* S3: add KeyTooLongError error code
Add ErrKeyTooLongError (HTTP 400, code "KeyTooLongError") to match the
standard AWS S3 error for object keys that exceed length limits.
* S3: fix silent PutObject failure when entry name exceeds max_file_name_length
putToFiler called client.CreateEntry() directly and discarded the gRPC
response. The filer embeds application errors like "entry name too long"
in resp.Error (not as gRPC transport errors), so the error was silently
swallowed and clients received HTTP 200 with an ETag for objects that
were never stored.
Switch to the filer_pb.CreateEntry() helper which properly checks
resp.Error, and map "entry name too long" to KeyTooLongError (HTTP 400).
To avoid fragile string parsing across the gRPC boundary, define shared
error message constants in weed/util/constants and use them in both the
filer (producing errors) and S3 API (matching errors). Switch
filerErrorToS3Error to use strings.Contains/HasSuffix with these
constants so matches work regardless of any wrapper prefix. Apply
filerErrorToS3Error to the mkdir path for directory markers.
Fixes#8759
* S3: enforce 1024-byte maximum object key length
AWS S3 limits object keys to 1024 bytes. Add early validation on write
paths (PutObject, CopyObject, CreateMultipartUpload) to reject keys
exceeding the limit with the standard KeyTooLongError (HTTP 400).
The key length check runs before bucket auto-creation to prevent
overlong keys from triggering unnecessary side effects.
Also use filerErrorToS3Error for CopyObject's mkFile error paths so
name-too-long errors from the filer return KeyTooLongError instead of
InternalError.
Ref #8758
* S3: add handler-level tests for key length validation and error mapping
Add tests for filerErrorToS3Error mapping "entry name too long" to
KeyTooLongError, including a regression test for the CreateEntry-prefixed
"existing ... is a directory" form. Add handler-level integration tests
that exercise PutObjectHandler, CopyObjectHandler, and
NewMultipartUploadHandler via httptest, verifying HTTP 400 and
KeyTooLongError XML response for overlong keys and acceptance of keys at
the 1024-byte limit.
Chris Lu
2877febd73