This change adds a mutex to the MachineController structure which is
used to gate access to the DeleteNodes function.
This is one in a series of PRs to mitigate kubernetes#3104
There might be adhoc environments where machineDeployments might not necessarily be available. This let the controller to remain functional for such scenarios.
This change adds detection for an environment variable to specify the group for the clusterapi resources. If the environment
variable `CAPI_GROUP` is specified, then it will
be used instead of the default.
This also decouples the API group from the version and let the latter to be discovered dynamically.
We index on providerID but it turns out that those values on node and
machine are not always consistent. Some encode region, some do not,
for example.
This commit normalizes all values through the normalizedProviderString().
To ensure that we catch all places I've introduced a new type and made
the find() functions take this new type in lieu of a string. Unit
tests have also been adjusted to introduce a 'test:///' prefix on the
providerID value to further validate the change.
This change allows CAPI to work out-of-the-box, assuming v1alpha2.
It's also reasonable to assert that this consistency should be
enforced elsewhere and to make this behaviour easily revertable I'm
leaving this as a separate commit in this patch series.
The autoscaler expects provider implementations nodeGroups to implement the Nodes() function to return the number of instances belonging to the group regardless of they have become a kubernetes node or not.
This information is then used for instance to realise about unregistered nodes bf3a9fb52e/cluster-autoscaler/clusterstate/clusterstate.go (L307-L311)
Michael McCune
Joel Speed
Enxebre
Andrew McDermott