STORM-3655: Worker should die if its assignment has changed

[kishorvpatil]

What is the purpose of the change

The assignment change should lead to worker suicide. This is specially critical if Supervisor is down for some reason

How was the change tested

1. Launcher WordCountTopology, wait for worker to start
2. Stop the supervisor
3. Re-balance topology so worker is assigned to next supervisor
4. Worker should kill itself with worker.log entries similar to below.

2020-06-22 06:55:40.527 o.a.s.d.w.WorkerState refresh-connections-timer [INFO] Found conflicting assignments. We shouldn't be alive! Assigned: [[-1, -1]], Current: [[-1, -1], [14, 14], [12, 12], [10, 10], [8, 8], [6, 6], [4, 4], [2, 2], [7, 7], [5, 5], [3, 3], [1, 1], [13, 13], [11, 11], [9, 9]]
2020-06-22 06:55:40.529 o.a.s.u.Utils refresh-connections-timer [ERROR] Halting process: Worker died
java.lang.RuntimeException: Halting process: Worker died
        at org.apache.storm.utils.Utils.exitProcess(Utils.java:518) ~[storm-client-2.3.0.y.jar:2.3.0.y]
        at org.apache.storm.daemon.worker.WorkerState.suicideIfLocalAssignmentsChanged(WorkerState.java:390) ~[storm-client-2.3.0.y.jar:2.3.0.y]
        at org.apache.storm.daemon.worker.WorkerState.refreshConnections(WorkerState.java:421) ~[storm-client-2.3.0.y.jar:2.3.0.y]
        at org.apache.storm.StormTimer$1.run(StormTimer.java:110) [storm-client-2.3.0.y.jar:2.3.0.y]
        at org.apache.storm.StormTimer$StormTimerTask.run(StormTimer.java:226) [storm-client-2.3.0.y.jar:2.3.0.y]
2020-06-22 06:55:40.552 o.a.s.d.w.Worker Thread-32 [INFO] Shutting down worker fwc2-1-1592662435 44c0bd8e-bd3c-4317-b09f-1f0deb3f2a7c 6700

[Ethanlm]

Looks good to me. Left a minor comment.

[Ethanlm]

We can place this as earlier as possible in this refreshConnections method.

[kishorvpatil]

Addressed

[Ethanlm]

+1