Reuse checksum on streaming request retries

Author: sbaluja

src/aws-cpp-sdk-core/include/aws/core/AmazonWebServiceRequest.h

@@ -35,6 +35,10 @@ namespace Aws
     typedef std::function<void(const AmazonWebServiceRequest&)> RequestRetryHandler;
     typedef std::function<void(const Aws::Http::HttpRequest&)> RequestSignedHandler;
 
+    struct RetryContext {
+      std::pair<Aws::String, std::shared_ptr<Aws::Utils::Crypto::Hash>> m_requestHash;
+    };
+
     /**
      * Base level abstraction for all modeled AWS requests
      */
@@ -222,7 +226,9 @@ namespace Aws
          */
         Aws::Set<Aws::Client::UserAgentFeature> GetUserAgentFeatures() const { return m_userAgentFeatures; }
 
-      inline virtual bool RequestChecksumRequired() const { return false; }
+        inline virtual bool RequestChecksumRequired() const { return false; }
+
+        mutable Aws::RetryContext m_retryContext;
     protected:
         /**
          * Default does nothing. Override this to convert what would otherwise be the payload of the

src/aws-cpp-sdk-core/include/smithy/client/features/ChecksumInterceptor.h

@@ -84,42 +84,49 @@ class ChecksumInterceptor : public smithy::interceptor::Interceptor {
         // AwsAuthSigner decide it.
         if (request.IsStreaming() && checksumValueAndAlgorithmProvided) {
           addChecksumFeatureForChecksumName(checksumAlgorithmName, request);
-          const auto hash = Aws::MakeShared<PrecalculatedHash>(AWS_SMITHY_CLIENT_CHECKSUM, checksumHeader->second);
-          httpRequest->SetRequestHash(checksumAlgorithmName, hash);
+          if (httpRequest->GetRequestHash().second == nullptr) {
+            const auto hash = Aws::MakeShared<PrecalculatedHash>(AWS_SMITHY_CLIENT_CHECKSUM, checksumHeader->second);
+            httpRequest->SetRequestHash(checksumAlgorithmName, hash);
+          }
         } else if (checksumValueAndAlgorithmProvided) {
           httpRequest->SetHeaderValue(checksumType, checksumHeader->second);
         } else if (checksumAlgorithmName == "crc64nvme") {
           request.AddUserAgentFeature(Aws::Client::UserAgentFeature::FLEXIBLE_CHECKSUMS_REQ_CRC64);
           if (request.IsStreaming()) {
-            httpRequest->SetRequestHash(checksumAlgorithmName, Aws::MakeShared<CRC64>(AWS_SMITHY_CLIENT_CHECKSUM));
+            if (httpRequest->GetRequestHash().second == nullptr)
+              httpRequest->SetRequestHash(checksumAlgorithmName, Aws::MakeShared<CRC64>(AWS_SMITHY_CLIENT_CHECKSUM));
           } else {
             httpRequest->SetHeaderValue(checksumType, HashingUtils::Base64Encode(HashingUtils::CalculateCRC64(*(GetBodyStream(request)))));
           }
         } else if (checksumAlgorithmName == "crc32") {
           request.AddUserAgentFeature(Aws::Client::UserAgentFeature::FLEXIBLE_CHECKSUMS_REQ_CRC32);
           if (request.IsStreaming()) {
-            httpRequest->SetRequestHash(checksumAlgorithmName, Aws::MakeShared<CRC32>(AWS_SMITHY_CLIENT_CHECKSUM));
+            if (httpRequest->GetRequestHash().second == nullptr)
+              httpRequest->SetRequestHash(checksumAlgorithmName, Aws::MakeShared<CRC32>(AWS_SMITHY_CLIENT_CHECKSUM));
           } else {
             httpRequest->SetHeaderValue(checksumType, HashingUtils::Base64Encode(HashingUtils::CalculateCRC32(*(GetBodyStream(request)))));
           }
         } else if (checksumAlgorithmName == "crc32c") {
           request.AddUserAgentFeature(Aws::Client::UserAgentFeature::FLEXIBLE_CHECKSUMS_REQ_CRC32C);
           if (request.IsStreaming()) {
-            httpRequest->SetRequestHash(checksumAlgorithmName, Aws::MakeShared<CRC32C>(AWS_SMITHY_CLIENT_CHECKSUM));
+            if (httpRequest->GetRequestHash().second == nullptr)
+              httpRequest->SetRequestHash(checksumAlgorithmName, Aws::MakeShared<CRC32C>(AWS_SMITHY_CLIENT_CHECKSUM));
           } else {
             httpRequest->SetHeaderValue(checksumType, HashingUtils::Base64Encode(HashingUtils::CalculateCRC32C(*(GetBodyStream(request)))));
           }
         } else if (checksumAlgorithmName == "sha256") {
           request.AddUserAgentFeature(Aws::Client::UserAgentFeature::FLEXIBLE_CHECKSUMS_REQ_SHA256);
           if (request.IsStreaming()) {
-            httpRequest->SetRequestHash(checksumAlgorithmName, Aws::MakeShared<Sha256>(AWS_SMITHY_CLIENT_CHECKSUM));
+            if (httpRequest->GetRequestHash().second == nullptr)
+              httpRequest->SetRequestHash(checksumAlgorithmName, Aws::MakeShared<Sha256>(AWS_SMITHY_CLIENT_CHECKSUM));
           } else {
             httpRequest->SetHeaderValue(checksumType, HashingUtils::Base64Encode(HashingUtils::CalculateSHA256(*(GetBodyStream(request)))));
           }
         } else if (checksumAlgorithmName == "sha1") {
           request.AddUserAgentFeature(Aws::Client::UserAgentFeature::FLEXIBLE_CHECKSUMS_REQ_SHA1);
           if (request.IsStreaming()) {
-            httpRequest->SetRequestHash(checksumAlgorithmName, Aws::MakeShared<Sha1>(AWS_SMITHY_CLIENT_CHECKSUM));
+            if (httpRequest->GetRequestHash().second == nullptr)
+              httpRequest->SetRequestHash(checksumAlgorithmName, Aws::MakeShared<Sha1>(AWS_SMITHY_CLIENT_CHECKSUM));
           } else {
             httpRequest->SetHeaderValue(checksumType, HashingUtils::Base64Encode(HashingUtils::CalculateSHA1(*(GetBodyStream(request)))));
           }

src/aws-cpp-sdk-core/source/client/AWSClient.cpp

@@ -389,6 +389,13 @@ HttpResponseOutcome AWSClient::AttemptExhaustively(const Aws::Http::URI& uri,
         {
             newUri.SetAuthority(newEndpoint);
         }
+
+        // Save checksum information from the original request if we haven't already - safe to assume that the checksum has been finalized, since we have sent and received a response
+        if (request.m_retryContext.m_requestHash.second == nullptr) {
+          auto originalRequestHash = httpRequest->GetRequestHash();
+          request.m_retryContext.m_requestHash = originalRequestHash;
+        }
+
         httpRequest = CreateHttpRequest(newUri, method, request.GetResponseStreamFactory());
 
         httpRequest->SetHeaderValue(Http::SDK_INVOCATION_ID_HEADER, invocationId);
@@ -920,6 +927,12 @@ void AWSClient::BuildHttpRequest(const Aws::AmazonWebServiceRequest& request, co
     httpRequest->SetContinueRequestHandle(request.GetContinueRequestHandler());
     httpRequest->SetServiceSpecificParameters(request.GetServiceSpecificParameters());
     request.AddQueryStringParameters(httpRequest->GetUri());
+
+    // check for retry context, if present use it
+    if (request.m_retryContext.m_requestHash.second != nullptr) {
+      const auto hash = Aws::MakeShared<Aws::Utils::Crypto::PrecalculatedHash>(AWS_SMITHY_CLIENT_CHECKSUM, HashingUtils::Base64Encode(request.m_retryContext.m_requestHash.second->GetHash().GetResult()));
+      httpRequest->SetRequestHash(request.m_retryContext.m_requestHash.first, hash);
+    }
 }
 
 Aws::String AWSClient::GeneratePresignedUrl(const Aws::Http::URI& uri, Aws::Http::HttpMethod method, long long expirationInSeconds, const std::shared_ptr<Aws::Http::ServiceSpecificParameters> serviceSpecificParameter)