/// <summary>
/// Return true if the request should be retried. Implements additional checks
/// specific to S3 on top of the checks in DefaultRetryPolicy.
/// </summary>
/// <param name="executionContext">Request context containing the state of the request.</param>
/// <param name="exception">The exception thrown by the previous request.</param>
/// <returns>Return true if the request should be retried.</returns>
public override bool RetryForException(Runtime.IExecutionContext executionContext, Exception exception)
{
var serviceException = exception as AmazonServiceException;
if (serviceException != null)
{
if (serviceException.StatusCode == HttpStatusCode.OK)
{
var requestType = executionContext.RequestContext.OriginalRequest.GetType();
if (AmazonS3RetryPolicy.RequestsWith200Error.Contains(requestType))
{
// Retry on HTTP 200 responses which contain an error response.
// CopyObject, CopyPart and CompleteMultipartUpload operations can return this
// response.
return(true);
}
}
if (serviceException.StatusCode == HttpStatusCode.BadRequest)
{
var configuredUri = new Uri(executionContext.RequestContext.ClientConfig.DetermineServiceURL());
if (configuredUri.Host.Equals(S3Constants.S3DefaultEndpoint) &&
(serviceException.Message.Contains(AWS4Signer.AWS4AlgorithmTag) ||
serviceException.Message.Contains(AWS_KMS_Signature_Error))
)
{
// If the response message indicates AWS4 signing should have been used,
// we've attempted to access a bucket in an AWS4-only region (e.g. EU Central (Frankfurt)) with an AWS2
// signature and/or client not configured with the correct region.
// Retry the request to the s3-external endpoint to yield a 307 redirect
// that we can then follow to the correct bucket location with the expected
// signing algorithm.
Logger.InfoFormat("Request {0}: the bucket you are attempting to access should be addressed using a region-specific endpoint."
+ " Additional calls will be made to attempt to determine the correct region to be used."
+ " For better performance configure your client to use the correct region.",
executionContext.RequestContext.RequestName);
var r = executionContext.RequestContext.Request;
var s3Uri = new AmazonS3Uri(r.Endpoint);
// since DNS resolved, yielding an auth error from the service,
// we're assuming we do not need to test (again) for dns compatibility
// on the bucket name
var tempEndpoint = string.Format(CultureInfo.InvariantCulture,
"https://{0}.{1}", s3Uri.Bucket, S3Constants.S3AlternateDefaultEndpoint);
r.Endpoint = new Uri(tempEndpoint);
if (serviceException.Message.Contains(AWS_KMS_Signature_Error))
{
r.UseSigV4 = true;
r.AuthenticationRegion = RegionEndpoint.USEast1.SystemName;
executionContext.RequestContext.IsSigned = false;
}
return(true);
}
}
}
return(base.RetryForException(executionContext, exception));
}
internal static async Task <bool> SharedRetryForExceptionAsync(Runtime.IExecutionContext executionContext, Exception exception,
Func <Runtime.IExecutionContext, Exception, bool?> retryForExceptionSync,
Func <Runtime.IExecutionContext, Exception, bool> baseRetryForException)
{
var syncResult = retryForExceptionSync(executionContext, exception);
if (syncResult.HasValue)
{
return(syncResult.Value);
}
else
{
var serviceException = exception as AmazonServiceException;
string correctedRegion = null;
AmazonS3Uri s3BucketUri;
if (AmazonS3Uri.TryParseAmazonS3Uri(executionContext.RequestContext.Request.Endpoint, out s3BucketUri))
{
var credentials = executionContext.RequestContext.ImmutableCredentials;
correctedRegion = await BucketRegionDetector.DetectMismatchWithHeadBucketFallbackAsync(s3BucketUri, serviceException, credentials).ConfigureAwait(false);
}
if (correctedRegion == null)
{
return(baseRetryForException(executionContext, exception));
}
else
{
// change authentication region of request and signal the handler to sign again with the new region
executionContext.RequestContext.Request.AuthenticationRegion = correctedRegion;
executionContext.RequestContext.IsSigned = false;
return(true);
}
}
}
/// <summary>
/// Return true if the request should be retried. Implements additional checks
/// specific to S3 on top of the checks in DefaultRetryPolicy.
/// </summary>
/// <param name="executionContext">Request context containing the state of the request.</param>
/// <param name="exception">The exception thrown by the previous request.</param>
/// <returns>Return true if the request should be retried.</returns>
public override bool RetryForException(Runtime.IExecutionContext executionContext, Exception exception)
{
var syncResult = RetryForExceptionSync(executionContext, exception);
if (syncResult.HasValue)
{
return(syncResult.Value);
}
else
{
var serviceException = exception as AmazonServiceException;
string correctedRegion = null;
AmazonS3Uri s3BucketUri;
if (AmazonS3Uri.TryParseAmazonS3Uri(executionContext.RequestContext.Request.Endpoint, out s3BucketUri))
{
var credentials = executionContext.RequestContext.ImmutableCredentials;
if (credentials != null)
{
correctedRegion = BucketRegionDetector.DetectMismatchWithHeadBucketFallback(s3BucketUri, serviceException, credentials);
}
}
if (correctedRegion == null)
{
return(base.RetryForException(executionContext, exception));
}
else
{
// change authentication region of request and signal the handler to sign again with the new region
executionContext.RequestContext.Request.AuthenticationRegion = correctedRegion;
executionContext.RequestContext.IsSigned = false;
return(true);
}
}
}
/// <summary>
/// Return true if the request should be retried. Implements additional checks
/// specific to S3 on top of the checks in StandardRetryPolicy.
/// </summary>
/// <param name="executionContext">Request context containing the state of the request.</param>
/// <param name="exception">The exception thrown by the previous request.</param>
/// <returns>Return true if the request should be retried.</returns>
public override async Task <bool> RetryForExceptionAsync(Runtime.IExecutionContext executionContext, Exception exception)
{
return(await AmazonS3RetryPolicy.SharedRetryForExceptionAsync(executionContext, exception, RetryForExceptionSync, base.RetryForException).ConfigureAwait(false));
}
/// <summary>
/// Perform the processor-bound portion of the RetryForException logic.
/// This is shared by the sync, async, and APM versions of the RetryForException method.
/// </summary>
/// <param name="executionContext"></param>
/// <param name="exception"></param>
/// <returns>a value if it can be determined, or null if the IO-bound calculations need to be done</returns>
public bool?RetryForExceptionSync(Runtime.IExecutionContext executionContext, Exception exception)
{
return(SharedRetryForExceptionSync(executionContext, exception, Logger, base.RetryForException));
}
/// <summary>
/// Return true if the request should be retried. Implements additional checks
/// specific to S3 on top of the checks in StandardRetryPolicy.
/// </summary>
/// <param name="executionContext">Request context containing the state of the request.</param>
/// <param name="exception">The exception thrown by the previous request.</param>
/// <returns>Return true if the request should be retried.</returns>
public override bool RetryForException(Runtime.IExecutionContext executionContext, Exception exception)
{
return(AmazonS3RetryPolicy.SharedRetryForException(executionContext, exception, RetryForExceptionSync, base.RetryForException));
}
