Add outcome to the break duration generator arguments

src/Polly.Core/CircuitBreaker/BreakDurationGeneratorArguments.cs

@@ -7,31 +7,31 @@ namespace Polly.CircuitBreaker;
 /// <summary>
 /// Represents arguments used to generate a dynamic break duration for a circuit breaker.
 /// </summary>
-public readonly struct BreakDurationGeneratorArguments
+/// <typeparam name="TResult">The type of result.</typeparam>
+public readonly struct BreakDurationGeneratorArguments<TResult>
 {
     /// <summary>
-    /// Initializes a new instance of the <see cref="BreakDurationGeneratorArguments"/> struct.
+    /// Initializes a new instance of the <see cref="BreakDurationGeneratorArguments{TResult}"/> struct.
     /// </summary>
     /// <param name="failureRate">The failure rate at which the circuit breaker should trip.
     /// It represents the ratio of failed actions to the total executed actions.</param>
     /// <param name="failureCount">The number of failures that have occurred.
     /// This count is used to determine if the failure threshold has been reached.</param>
     /// <param name="context">The resilience context providing additional information
     /// about the execution state and failures.</param>
+    /// <param name="outcome">The outcome of the resilience operation or event.</param>
     [EditorBrowsable(EditorBrowsableState.Never)]
     public BreakDurationGeneratorArguments(
         double failureRate,
         int failureCount,
-        ResilienceContext context)
+        ResilienceContext context,
+        Outcome<TResult> outcome)
+        : this(failureRate, failureCount, context, 0, outcome)
     {
-        FailureRate = failureRate;
-        FailureCount = failureCount;
-        Context = context;
-        HalfOpenAttempts = 0;
     }
 
     /// <summary>
-    /// Initializes a new instance of the <see cref="BreakDurationGeneratorArguments"/> struct.
+    /// Initializes a new instance of the <see cref="BreakDurationGeneratorArguments{TResult}"/> struct.
     /// </summary>
     /// <param name="failureRate">The failure rate at which the circuit breaker should trip.
     /// It represents the ratio of failed actions to the total executed actions.</param>
@@ -40,16 +40,19 @@ public BreakDurationGeneratorArguments(
     /// <param name="context">The resilience context providing additional information
     /// about the execution state and failures.</param>
     /// <param name="halfOpenAttempts">The number of half-open attempts.</param>
+    /// <param name="outcome">The outcome of the resilience operation or event.</param>
     public BreakDurationGeneratorArguments(
         double failureRate,
         int failureCount,
         ResilienceContext context,
-        int halfOpenAttempts)
+        int halfOpenAttempts,
+        Outcome<TResult> outcome)
     {
         FailureRate = failureRate;
         FailureCount = failureCount;
         Context = context;
         HalfOpenAttempts = halfOpenAttempts;
+        Outcome = outcome;
     }
 
     /// <summary>
@@ -71,4 +74,9 @@ public BreakDurationGeneratorArguments(
     /// Gets the number of half-open attempts.
     /// </summary>
     public int HalfOpenAttempts { get; }
+
+    /// <summary>
+    /// Gets the outcome of the user-specified callback.
+    /// </summary>
+    public Outcome<TResult> Outcome { get; }
 }

src/Polly.Core/CircuitBreaker/CircuitBreakerStrategyOptions.TResult.cs

@@ -75,7 +75,7 @@ public class CircuitBreakerStrategyOptions<TResult> : ResilienceStrategyOptions
     /// <value>
     /// The default value is <see langword="null"/>.
     /// </value>
-    public Func<BreakDurationGeneratorArguments, ValueTask<TimeSpan>>? BreakDurationGenerator { get; set; }
+    public Func<BreakDurationGeneratorArguments<TResult>, ValueTask<TimeSpan>>? BreakDurationGenerator { get; set; }
 
     /// <summary>
     /// Gets or sets a predicate that determines whether the outcome should be handled by the circuit breaker.

src/Polly.Core/CircuitBreaker/Controller/CircuitStateController.cs

@@ -16,7 +16,7 @@ internal sealed class CircuitStateController<T> : IDisposable
     private readonly ResilienceStrategyTelemetry _telemetry;
     private readonly CircuitBehavior _behavior;
     private readonly TimeSpan _breakDuration;
-    private readonly Func<BreakDurationGeneratorArguments, ValueTask<TimeSpan>>? _breakDurationGenerator;
+    private readonly Func<BreakDurationGeneratorArguments<T>, ValueTask<TimeSpan>>? _breakDurationGenerator;
     private DateTimeOffset _blockedUntil;
     private CircuitState _circuitState = CircuitState.Closed;
     private Outcome<T>? _lastOutcome;
@@ -33,7 +33,7 @@ public CircuitStateController(
         CircuitBehavior behavior,
         TimeProvider timeProvider,
         ResilienceStrategyTelemetry telemetry,
-        Func<BreakDurationGeneratorArguments, ValueTask<TimeSpan>>? breakDurationGenerator)
+        Func<BreakDurationGeneratorArguments<T>, ValueTask<TimeSpan>>? breakDurationGenerator)
 #pragma warning restore S107
     {
         _breakDuration = breakDuration;
@@ -323,7 +323,7 @@ private void OpenCircuitFor_NeedsLock(Outcome<T> outcome, TimeSpan breakDuration
         {
 #pragma warning disable CA2012
 #pragma warning disable S1226
-            breakDuration = _breakDurationGenerator(new(_behavior.FailureRate, _behavior.FailureCount, context, _halfOpenAttempts)).GetAwaiter().GetResult();
+            breakDuration = _breakDurationGenerator(new(_behavior.FailureRate, _behavior.FailureCount, context, _halfOpenAttempts, outcome)).GetAwaiter().GetResult();
 #pragma warning restore S1226
 #pragma warning restore CA2012
         }

src/Polly.Core/PublicAPI.Shipped.txt

@@ -11,14 +11,15 @@ override Polly.Registry.ResiliencePipelineRegistry<TKey>.TryGetPipeline(TKey key
 override Polly.Registry.ResiliencePipelineRegistry<TKey>.TryGetPipeline<TResult>(TKey key, out Polly.ResiliencePipeline<TResult>? pipeline) -> bool
 override Polly.ResiliencePropertyKey<TValue>.ToString() -> string!
 override Polly.Telemetry.ResilienceEvent.ToString() -> string!
-Polly.CircuitBreaker.BreakDurationGeneratorArguments
-Polly.CircuitBreaker.BreakDurationGeneratorArguments.BreakDurationGeneratorArguments() -> void
-Polly.CircuitBreaker.BreakDurationGeneratorArguments.BreakDurationGeneratorArguments(double failureRate, int failureCount, Polly.ResilienceContext! context) -> void
-Polly.CircuitBreaker.BreakDurationGeneratorArguments.BreakDurationGeneratorArguments(double failureRate, int failureCount, Polly.ResilienceContext! context, int halfOpenAttempts) -> void
-Polly.CircuitBreaker.BreakDurationGeneratorArguments.Context.get -> Polly.ResilienceContext!
-Polly.CircuitBreaker.BreakDurationGeneratorArguments.FailureCount.get -> int
-Polly.CircuitBreaker.BreakDurationGeneratorArguments.FailureRate.get -> double
-Polly.CircuitBreaker.BreakDurationGeneratorArguments.HalfOpenAttempts.get -> int
+Polly.CircuitBreaker.BreakDurationGeneratorArguments<TResult>
+Polly.CircuitBreaker.BreakDurationGeneratorArguments<TResult>.BreakDurationGeneratorArguments() -> void
+Polly.CircuitBreaker.BreakDurationGeneratorArguments<TResult>.BreakDurationGeneratorArguments(double failureRate, int failureCount, Polly.ResilienceContext! context, Polly.Outcome<TResult> outcome) -> void
+Polly.CircuitBreaker.BreakDurationGeneratorArguments<TResult>.BreakDurationGeneratorArguments(double failureRate, int failureCount, Polly.ResilienceContext! context, int halfOpenAttempts, Polly.Outcome<TResult> outcome) -> void
+Polly.CircuitBreaker.BreakDurationGeneratorArguments<TResult>.Context.get -> Polly.ResilienceContext!
+Polly.CircuitBreaker.BreakDurationGeneratorArguments<TResult>.FailureCount.get -> int
+Polly.CircuitBreaker.BreakDurationGeneratorArguments<TResult>.FailureRate.get -> double
+Polly.CircuitBreaker.BreakDurationGeneratorArguments<TResult>.HalfOpenAttempts.get -> int
+Polly.CircuitBreaker.BreakDurationGeneratorArguments<TResult>.Outcome.get -> Polly.Outcome<TResult>
 Polly.CircuitBreaker.BrokenCircuitException
 Polly.CircuitBreaker.BrokenCircuitException.BrokenCircuitException() -> void
 Polly.CircuitBreaker.BrokenCircuitException.BrokenCircuitException(string! message) -> void
@@ -41,7 +42,7 @@ Polly.CircuitBreaker.CircuitBreakerStrategyOptions.CircuitBreakerStrategyOptions
 Polly.CircuitBreaker.CircuitBreakerStrategyOptions<TResult>
 Polly.CircuitBreaker.CircuitBreakerStrategyOptions<TResult>.BreakDuration.get -> System.TimeSpan
 Polly.CircuitBreaker.CircuitBreakerStrategyOptions<TResult>.BreakDuration.set -> void
-Polly.CircuitBreaker.CircuitBreakerStrategyOptions<TResult>.BreakDurationGenerator.get -> System.Func<Polly.CircuitBreaker.BreakDurationGeneratorArguments, System.Threading.Tasks.ValueTask<System.TimeSpan>>?
+Polly.CircuitBreaker.CircuitBreakerStrategyOptions<TResult>.BreakDurationGenerator.get -> System.Func<Polly.CircuitBreaker.BreakDurationGeneratorArguments<TResult>, System.Threading.Tasks.ValueTask<System.TimeSpan>>?
 Polly.CircuitBreaker.CircuitBreakerStrategyOptions<TResult>.BreakDurationGenerator.set -> void
 Polly.CircuitBreaker.CircuitBreakerStrategyOptions<TResult>.CircuitBreakerStrategyOptions() -> void
 Polly.CircuitBreaker.CircuitBreakerStrategyOptions<TResult>.FailureRatio.get -> double

test/Polly.Core.Tests/CircuitBreaker/BreakDurationGeneratorArgumentsTests.cs

@@ -11,12 +11,14 @@ public void Constructor_Old_Ok()
         double expectedFailureRate = 0.5;
         int failureCount = 10;
         var context = new ResilienceContext();
+        var outcome = Outcome.FromResult(42);
 
-        var args = new BreakDurationGeneratorArguments(expectedFailureRate, failureCount, context);
+        var args = new BreakDurationGeneratorArguments<int>(expectedFailureRate, failureCount, context, outcome);
 
         args.FailureRate.Should().Be(expectedFailureRate);
         args.FailureCount.Should().Be(failureCount);
         args.Context.Should().Be(context);
+        args.Outcome.Should().Be(outcome);
     }
 
     [Fact]
@@ -25,12 +27,14 @@ public void Constructor_Ok()
         double expectedFailureRate = 0.5;
         int failureCount = 10;
         var context = new ResilienceContext();
+        var outcome = Outcome.FromResult(42);
 
-        var args = new BreakDurationGeneratorArguments(expectedFailureRate, failureCount, context, 99);
+        var args = new BreakDurationGeneratorArguments<int>(expectedFailureRate, failureCount, context, 99, outcome);
 
         args.FailureRate.Should().Be(expectedFailureRate);
         args.FailureCount.Should().Be(failureCount);
         args.Context.Should().Be(context);
         args.HalfOpenAttempts.Should().Be(99);
+        args.Outcome.Should().Be(outcome);
     }
 }