A PUT which failed part way through removed the object at the
destination key. As well as differing from real S3 (where a failed PUT
never affects the stored object), this raced with the client's
automatic retry of the same PUT: the retry stored the object and
returned 200 OK, then the failed first attempt's cleanup deleted it,
silently losing an acknowledged upload. The interrupted upload could
also be committed as a truncated object, since closing the write handle
gave the streaming upload a clean end of stream.
Now a failed or interrupted PUT never disturbs the object at the key:
- The object at the key is never removed on error.
- On backends where a partial upload is visible at its final name
(PartialUploads), and when the VFS cache mode is writes or above, the
upload is written to a temporary object which is renamed into place
on success and removed on failure, as streamed multipart uploads
already do. Backends which upload atomically are still streamed
straight to the destination.
- An interrupted or short body fails the upload via
WriteFileHandle.CloseWithError instead of committing truncated data,
and a body which ends cleanly short of its declared size is rejected
with IncompleteBody.
Nick Craig-Wood
84298fc090