When updating node labels and annotations use JSON patches instead of
doing a read-modify-write on the whole node object. Patching is already
being used in managing extended resources so some of the existing code
was re-usable.
This patch should mitigate the problem of node update failures caused by
race conditions (a change in the node object between our read and write)
resulting e.g. in errors/restarts in nfd worker pods.
A new sub-command like flag for cleaning up a cluster. When --prune is
specified nfd-master removes all NFD related labels, annotations and
extended resources from all nodes of the cluster and exits.
This should help undeployment of NFD and be useful for development.
Extend the FeatureSource interface with new methods for configuration
handling. This enables easier on-the fly reconfiguration of the
feature sources. Further, it simplifies adding config support to feature
sources in the future. Stub methods are added to sources that do not
currently have any configurability.
The patch fixes some (corner) cases with the overrides (--options)
handling, too:
- Overrides were not applied if config file was missing or its parsing
failed
- Overrides for a certain source did not have effect if an empty config
for the source was specified in the config file. This was caused by
the first pass of parsing (config file) setting a nil pointer to the
source-specific config, effectively detaching it from the main config.
The second pass would then create a new instance of the source
specific config, but, this was not visible in the feature source, of
course.
This adds support for making selected labels extended resources.
Labels which have integer values, can be promoted to Kubernetes extended
resources by listing them to the added command line flag
`--resource-labels`. These labels won't then show in the node label
section, they will appear only as extended resources.
Signed-off-by: Ukri Niemimuukko <ukri.niemimuukko@intel.com>