Currently, when a k8s component is a DMaaP DR subscriber, the component container is started and its readiness verified by the k8s plugin before the DR subscriber is added to the DR feed by the DMaaP plugin.  (This is a carryover from an earlier native Docker implementation where the port address for the subscriber was assigned by Docker at deployment time and thus was not known until the container was launched.)

Certain k8s components are now using the "preferred subscriber" option.  These components need a full DMaaP subscriber configuration at startup, including the subscriber ID generated by DMaaP when the subscriber is added.   To support this, the subscriber needs to added (and the DMaaP information added to the component's configuration) before the component's container is started.

Doing this will require a change to the DMaaP plugin's type file and changes to the k8s plugin to make sure that the plugin has set up all of the subscriber information before the DMaaP plugin's add subscriber code is invoked.

Note that this new approach works well in settings where the component and the DR delivery node are in the same k8s cluster, as it is easy to determine a host/port combination to which DR can make a delivery.   Determining the host/port combination in a multi-k8s-cluster environment will depend on the underlying mechanisms used to support multi-k8s-cluster operation.