Glacier Request Body Checksum

[awslabs]

Glacier Request Body Checksum

[aajtodd]

https://docs.aws.amazon.com/amazonglacier/latest/dev/api-common-request-headers.html

[aajtodd]

https://docs.aws.amazon.com/amazonglacier/latest/dev/checksum-calculations.html

example's from Go V2:

• (runtime): https://github.com/aws/aws-sdk-go-v2/blob/main/service/glacier/internal/customizations/treehash.go
• (codegen): https://github.com/aws/aws-sdk-go-v2/blob/main/codegen/smithy-aws-go-codegen/src/main/java/software/amazon/smithy/aws/go/codegen/customization/GlacierCustomizations.java#L24

[aajtodd]

estimate 3 weeks if we need to implement the checksum (sha256) capability in the runtime.
estimate 2 week if checksum capability has been added to the runtime already

Implementing the tree hash functionality as a middleware should be relatively straightforward given the raw hashing capabilities exist in the runtime (see smithy-lang/smithy-kotlin#382)

The x-amz-content-sha256 can be added by customizing the signing middleware config like required for S3:

            install(AwsSigV4SigningMiddleware) {
                credentialsProvider = config.credentialsProvider ?: DefaultChainCredentialsProvider()
                signingService = "s3"
                signedBodyHeaderType = AwsSignedBodyHeaderType.X_AMZ_CONTENT_SHA256
            }