Attributes of Tendrl objects should be watchable

[r0h4n]

• Add "watch_attrs" (type: list) to Tendrl definition schema for the Object

  • eg:

    objects: 
    Cluster:
    enabled: True
    help: "Represents a cluster"
    list: /clusters
    value: clusters/$TendrlContext.integration_id
    watch_attrs: 
          - errors
          - status

• In Services (tendrl-node-agent, tendrl-gluster-integration etc) that can .save() an object, a watcher thread will be created per attribute of that instance of the object.

eg: /clusters/asdadwwasd/status (creates 1 watcher per service for given integration_id/status)

[r0h4n]

Target is to generate status change alerts for Volumes, Clusters, Bricks, Nodes via the object.watch_attrs functionality.

@shtripat @Tendrl/admins any other suggestions?

[shtripat]

Agree as that would be best place to do this.