tracking: re-enable SeaweedFS conditional stat/read tests after S3 parity fix

[Xuanwo]

Summary

Track a SeaweedFS S3 compatibility gap for conditional stat and read on a missing object. When If-Match contains a valid ETag obtained from another object, or when If-Unmodified-Since is set, Amazon S3 preserves missing-object semantics while SeaweedFS returns 412 PreconditionFailed.

This is a SeaweedFS S3 parity issue, not an OpenDAL S3 capability limitation.

Verified behavior

Reproduced with AWS CLI requests against SeaweedFS 4.40 and the latest release, 4.44. The If-Match condition used a valid ETag returned after creating another object in the same bucket.

Backend	Version	HEAD missing object	GET missing object
AWS S3	live service, OpenDAL behavior CI	NotFound	NotFound
SeaweedFS	4.40	412 PreconditionFailed	412 PreconditionFailed
SeaweedFS	4.44	412 PreconditionFailed	412 PreconditionFailed

Both SeaweedFS versions return 404 / NoSuchKey for the same missing object when no conditional header is present. SeaweedFS master still explicitly maps a missing entry with If-Match or If-Unmodified-Since to ErrPreconditionFailed.

Upstream report: seaweedfs/seaweedfs#10984

OpenDAL handling

OpenDAL's portable stat/read contract preserves NotFound when the target does not exist, including when if_match or if_unmodified_since is set. The S3 backend satisfies this contract against the live AWS service and should continue advertising these capabilities.

Until SeaweedFS matches AWS S3, its behavior-test configuration should override only these fixture capabilities:

stat_with_if_match=false
stat_with_if_unmodified_since=false
read_with_if_match=false
read_with_if_unmodified_since=false

Do not disable the S3 backend capabilities globally. Do not add a client-side existence probe: it would add another request and introduce a time-of-check/time-of-use race.

Current override:

opendal/.github/services/s3/seaweedfs_s3/action.yml

Line 38 in 844ef59

OPENDAL_TEST_CAPABILITY_OVERRIDES=stat_with_version=false,read_with_version=false,delete_with_version=false,list_with_versions=false,list_with_deleted=false,copy_with_source_version=false,restore=false,restore_with_version=false,restore_with_if_not_exists=false,write_can_append=false,stat_with_if_match=false,stat_with_if_unmodified_since=false,read_with_if_match=false,read_with_if_unmodified_since=false

Completion criteria

• SeaweedFS releases a fix for s3: conditional HeadObject/GetObject returns 412 for missing objects seaweedfs/seaweedfs#10984.
• OpenDAL updates its SeaweedFS behavior-test image to a fixed release.
• Missing-target conditional stat and read behavior tests pass against SeaweedFS for both If-Match and If-Unmodified-Since.
• The four SeaweedFS-only capability overrides are removed.

Related to #8168 and #8172.

AI assisted with actual-service reproduction, source verification, and drafting. The contributor directed the scope and conclusion.

[Xuanwo]

Thank you @chrislusf a lot for the quick fix! I'm guessing we can enable this check once SeaweedFS had a new release?