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.
Optionally allows customers to enable
- Enable an external cache to catch GET/HEAD responses
- Enable skipping disks that are slow to respond in GET/HEAD
when we have already achieved a quorum
resync status may not be upto-date by
the time the resync is over due to how
the timer is triggered.
diff is sufficient to know if replication
happened or not.
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.