Description

Allow static agents to be deployed as a StatefulSet or as a DaemonSet.
Support specifying volumeClaimTemplates, which allow static agents to keep their identity at restart

Some value keys have been renamed for consistency.

Relevant issues

• fixes Persist /godata at static agent restart #111

Possible challenges

Keys that had deployment in their name have been changed to controller, this is a very minimal breaking change.
There are many other ways to write those keys, I await the maintainers' opinion.

Additional information

Because of the discussion in #111 I've kept the /godata persistence as a side effect of STS+volumeClaimTemplate support instead of implementing it as a first class feature.

Said persistence is achieved with (this will end up in the README and it's in commented values):

agent:
  controller:
    kind: "StatefulSet"
  persistence:
    claimTemplates:
      - metadata:
          name: godata
        spec:
          accessModes: ["ReadWriteOnce"]
          resources:
            requests:
              storage: SIZE
          storageClassName: NAME
    extraVolumeMounts:
      - name: godata
        mountPath: /godata

STS's podManagementPolicy is available since Kube 1.7, so there is no need to check capabilities.

Once the changes have been reviewed, iterated and approved I'll write out the Changelog changes.

Checklist

• Chart version bumped in Chart.yaml
• Any new variables have documentation and examples in values.yaml, even if commented out
• Any new variables added to the README.md
• Squash into a single commit (or explain why you'd prefer not to), except...
• ...additional commit added for CHANGELOG.md entry
• Helm lint + tests passing?