public override async Task <TReturn> HandleExceptionAsync <TReturn>(Func <CancellationToken, Task <TReturn> > func, CancellationToken funcCancellationToken = default, Func <CancellationToken, Task> onExceptionCompensatingHandler = null, CancellationToken onExceptionCompensatingHandlerCancellationToken = default)
{
Task <TReturn> returnValue = default;
try
{
var returnValueFromFunc = await func(funcCancellationToken);
if (returnValueFromFunc is Task <TReturn> )
{
returnValue = returnValueFromFunc as Task <TReturn>;
}
else
{
returnValue = Task.FromResult(returnValueFromFunc);
}
}
catch (Exception ex)
{
returnValue = await ExceptionHandlingUtility.WrapFuncWithExceptionHandling(async() =>
{
if (CheckIfExceptionsNeedsToBePollyHandled(ex))
{
AsyncPolicyWrap policyWrap = GetPolicyWrapWithProperFallbackActionSetForFallbackPoliciesAsync(ex, onExceptionCompensatingHandler);
return(await policyWrap.ExecuteAsync(func, funcCancellationToken) as Task <TReturn>);
}
return(default(Task <TReturn>));
}, _logger);
await HandleExceptionWithThrowCondition(ex, onExceptionCompensatingHandler, onExceptionCompensatingHandlerCancellationToken);
}
return(await returnValue);
}
private static PolicyBuilder BuildPolicyBuilderFromPollyTransientFailureExceptionsXMLFile()
{
return(ExceptionHandlingUtility.WrapFuncWithExceptionHandling(() =>
{
PolicyBuilder policyBuilder = null;
XDocument xDoc = XDocument.Load(Path.Combine(typeof(BasicPollyExceptionHandler).Assembly.Location, "ExceptionHandling", "PollyBasedExceptionHandling", "PollyTransientFailureExceptions.xml"));
_pollyTransientFailureExceptions = XMLUtility.DeSerialize <PollyTransientFailureExceptions>(xDoc.ToString());
_splittedTransientFailureExceptions = _pollyTransientFailureExceptions.TransientFailureExceptions.SelectMany(x => x.CommaSeperatedTransientFailureExceptions.Split(",", StringSplitOptions.RemoveEmptyEntries)).Distinct();
if (_splittedTransientFailureExceptions.IsNotNullOrEmpty())
{
string firstTransientFailureException = _splittedTransientFailureExceptions.First();
string assemblyName = _pollyTransientFailureExceptions.TransientFailureExceptions.SingleOrDefault(x => x.CommaSeperatedTransientFailureExceptions.Contains(firstTransientFailureException)).AssemblyName;
Type firstTransientFailureExceptionType = MetaDataUtility.GetType(assemblyName, firstTransientFailureException);
Type[] transientFailureExceptionTypesArray = new Type[1];
transientFailureExceptionTypesArray[0] = firstTransientFailureExceptionType;
policyBuilder = MetaDataUtility.InvokeStaticMethod <Policy, PolicyBuilder>("Handle", transientFailureExceptionTypesArray);
IEnumerable <string> transientFailureExceptionsOtherThanTheFirst = _splittedTransientFailureExceptions.Skip(1);
if (transientFailureExceptionsOtherThanTheFirst.IsNotNullOrEmpty())
{
transientFailureExceptionsOtherThanTheFirst.ForEach(x =>
{
assemblyName = _pollyTransientFailureExceptions.TransientFailureExceptions.SingleOrDefault(y => y.CommaSeperatedTransientFailureExceptions.Contains(x)).AssemblyName;
Type transientFailureExceptionTypeForOtherThanTheFirst = MetaDataUtility.GetType(assemblyName, x);
Type[] transientFailureExceptionTypesArrayForOtherThanTheFirst = new Type[1];
transientFailureExceptionTypesArrayForOtherThanTheFirst[0] = transientFailureExceptionTypeForOtherThanTheFirst;
policyBuilder = MetaDataUtility.InvokeInstanceMethod <PolicyBuilder, PolicyBuilder>(policyBuilder, "Or", transientFailureExceptionTypesArrayForOtherThanTheFirst);
}
);
}
}
return policyBuilder;
}, _staticLoggerInstance));
}
public override TReturn HandleException <TReturn>(Func <TReturn> action, Action onExceptionCompensatingHandler = null)
{
TReturn returnValue = default(TReturn);
try
{
returnValue = action();
}
catch (Exception ex)
{
returnValue = ExceptionHandlingUtility.WrapFuncWithExceptionHandling(() =>
{
if (CheckIfExceptionsNeedsToBePollyHandled(ex))
{
PolicyWrap policyWrap = GetPolicyWrapWithProperFallbackActionSetForFallbackPolicies(ex, onExceptionCompensatingHandler);
return(policyWrap.Execute(action));
}
return(default(TReturn));
}, _logger);
HandleExceptionWithThrowCondition(ex, onExceptionCompensatingHandler);
}
return(returnValue);
}
public override TReturn HandleException <TReturn>(Func <TReturn> action, Action onExceptionCompensatingHandler = null)
{
TReturn returnValue = default(TReturn);
try
{
returnValue = action();
}
catch (Exception ex)
{
returnValue = ExceptionHandlingUtility.WrapFuncWithExceptionHandling(() =>
{
if (_splittedTransientFailureExceptions.IsNotNullOrEmpty() && _splittedTransientFailureExceptions.Contains(ex.GetType().Name) && _policies.IsNotNullOrEmpty())
{
PolicyWrap policyWrap = GetPolicyWrapWithProperFallbackActionSetForFallbackPolicies(ex, onExceptionCompensatingHandler);
return(policyWrap.Execute(action));
}
return(default(TReturn));
}, _logger);
HandleExceptionWithThrowCondition(ex, onExceptionCompensatingHandler);
}
return(returnValue);
}
public override async Task <TReturn> HandleExceptionAsync <TReturn>(Func <CancellationToken, Task <TReturn> > func, CancellationToken funcCancellationToken = default(CancellationToken), Func <CancellationToken, Task> onExceptionCompensatingHandler = null, CancellationToken onExceptionCompensatingHandlerCancellationToken = default(CancellationToken))
{
Task <TReturn> returnValue = default(Task <TReturn>);
try
{
returnValue = await func(funcCancellationToken) as Task <TReturn>;
}
catch (Exception ex)
{
returnValue = await ExceptionHandlingUtility.WrapFuncWithExceptionHandling(async() =>
{
if (_splittedTransientFailureExceptions.IsNotNullOrEmpty() && _splittedTransientFailureExceptions.Contains(ex.GetType().Name) && _policies.IsNotNullOrEmpty())
{
PolicyWrap policyWrap = GetPolicyWrapWithProperFallbackActionSetForFallbackPoliciesAsync(ex, onExceptionCompensatingHandler);
return(await policyWrap.ExecuteAsync(func, funcCancellationToken) as Task <TReturn>);
}
return(default(Task <TReturn>));
}, _logger);
await HandleExceptionWithThrowCondition(ex, onExceptionCompensatingHandler, onExceptionCompensatingHandlerCancellationToken);
}
return(await returnValue);
}