<PackageReference Include="Polly" Version="4.2.1" />

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API Differences between 4.2.1 and 2.2.4

135 Additions 29 Removals

Polly

• public static class AdvancedCircuitBreakerSyntax
  • public static CircuitBreakerPolicy AdvancedCircuitBreaker(this PolicyBuilder policyBuilder, double failureThreshold, TimeSpan samplingDuration, int minimumThroughput, TimeSpan durationOfBreak)
  • public static CircuitBreakerPolicy AdvancedCircuitBreaker(this PolicyBuilder policyBuilder, double failureThreshold, TimeSpan samplingDuration, int minimumThroughput, TimeSpan durationOfBreak, Action<Exception, TimeSpan> onBreak, Action onReset)
  • public static CircuitBreakerPolicy AdvancedCircuitBreaker(this PolicyBuilder policyBuilder, double failureThreshold, TimeSpan samplingDuration, int minimumThroughput, TimeSpan durationOfBreak, Action<Exception, TimeSpan, Context> onBreak, Action<Context> onReset)
  • public static CircuitBreakerPolicy AdvancedCircuitBreaker(this PolicyBuilder policyBuilder, double failureThreshold, TimeSpan samplingDuration, int minimumThroughput, TimeSpan durationOfBreak, Action<Exception, TimeSpan> onBreak, Action onReset, Action onHalfOpen)
  • public static CircuitBreakerPolicy AdvancedCircuitBreaker(this PolicyBuilder policyBuilder, double failureThreshold, TimeSpan samplingDuration, int minimumThroughput, TimeSpan durationOfBreak, Action<Exception, TimeSpan, Context> onBreak, Action<Context> onReset, Action onHalfOpen)
• public static class AdvancedCircuitBreakerSyntaxAsync
  • public static CircuitBreakerPolicy AdvancedCircuitBreakerAsync(this PolicyBuilder policyBuilder, double failureThreshold, TimeSpan samplingDuration, int minimumThroughput, TimeSpan durationOfBreak)
  • public static CircuitBreakerPolicy AdvancedCircuitBreakerAsync(this PolicyBuilder policyBuilder, double failureThreshold, TimeSpan samplingDuration, int minimumThroughput, TimeSpan durationOfBreak, Action<Exception, TimeSpan> onBreak, Action onReset)
  • public static CircuitBreakerPolicy AdvancedCircuitBreakerAsync(this PolicyBuilder policyBuilder, double failureThreshold, TimeSpan samplingDuration, int minimumThroughput, TimeSpan durationOfBreak, Action<Exception, TimeSpan, Context> onBreak, Action<Context> onReset)
  • public static CircuitBreakerPolicy AdvancedCircuitBreakerAsync(this PolicyBuilder policyBuilder, double failureThreshold, TimeSpan samplingDuration, int minimumThroughput, TimeSpan durationOfBreak, Action<Exception, TimeSpan> onBreak, Action onReset, Action onHalfOpen)
  • public static CircuitBreakerPolicy AdvancedCircuitBreakerAsync(this PolicyBuilder policyBuilder, double failureThreshold, TimeSpan samplingDuration, int minimumThroughput, TimeSpan durationOfBreak, Action<Exception, TimeSpan, Context> onBreak, Action<Context> onReset, Action onHalfOpen)
• public static class CircuitBreakerSyntax
  • public static Policy CircuitBreaker(this PolicyBuilder policyBuilder, int exceptionsAllowedBeforeBreaking, TimeSpan durationOfBreak)
  • public static CircuitBreakerPolicy CircuitBreaker(this PolicyBuilder policyBuilder, int exceptionsAllowedBeforeBreaking, TimeSpan durationOfBreak)
  • public static CircuitBreakerPolicy CircuitBreaker(this PolicyBuilder policyBuilder, int exceptionsAllowedBeforeBreaking, TimeSpan durationOfBreak, Action<Exception, TimeSpan> onBreak, Action onReset)
  • public static CircuitBreakerPolicy CircuitBreaker(this PolicyBuilder policyBuilder, int exceptionsAllowedBeforeBreaking, TimeSpan durationOfBreak, Action<Exception, TimeSpan, Context> onBreak, Action<Context> onReset)
  • public static CircuitBreakerPolicy CircuitBreaker(this PolicyBuilder policyBuilder, int exceptionsAllowedBeforeBreaking, TimeSpan durationOfBreak, Action<Exception, TimeSpan> onBreak, Action onReset, Action onHalfOpen)
  • public static CircuitBreakerPolicy CircuitBreaker(this PolicyBuilder policyBuilder, int exceptionsAllowedBeforeBreaking, TimeSpan durationOfBreak, Action<Exception, TimeSpan, Context> onBreak, Action<Context> onReset, Action onHalfOpen)
• public static class CircuitBreakerSyntaxAsync
  • public static Policy CircuitBreakerAsync(this PolicyBuilder policyBuilder, int exceptionsAllowedBeforeBreaking, TimeSpan durationOfBreak)
  • public static CircuitBreakerPolicy CircuitBreakerAsync(this PolicyBuilder policyBuilder, int exceptionsAllowedBeforeBreaking, TimeSpan durationOfBreak)
  • public static CircuitBreakerPolicy CircuitBreakerAsync(this PolicyBuilder policyBuilder, int exceptionsAllowedBeforeBreaking, TimeSpan durationOfBreak, Action<Exception, TimeSpan> onBreak, Action onReset)
  • public static CircuitBreakerPolicy CircuitBreakerAsync(this PolicyBuilder policyBuilder, int exceptionsAllowedBeforeBreaking, TimeSpan durationOfBreak, Action<Exception, TimeSpan, Context> onBreak, Action<Context> onReset)
  • public static CircuitBreakerPolicy CircuitBreakerAsync(this PolicyBuilder policyBuilder, int exceptionsAllowedBeforeBreaking, TimeSpan durationOfBreak, Action<Exception, TimeSpan> onBreak, Action onReset, Action onHalfOpen)
  • public static CircuitBreakerPolicy CircuitBreakerAsync(this PolicyBuilder policyBuilder, int exceptionsAllowedBeforeBreaking, TimeSpan durationOfBreak, Action<Exception, TimeSpan, Context> onBreak, Action<Context> onReset, Action onHalfOpen)
• public class ContextualPolicy : Policy
  • public void Execute(Action action)
  • public TResult Execute<TResult>(Func<TResult> action)
  • public PolicyResult ExecuteAndCapture(Action action, IDictionary<string, object> contextData)
  • public PolicyResult<TResult> ExecuteAndCapture<TResult>(Func<TResult> action, IDictionary<string, object> contextData)
  • public Task<PolicyResult> ExecuteAndCaptureAsync(Func<Task> action, IDictionary<string, object> contextData)
  • public Task<PolicyResult> ExecuteAndCaptureAsync(Func<Task> action, IDictionary<string, object> contextData, bool continueOnCapturedContext)
  • public Task<PolicyResult> ExecuteAndCaptureAsync(Func<CancellationToken, Task> action, IDictionary<string, object> contextData, CancellationToken cancellationToken)
  • public Task<PolicyResult> ExecuteAndCaptureAsync(Func<CancellationToken, Task> action, IDictionary<string, object> contextData, CancellationToken cancellationToken, bool continueOnCapturedContext)
  • public Task<PolicyResult<TResult>> ExecuteAndCaptureAsync<TResult>(Func<Task<TResult>> action, IDictionary<string, object> contextData)
  • protected Task<PolicyResult<TResult>> ExecuteAndCaptureAsync<TResult>(Func<Task<TResult>> action, IDictionary<string, object> contextData, bool continueOnCapturedContext)
  • public Task<PolicyResult<TResult>> ExecuteAndCaptureAsync<TResult>(Func<Task<TResult>> action, IDictionary<string, object> contextData, CancellationToken cancellationToken)
  • public Task<PolicyResult<TResult>> ExecuteAndCaptureAsync<TResult>(Func<CancellationToken, Task<TResult>> action, IDictionary<string, object> contextData, CancellationToken cancellationToken, bool continueOnCapturedContext)
  • public Task ExecuteAsync(Func<Task> action, IDictionary<string, object> contextData)
  • public Task ExecuteAsync(Func<Task> action, IDictionary<string, object> contextData, bool continueOnCapturedContext)
  • public Task ExecuteAsync(Func<CancellationToken, Task> action, IDictionary<string, object> contextData, CancellationToken cancellationToken)
  • public Task ExecuteAsync(Func<CancellationToken, Task> action, IDictionary<string, object> contextData, CancellationToken cancellationToken, bool continueOnCapturedContext)
  • public Task<TResult> ExecuteAsync<TResult>(Func<Task<TResult>> action, IDictionary<string, object> contextData)
  • public Task<TResult> ExecuteAsync<TResult>(Func<Task<TResult>> action, IDictionary<string, object> contextData, bool continueOnCapturedContext)
  • public Task<TResult> ExecuteAsync<TResult>(Func<CancellationToken, Task<TResult>> action, IDictionary<string, object> contextData, CancellationToken cancellationToken)
  • public Task<TResult> ExecuteAsync<TResult>(Func<CancellationToken, Task<TResult>> action, IDictionary<string, object> contextData, CancellationToken cancellationToken, bool continueOnCapturedContext)
• public class Policy
  • protected void Execute(Action action, Context context)
  • protected TResult Execute<TResult>(Func<TResult> action, Context context)
  • protected PolicyResult ExecuteAndCapture(Action action, Context context)
  • protected PolicyResult<TResult> ExecuteAndCapture<TResult>(Func<TResult> action, Context context)
  • protected Task<PolicyResult> ExecuteAndCaptureAsync(Func<Task> action, Context context)
  • public Task<PolicyResult> ExecuteAndCaptureAsync(Func<Task> action, bool continueOnCapturedContext)
  • protected Task<PolicyResult> ExecuteAndCaptureAsync(Func<Task> action, Context context, bool continueOnCapturedContext)
  • public Task<PolicyResult> ExecuteAndCaptureAsync(Func<CancellationToken, Task> action, CancellationToken cancellationToken)
  • protected Task<PolicyResult> ExecuteAndCaptureAsync(Func<CancellationToken, Task> action, Context context, CancellationToken cancellationToken)
  • public Task<PolicyResult> ExecuteAndCaptureAsync(Func<CancellationToken, Task> action, CancellationToken cancellationToken, bool continueOnCapturedContext)
  • protected Task<PolicyResult> ExecuteAndCaptureAsync(Func<CancellationToken, Task> action, Context context, CancellationToken cancellationToken, bool continueOnCapturedContext)
  • protected Task<PolicyResult<TResult>> ExecuteAndCaptureAsync<TResult>(Func<Task<TResult>> action, Context context)
  • public Task<PolicyResult<TResult>> ExecuteAndCaptureAsync<TResult>(Func<Task<TResult>> action, bool continueOnCapturedContext)
  • protected Task<PolicyResult<TResult>> ExecuteAndCaptureAsync<TResult>(Func<Task<TResult>> action, Context context, bool continueOnCapturedContext)
  • public Task<PolicyResult<TResult>> ExecuteAndCaptureAsync<TResult>(Func<Task<TResult>> action, CancellationToken cancellationToken)
  • protected Task<PolicyResult<TResult>> ExecuteAndCaptureAsync<TResult>(Func<Task<TResult>> action, Context context, CancellationToken cancellationToken)
  • public Task<PolicyResult<TResult>> ExecuteAndCaptureAsync<TResult>(Func<CancellationToken, Task<TResult>> action, CancellationToken cancellationToken, bool continueOnCapturedContext)
  • protected Task<PolicyResult<TResult>> ExecuteAndCaptureAsync<TResult>(Func<CancellationToken, Task<TResult>> action, Context context, CancellationToken cancellationToken, bool continueOnCapturedContext)
  • protected Task ExecuteAsync(Func<Task> action, Context context)
  • public Task ExecuteAsync(Func<Task> action, bool continueOnCapturedContext)
  • protected Task ExecuteAsync(Func<Task> action, Context context, bool continueOnCapturedContext)
  • public Task ExecuteAsync(Func<CancellationToken, Task> action, CancellationToken cancellationToken)
  • protected Task ExecuteAsync(Func<CancellationToken, Task> action, Context context, CancellationToken cancellationToken)
  • public Task ExecuteAsync(Func<CancellationToken, Task> action, CancellationToken cancellationToken, bool continueOnCapturedContext)
  • protected Task ExecuteAsync(Func<CancellationToken, Task> action, Context context, CancellationToken cancellationToken, bool continueOnCapturedContext)
  • protected Task<TResult> ExecuteAsync<TResult>(Func<Task<TResult>> action, Context context)
  • public Task<TResult> ExecuteAsync<TResult>(Func<CancellationToken, Task<TResult>> action, CancellationToken cancellationToken)
  • protected Task<TResult> ExecuteAsync<TResult>(Func<CancellationToken, Task<TResult>> action, Context context, CancellationToken cancellationToken)
  • public Task<TResult> ExecuteAsync<TResult>(Func<Task<TResult>> action, bool continueOnCapturedContext)
  • protected Task<TResult> ExecuteAsync<TResult>(Func<Task<TResult>> action, Context context, bool continueOnCapturedContext)
  • public Task<TResult> ExecuteAsync<TResult>(Func<CancellationToken, Task<TResult>> action, CancellationToken cancellationToken, bool continueOnCapturedContext)
  • protected Task<TResult> ExecuteAsync<TResult>(Func<CancellationToken, Task<TResult>> action, Context context, CancellationToken cancellationToken, bool continueOnCapturedContext)
• public static class RetrySyntax
  • public static Policy Retry(this PolicyBuilder policyBuilder)
  • public static Policy Retry(this PolicyBuilder policyBuilder, int retryCount)
  • public static Policy Retry(this PolicyBuilder policyBuilder, Action<Exception, int> onRetry)
  • public static Policy Retry(this PolicyBuilder policyBuilder, int retryCount, Action<Exception, int> onRetry)
  • public static ContextualPolicy Retry(this PolicyBuilder policyBuilder, Action<Exception, int, Context> onRetry)
  • public static ContextualPolicy Retry(this PolicyBuilder policyBuilder, int retryCount, Action<Exception, int, Context> onRetry)
  • public static Policy RetryAsync(this PolicyBuilder policyBuilder)
  • public static Policy RetryAsync(this PolicyBuilder policyBuilder, int retryCount)
  • public static Policy RetryAsync(this PolicyBuilder policyBuilder, Action<Exception, int> onRetry)
  • public static Policy RetryAsync(this PolicyBuilder policyBuilder, int retryCount, Action<Exception, int> onRetry)
  • public static Policy RetryForever(this PolicyBuilder policyBuilder)
  • public static Policy RetryForever(this PolicyBuilder policyBuilder, Action<Exception> onRetry)
  • public static ContextualPolicy RetryForever(this PolicyBuilder policyBuilder, Action<Exception, Context> onRetry)
  • public static Policy RetryForeverAsync(this PolicyBuilder policyBuilder)
  • public static Policy RetryForeverAsync(this PolicyBuilder policyBuilder, Action<Exception> onRetry)
  • public static Policy WaitAndRetry(this PolicyBuilder policyBuilder, int retryCount, Func<int, TimeSpan> sleepDurationProvider)
  • public static Policy WaitAndRetry(this PolicyBuilder policyBuilder, int retryCount, Func<int, TimeSpan> sleepDurationProvider, Action<Exception, TimeSpan> onRetry)
  • public static ContextualPolicy WaitAndRetry(this PolicyBuilder policyBuilder, int retryCount, Func<int, TimeSpan> sleepDurationProvider, Action<Exception, TimeSpan, Context> onRetry)
  • public static Policy WaitAndRetry(this PolicyBuilder policyBuilder, IEnumerable<TimeSpan> sleepDurations)
  • public static Policy WaitAndRetry(this PolicyBuilder policyBuilder, IEnumerable<TimeSpan> sleepDurations, Action<Exception, TimeSpan> onRetry)
  • public static ContextualPolicy WaitAndRetry(this PolicyBuilder policyBuilder, IEnumerable<TimeSpan> sleepDurations, Action<Exception, TimeSpan, Context> onRetry)
  • public static Policy WaitAndRetryAsync(this PolicyBuilder policyBuilder, IEnumerable<TimeSpan> sleepDurations)
  • public static Policy WaitAndRetryAsync(this PolicyBuilder policyBuilder, int retryCount, Func<int, TimeSpan> sleepDurationProvider)
  • public static Policy WaitAndRetryAsync(this PolicyBuilder policyBuilder, int retryCount, Func<int, TimeSpan> sleepDurationProvider, Action<Exception, TimeSpan> onRetry)
  • public static Policy WaitAndRetryAsync(this PolicyBuilder policyBuilder, IEnumerable<TimeSpan> sleepDurations, Action<Exception, TimeSpan> onRetry)
  • public static RetryPolicy Retry(this PolicyBuilder policyBuilder)
  • public static RetryPolicy Retry(this PolicyBuilder policyBuilder, int retryCount)
  • public static RetryPolicy Retry(this PolicyBuilder policyBuilder, Action<Exception, int> onRetry)
  • public static RetryPolicy Retry(this PolicyBuilder policyBuilder, int retryCount, Action<Exception, int> onRetry)
  • public static RetryPolicy Retry(this PolicyBuilder policyBuilder, Action<Exception, int, Context> onRetry)
  • public static RetryPolicy Retry(this PolicyBuilder policyBuilder, int retryCount, Action<Exception, int, Context> onRetry)
  • public static RetryPolicy RetryAsync(this PolicyBuilder policyBuilder)
  • public static RetryPolicy RetryAsync(this PolicyBuilder policyBuilder, int retryCount)
  • public static RetryPolicy RetryAsync(this PolicyBuilder policyBuilder, Action<Exception, int> onRetry)
  • public static RetryPolicy RetryAsync(this PolicyBuilder policyBuilder, Func<Exception, int, Task> onRetryAsync)
  • public static RetryPolicy RetryAsync(this PolicyBuilder policyBuilder, int retryCount, Action<Exception, int> onRetry)
  • public static RetryPolicy RetryAsync(this PolicyBuilder policyBuilder, int retryCount, Func<Exception, int, Task> onRetryAsync)
  • public static RetryPolicy RetryAsync(this PolicyBuilder policyBuilder, Action<Exception, int, Context> onRetry)
  • public static RetryPolicy RetryAsync(this PolicyBuilder policyBuilder, Func<Exception, int, Context, Task> onRetryAsync)
  • public static RetryPolicy RetryAsync(this PolicyBuilder policyBuilder, int retryCount, Action<Exception, int, Context> onRetry)
  • public static RetryPolicy RetryAsync(this PolicyBuilder policyBuilder, int retryCount, Func<Exception, int, Context, Task> onRetryAsync)
  • public static RetryPolicy RetryForever(this PolicyBuilder policyBuilder)
  • public static RetryPolicy RetryForever(this PolicyBuilder policyBuilder, Action<Exception> onRetry)
  • public static RetryPolicy RetryForever(this PolicyBuilder policyBuilder, Action<Exception, Context> onRetry)
  • public static RetryPolicy RetryForeverAsync(this PolicyBuilder policyBuilder)
  • public static RetryPolicy RetryForeverAsync(this PolicyBuilder policyBuilder, Action<Exception> onRetry)
  • public static RetryPolicy RetryForeverAsync(this PolicyBuilder policyBuilder, Func<Exception, Task> onRetryAsync)
  • public static RetryPolicy RetryForeverAsync(this PolicyBuilder policyBuilder, Action<Exception, Context> onRetry)
  • public static RetryPolicy RetryForeverAsync(this PolicyBuilder policyBuilder, Func<Exception, Context, Task> onRetryAsync)
  • public static RetryPolicy WaitAndRetry(this PolicyBuilder policyBuilder, int retryCount, Func<int, TimeSpan> sleepDurationProvider)
  • public static RetryPolicy WaitAndRetry(this PolicyBuilder policyBuilder, int retryCount, Func<int, TimeSpan> sleepDurationProvider, Action<Exception, TimeSpan> onRetry)
  • public static RetryPolicy WaitAndRetry(this PolicyBuilder policyBuilder, int retryCount, Func<int, TimeSpan> sleepDurationProvider, Action<Exception, TimeSpan, Context> onRetry)
  • public static RetryPolicy WaitAndRetry(this PolicyBuilder policyBuilder, IEnumerable<TimeSpan> sleepDurations)
  • public static RetryPolicy WaitAndRetry(this PolicyBuilder policyBuilder, IEnumerable<TimeSpan> sleepDurations, Action<Exception, TimeSpan> onRetry)
  • public static RetryPolicy WaitAndRetry(this PolicyBuilder policyBuilder, IEnumerable<TimeSpan> sleepDurations, Action<Exception, TimeSpan, Context> onRetry)
  • public static RetryPolicy WaitAndRetryAsync(this PolicyBuilder policyBuilder, int retryCount, Func<int, TimeSpan> sleepDurationProvider)
  • public static RetryPolicy WaitAndRetryAsync(this PolicyBuilder policyBuilder, int retryCount, Func<int, TimeSpan> sleepDurationProvider, Action<Exception, TimeSpan> onRetry)
  • public static RetryPolicy WaitAndRetryAsync(this PolicyBuilder policyBuilder, int retryCount, Func<int, TimeSpan> sleepDurationProvider, Func<Exception, TimeSpan, Task> onRetryAsync)
  • public static RetryPolicy WaitAndRetryAsync(this PolicyBuilder policyBuilder, int retryCount, Func<int, TimeSpan> sleepDurationProvider, Action<Exception, TimeSpan, Context> onRetry)
  • public static RetryPolicy WaitAndRetryAsync(this PolicyBuilder policyBuilder, int retryCount, Func<int, TimeSpan> sleepDurationProvider, Func<Exception, TimeSpan, Context, Task> onRetryAsync)
  • public static RetryPolicy WaitAndRetryAsync(this PolicyBuilder policyBuilder, IEnumerable<TimeSpan> sleepDurations)
  • public static RetryPolicy WaitAndRetryAsync(this PolicyBuilder policyBuilder, IEnumerable<TimeSpan> sleepDurations, Action<Exception, TimeSpan> onRetry)
  • public static RetryPolicy WaitAndRetryAsync(this PolicyBuilder policyBuilder, IEnumerable<TimeSpan> sleepDurations, Func<Exception, TimeSpan, Task> onRetryAsync)
  • public static RetryPolicy WaitAndRetryAsync(this PolicyBuilder policyBuilder, IEnumerable<TimeSpan> sleepDurations, Action<Exception, TimeSpan, Context> onRetry)
  • public static RetryPolicy WaitAndRetryAsync(this PolicyBuilder policyBuilder, IEnumerable<TimeSpan> sleepDurations, Func<Exception, TimeSpan, Context, Task> onRetryAsync)
  • public static RetryPolicy WaitAndRetryForever(this PolicyBuilder policyBuilder, Func<int, TimeSpan> sleepDurationProvider)
  • public static RetryPolicy WaitAndRetryForever(this PolicyBuilder policyBuilder, Func<int, TimeSpan> sleepDurationProvider, Action<Exception, TimeSpan> onRetry)
  • public static RetryPolicy WaitAndRetryForever(this PolicyBuilder policyBuilder, Func<int, TimeSpan> sleepDurationProvider, Action<Exception, TimeSpan, Context> onRetry)
  • public static RetryPolicy WaitAndRetryForeverAsync(this PolicyBuilder policyBuilder, Func<int, TimeSpan> sleepDurationProvider)
  • public static RetryPolicy WaitAndRetryForeverAsync(this PolicyBuilder policyBuilder, Func<int, TimeSpan> sleepDurationProvider, Action<Exception, TimeSpan> onRetry)
  • public static RetryPolicy WaitAndRetryForeverAsync(this PolicyBuilder policyBuilder, Func<int, TimeSpan> sleepDurationProvider, Func<Exception, TimeSpan, Task> onRetryAsync)
  • public static RetryPolicy WaitAndRetryForeverAsync(this PolicyBuilder policyBuilder, Func<int, TimeSpan> sleepDurationProvider, Action<Exception, TimeSpan, Context> onRetry)
  • public static RetryPolicy WaitAndRetryForeverAsync(this PolicyBuilder policyBuilder, Func<int, TimeSpan> sleepDurationProvider, Func<Exception, TimeSpan, Context, Task> onRetryAsync)

Polly.CircuitBreaker

• public class CircuitBreakerPolicy : ContextualPolicy
  • public CircuitState CircuitState { get; }
  • public Exception LastException { get; }
  • public void Isolate()
  • public void Reset()
• public enum CircuitState
  • Closed = 0
  • HalfOpen = 2
  • Isolated = 3
  • Open = 1
• public class IsolatedCircuitException : BrokenCircuitException
  • public IsolatedCircuitException(string message)
  • protected IsolatedCircuitException(SerializationInfo info, StreamingContext context)

Polly.Retry

• public class RetryPolicy : ContextualPolicy

Polly.Utilities

• public static class SystemClock
  • public static Func<TimeSpan, CancellationToken, Task> SleepAsync