fix: add gcs compatibility flag to fix s3proxy GCS SigV4 signature mismatch#2045
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benmcclelland merged 1 commit intomainfrom Apr 15, 2026
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fix: add gcs compatibility flag to fix s3proxy GCS SigV4 signature mismatch#2045benmcclelland merged 1 commit intomainfrom
benmcclelland merged 1 commit intomainfrom
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…smatch The AWS SDK v2 includes Accept-Encoding in SigV4 signed headers which causes GCS to return a SignatureDoesNotMatch error because GCS rewrites that header internally before verifying the signature. Add a --gcs-compatibility / VGW_S3_GCS_COMPATIBILITY option for the s3proxy backend that injects two Smithy finalize-layer middlewares: one removes Accept-Encoding from the request immediately before the Signing step, and a second restores it after signing so the header is still sent on the wire. see: aws/aws-sdk-go-v2#1816 This can be removed once GCS fixes this incompatibility.
niksis02
approved these changes
Apr 15, 2026
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The AWS SDK v2 includes Accept-Encoding in SigV4 signed headers which causes GCS to return a SignatureDoesNotMatch error because GCS rewrites that header internally before verifying the signature.
Add a --gcs-compatibility / VGW_S3_GCS_COMPATIBILITY option for the s3proxy backend that injects two Smithy finalize-layer middlewares: one removes Accept-Encoding from the request immediately before the Signing step, and a second restores it after signing so the header is still sent on the wire.
see: aws/aws-sdk-go-v2#1816
This can be removed once GCS fixes this incompatibility.