+        }
+
+        public ICreationPolicyConfigurator UseConditional(Action<IConditionalDataProviderConfigurator> config)
+        {
+            Configuration.DataProvider = new ConditionalDataProvider(config);
+            return new CreationPolicyConfigurator();
         }
+
         public ICreationPolicyConfigurator Use(AuditDataProvider provider)
         {
             return UseCustomProvider(provider);