Use ITargetingContext when calling GetVariantAsync

src/Microsoft.FeatureManagement/FeatureManager.cs

@@ -225,10 +225,10 @@ public async ValueTask<Variant> GetVariantAsync(string feature, CancellationToke
         /// Gets the assigned variant for a specific feature.
         /// </summary>
         /// <param name="feature">The name of the feature to evaluate.</param>
-        /// <param name="context">An instance of <see cref="TargetingContext"/> used to evaluate which variant the user will be assigned.</param>
+        /// <param name="context">A context providing information that can used to evaluate which variant the user will be assigned.</param>
         /// <param name="cancellationToken">The cancellation token to cancel the operation.</param>
         /// <returns>A variant assigned to the user based on the feature's configured allocation.</returns>
-        public async ValueTask<Variant> GetVariantAsync(string feature, TargetingContext context, CancellationToken cancellationToken = default)
+        public async ValueTask<Variant> GetVariantAsync<TContext>(string feature, TContext context, CancellationToken cancellationToken = default)
         {
             if (string.IsNullOrEmpty(feature))
             {
@@ -262,11 +262,11 @@ private async ValueTask<EvaluationEvent> EvaluateFeature<TContext>(string featur
 
             //
             // Determine Targeting Context
-            TargetingContext targetingContext;
+            ITargetingContext targetingContext;
 
             if (useContext)
             {
-                targetingContext = context as TargetingContext;
+                targetingContext = context as ITargetingContext;
             }
             else
             {
@@ -601,7 +601,7 @@ private async ValueTask<TargetingContext> ResolveTargetingContextAsync(Cancellat
             return context;
         }
 
-        private ValueTask<VariantDefinition> AssignVariantAsync(EvaluationEvent evaluationEvent, TargetingContext targetingContext, CancellationToken cancellationToken)
+        private ValueTask<VariantDefinition> AssignVariantAsync(EvaluationEvent evaluationEvent, ITargetingContext targetingContext, CancellationToken cancellationToken)
         {
             Debug.Assert(evaluationEvent != null);
 

src/Microsoft.FeatureManagement/FeatureManagerSnapshot.cs

@@ -97,7 +97,7 @@ public async ValueTask<Variant> GetVariantAsync(string feature, CancellationToke
             return variant;
         }
 
-        public async ValueTask<Variant> GetVariantAsync(string feature, TargetingContext context, CancellationToken cancellationToken)
+        public async ValueTask<Variant> GetVariantAsync<TContext>(string feature, TContext context, CancellationToken cancellationToken)
         {
             string cacheKey = GetVariantCacheKey(feature);
 

src/Microsoft.FeatureManagement/IVariantFeatureManager.cs

@@ -49,9 +49,9 @@ public interface IVariantFeatureManager
         /// Gets the assigned variant for a specific feature.
         /// </summary>
         /// <param name="feature">The name of the feature to evaluate.</param>
-        /// <param name="context">An instance of <see cref="TargetingContext"/> used to evaluate which variant the user will be assigned.</param>
+        /// <param name="context">A context providing information that can used to evaluate which variant the user will be assigned.</param>
         /// <param name="cancellationToken">The cancellation token to cancel the operation.</param>
         /// <returns>A variant assigned to the user based on the feature's configured allocation.</returns>
-        ValueTask<Variant> GetVariantAsync(string feature, TargetingContext context, CancellationToken cancellationToken = default);
+        ValueTask<Variant> GetVariantAsync<TContext>(string feature, TContext context, CancellationToken cancellationToken = default);
     }
 }

src/Microsoft.FeatureManagement/Telemetry/EvaluationEvent.cs

@@ -18,7 +18,7 @@ public class EvaluationEvent
         /// <summary>
         /// The targeting context used to evaluate the feature.
         /// </summary>
-        public TargetingContext TargetingContext { get; set; }
+        public ITargetingContext TargetingContext { get; set; }
 
         /// <summary>
         /// The enabled state of the feature after evaluation.

src/Microsoft.FeatureManagement/VariantFeatureManagerExtensions.cs

@@ -0,0 +1,28 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+//
+using Microsoft.FeatureManagement.FeatureFilters;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace Microsoft.FeatureManagement
+{
+    /// <summary>
+    /// Extensions used to provide an overload for <see cref="IVariantFeatureManager.GetVariantAsync"/> that accepts a <see cref="TargetingContext"/> type directly.
+    /// </summary>
+    public static class VariantFeatureManagerExtensions
+    {
+        /// <summary>
+        /// Gets the assigned variant for a specific feature.
+        /// </summary>
+        /// <param name="variantFeatureManager">The <see cref="IVariantFeatureManager"/> instance.</param>
+        /// <param name="feature">The name of the feature to evaluate.</param>
+        /// <param name="context">An instance of <see cref="TargetingContext"/> used to evaluate which variant the user will be assigned.</param>
+        /// <param name="cancellationToken">The cancellation token to cancel the operation.</param>
+        /// <returns>A variant assigned to the user based on the feature's configured allocation.</returns>
+        public static ValueTask<Variant> GetVariantAsync(this IVariantFeatureManager variantFeatureManager, string feature, TargetingContext context, CancellationToken cancellationToken = default)
+        {
+            return variantFeatureManager.GetVariantAsync(feature, context, cancellationToken);
+        }
+    }
+}