S3: compute request checksums only when required#42
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Since service/s3 v1.73.0 the SDK computes CRC32 checksums on PUT/multipart by default, breaking non-AWS S3-compatible backends that reject the parts. Set RequestChecksumCalculation to WhenRequired so no AWS_REQUEST_CHECKSUM_CALCULATION env var workaround is needed. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
UlysseCorbeil
approved these changes
Jul 9, 2026
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Problem
AWS SDK Go v2
service/s3≥ v1.73.0 computes CRC32 request checksums on PUT/multipart uploads by default. Non-AWS S3-compatible backends (MinIO, Ceph, GCS-S3, etc.) reject those parts, so uploads fail. Customers had to work around it with the env varAWS_REQUEST_CHECKSUM_CALCULATION=when_required.Ref: aws/aws-sdk-go-v2#2960
Fix
Set
o.RequestChecksumCalculation = aws.RequestChecksumCalculationWhenRequiredon the S3 client — the programmatic equivalent of the env var. Reverts to the pre-v1.73.0 behavior (checksum only when the operation requires it), no ops workaround needed.The existing
DisableLogOutputChecksumValidationSkippedonly silenced GET-side warning logs; it never touched request-side checksum calculation.🤖 Generated with Claude Code