static Task <HttpResponseMessage> HandleTransientErrors(Task <HttpResponseMessage> request, object state)
{
var executor = (RetryStrategyExecutor)state;
if (!request.IsFaulted)
{
var response = request.Result;
if (executor.CanContinue && Misc.IsTransientError(response))
{
Log.To.Sync.V(Tag, "Retrying after transient error...");
return(executor.Retry());
}
if (!response.IsSuccessStatusCode)
{
Log.To.Sync.V(Tag, "Non transient error received ({0}), throwing HttpResponseException",
response.StatusCode);
var exception = new HttpResponseException(response.StatusCode);
if (response.StatusCode == HttpStatusCode.Unauthorized || response.StatusCode ==
HttpStatusCode.ProxyAuthenticationRequired)
{
var responseChallenge = response.Headers.WwwAuthenticate;
foreach (var header in responseChallenge)
{
var challenge = AuthUtils.ParseAuthHeader(header);
if (challenge != null)
{
exception.Data["AuthChallenge"] = challenge;
}
}
}
throw exception;
}
// If it's not faulted, there's nothing here to do.
return(request);
}
string statusCode;
if (!Misc.IsTransientNetworkError(request.Exception, out statusCode) || !executor.CanContinue)
{
if (!executor.CanContinue)
{
Log.To.Sync.V(Tag, "Out of retries for error, throwing", request.Exception);
}
else
{
Log.To.Sync.V(Tag, "Non transient error received (status), throwing", request.Exception);
}
// If it's not transient, pass the exception along
// for any other handlers to respond to.
throw request.Exception;
}
// Retry again.
Log.To.Sync.V(Tag, "Retrying after transient error...");
return(executor.Retry());
}
static Task <HttpResponseMessage> HandleTransientErrors(Task <HttpResponseMessage> request, object state)
{
var executor = (RetryStrategyExecutor)state;
if (executor.Token.IsCancellationRequested)
{
executor.Token = new CancellationToken();
}
if (!request.IsFaulted)
{
if (request.IsCanceled)
{
if (executor.CanContinue)
{
Log.To.Sync.V(Tag, "Retrying after cancellation (i.e. HTTP timeout)");
return(executor.Retry());
}
else
{
throw new TaskCanceledException("HTTP timeout");
}
}
var response = request.Result;
if (executor.CanContinue && ExceptionResolver.IsTransientError(response))
{
Log.To.Sync.V(Tag, "Retrying after transient error...");
return(executor.Retry());
}
if (!response.IsSuccessStatusCode)
{
Log.To.Sync.V(Tag, "Non transient error received ({0}), throwing HttpResponseException",
response.StatusCode);
var exception = new HttpResponseException(response.StatusCode);
if (response.StatusCode == HttpStatusCode.Unauthorized || response.StatusCode ==
HttpStatusCode.ProxyAuthenticationRequired)
{
var responseChallenge = response.Headers.WwwAuthenticate;
foreach (var header in responseChallenge)
{
var challenge = AuthUtils.ParseAuthHeader(header);
if (challenge != null)
{
exception.Data["AuthChallenge"] = challenge;
}
}
}
throw exception;
}
// If it's not faulted, there's nothing here to do.
return(request);
}
var resolution = ExceptionResolver.Solve(request.Exception, new ExceptionResolverOptions {
HasRetries = executor.CanContinue
});
if (resolution.Resolution == ErrorResolution.Stop)
{
if (resolution.ResolutionFlags.HasFlag(ErrorResolutionFlags.OutOfRetries))
{
Log.To.Sync.V(Tag, "Out of retries for error, throwing", request.Exception);
}
else
{
Log.To.Sync.V(Tag, "Non transient error received (status), throwing", request.Exception);
}
// If it's not transient, pass the exception along
// for any other handlers to respond to.
throw request.Exception;
}
// Retry again.
Log.To.Sync.V(Tag, "Retrying after transient error...");
return(executor.Retry());
}