Polly 8 sometimes throws InvalidCastException of System.TimeSpan to System.String on Timeout TimeSpan and Retry TimeSpan

[jerryguo95]

I'm seeing that an InvalidCastException exception is thrown around 0.03% of time, when creating a new default ResiliencePipeline via ResiliencePipelineBuilder().

                var pipeline = new ResiliencePipelineBuilder()
                .AddRetry(new RetryStrategyOptions()
                {
                    MaxRetryAttempts = 3,
                    OnRetry = args =>
                    {
                        Console.WriteLine($"Result: {args.Outcome}. Retrying attempt number: {args.AttemptNumber}.");
                        return default;
                    }
                })
                .AddTimeout(TimeSpan.FromSeconds(30));
                .Build();

The exception that gets thrown is sometimes due to the AddRetry, other times, it's due to the AddTimeout

AddTimeout exception stack trace:

message=Hit an exception while handling data : System.InvalidCastException | Unable to cast object of type 'System.TimeSpan' to type 'System.String'., exception=System.InvalidCastException: Unable to cast object of type 'System.TimeSpan' to type 'System.String'.
   at System.ComponentModel.DataAnnotations.RangeAttribute.SetupConversion()
   at System.ComponentModel.DataAnnotations.RangeAttribute.IsValid(Object value)
   at System.ComponentModel.DataAnnotations.ValidationAttribute.IsValid(Object value, ValidationContext validationContext)
   at System.ComponentModel.DataAnnotations.ValidationAttribute.GetValidationResult(Object value, ValidationContext validationContext)
   at System.ComponentModel.DataAnnotations.Validator.TryValidate(Object value, ValidationContext validationContext, ValidationAttribute attribute, ValidationError& validationError)
   at System.ComponentModel.DataAnnotations.Validator.GetValidationErrors(Object value, ValidationContext validationContext, IEnumerable`1 attributes, Boolean breakOnFirstError)
   at System.ComponentModel.DataAnnotations.Validator.GetObjectPropertyValidationErrors(Object instance, ValidationContext validationContext, Boolean validateAllProperties, Boolean breakOnFirstError)
   at System.ComponentModel.DataAnnotations.Validator.GetObjectValidationErrors(Object instance, ValidationContext validationContext, Boolean validateAllProperties, Boolean breakOnFirstError)
   at System.ComponentModel.DataAnnotations.Validator.TryValidateObject(Object instance, ValidationContext validationContext, ICollection`1 validationResults, Boolean validateAllProperties)
   at Polly.Utils.ValidationHelper.ValidateObject(ResilienceValidationContext context)
   at Polly.ResiliencePipelineBuilderBase.AddPipelineComponent(Func`2 factory, ResilienceStrategyOptions options)
   at Polly.ResiliencePipelineBuilderExtensions.AddStrategy[TBuilder](TBuilder builder, Func`2 factory, ResilienceStrategyOptions options)
   at Polly.TimeoutResiliencePipelineBuilderExtensions.AddTimeout[TBuilder](TBuilder builder, TimeoutStrategyOptions options)
   at Polly.TimeoutResiliencePipelineBuilderExtensions.AddTimeout[TBuilder](TBuilder builder, TimeSpan timeout)

AddRetry throwing the exception call stack:

System.InvalidCastException | Unable to cast object of type 'System.TimeSpan' to type 'System.String'., exception=System.InvalidCastException: Unable to cast object of type 'System.TimeSpan' to type 'System.String'.
   at System.ComponentModel.DataAnnotations.RangeAttribute.SetupConversion()
   at System.ComponentModel.DataAnnotations.RangeAttribute.IsValid(Object value)
   at System.ComponentModel.DataAnnotations.ValidationAttribute.IsValid(Object value, ValidationContext validationContext)
   at System.ComponentModel.DataAnnotations.ValidationAttribute.GetValidationResult(Object value, ValidationContext validationContext)
   at System.ComponentModel.DataAnnotations.Validator.TryValidate(Object value, ValidationContext validationContext, ValidationAttribute attribute, ValidationError& validationError)
   at System.ComponentModel.DataAnnotations.Validator.GetValidationErrors(Object value, ValidationContext validationContext, IEnumerable`1 attributes, Boolean breakOnFirstError)
   at System.ComponentModel.DataAnnotations.Validator.GetObjectPropertyValidationErrors(Object instance, ValidationContext validationContext, Boolean validateAllProperties, Boolean breakOnFirstError)
   at System.ComponentModel.DataAnnotations.Validator.GetObjectValidationErrors(Object instance, ValidationContext validationContext, Boolean validateAllProperties, Boolean breakOnFirstError)
   at System.ComponentModel.DataAnnotations.Validator.TryValidateObject(Object instance, ValidationContext validationContext, ICollection`1 validationResults, Boolean validateAllProperties)
   at Polly.Utils.ValidationHelper.ValidateObject(ResilienceValidationContext context)
   at Polly.ResiliencePipelineBuilderBase.AddPipelineComponent(Func`2 factory, ResilienceStrategyOptions options)
   at Polly.ResiliencePipelineBuilderExtensions.AddStrategy(ResiliencePipelineBuilder builder, Func`2 factory, ResilienceStrategyOptions options)
   at Polly.RetryResiliencePipelineBuilderExtensions.AddRetry(ResiliencePipelineBuilder builder, RetryStrategyOptions options)

This runs on a linux machine and using Polly version 8.3.1 and .net6.0.

[martincostello]

This sounds a lot like this issue that was fixed in .NET 8.0.2: dotnet/runtime#97037

That in turn required the library hitting the code to be re-compiled with the fix.