precondition check was being honored before, validating
if anonymous access is allowed on the metadata of an
object, leading to metadata disclosure of the following
headers.
```
Last-Modified
Etag
x-amz-version-id
Expires:
Cache-Control:
```
although the information presented is minimal in nature,
and of opaque nature. It still simply discloses that an
object by a specific name exists or not without even having
enough permissions.
instead upon any error in renameData(), we still
preserve the existing dataDir in some form for
recoverability in strange situations such as out
of disk space type errors.
Bonus: avoid running list and heal() instead allow
versions disparity to return the actual versions,
uuid to heal. Currently limit this to 100 versions
and lesser disparate objects.
an undo now reverts back the xl.meta from xl.meta.bkp
during overwrites on such flaky setups.
Bonus: Save N depth syscalls via skipping the parents
upon overwrites and versioned updates.
Flaky setup examples are stretch clusters with regular
packet drops etc, we need to add some defensive code
around to avoid dangling objects.
The middleware sets up tracing, throttling, gzipped responses and
collecting API stats.
Additionally, this change updates the names of handler functions in
metric labels to be the same as the name derived from Go lang reflection
on the handler name.
The metric api labels are now stored in memory the same as the handler
name - they will be camelcased, e.g. `GetObject` instead of `getobject`.
For compatibility, we lowercase the metric api label values when emitting the metrics.
GetActualSize() was heavily relying on o.Parts()
to be non-empty to figure out if the object is multipart or not,
However, we have many indicators of whether an object is multipart
or not.
Blindly assuming that o.Parts == nil is not a multipart, is an
incorrect expectation instead, multipart must be obtained via
- Stored metadata value indicating this is a multipart encrypted object.
- Rely on <meta>-actual-size metadata to get the object's actual size.
This value is preserved for additional reasons such as these.
- ETag != 32 length
The bottom line is delete markers are a nuisance,
most applications are not version aware and this
has simply complicated the version management.
AWS S3 gave an unnecessary complication overhead
for customers, they need to now manage these
markers by applying ILM settings and clean
them up on a regular basis.
To make matters worse all these delete markers
get replicated as well in a replicated setup,
requiring two ILM settings on each site.
This PR is an attempt to address this inferior
implementation by deviating MinIO towards an
idempotent delete marker implementation i.e
MinIO will never create any more than single
consecutive delete markers.
This significantly reduces operational overhead
by making versioning more useful for real data.
This is an S3 spec deviation for pragmatic reasons.
The current code considers a pool with all root disks to be as part
of a testing environment even if there are other pools with mounted
disks. This will result to illegitimate writing in root disks.
Fix this by simplifing the logic: require MINIO_CI_CD in order to skip
root disk check.
data shards were wrong due to a healing bug
reported in #13803 mainly with unaligned object
sizes.
This PR is an attempt to automatically avoid
these shards, with available information about
the `xl.meta` and actually disk mtime.
