Summary

NIFI-15655 - Flaky System Test FlowSynchronizationIT.testUnnecessaryProcessorsAndConnectionsRemoved

[ERROR] Tests run: 14, Failures: 0, Errors: 1, Skipped: 0, Time elapsed: 382.2 s <<< FAILURE! -- in org.apache.nifi.tests.system.clustering.FlowSynchronizationIT
[ERROR] org.apache.nifi.tests.system.clustering.FlowSynchronizationIT.testUnnecessaryProcessorsAndConnectionsRemoved -- Time elapsed: 312.5 s <<< ERROR!
java.util.concurrent.TimeoutException: testUnnecessaryProcessorsAndConnectionsRemoved() timed out after 5 minutes
	at java.base/java.util.ArrayList.forEach(ArrayList.java:1596)
	at java.base/java.util.ArrayList.forEach(ArrayList.java:1596)
	Suppressed: java.lang.InterruptedException: sleep interrupted
		at java.base/java.lang.Thread.sleep0(Native Method)
		at java.base/java.lang.Thread.sleep(Thread.java:509)
		at org.apache.nifi.tests.system.NiFiSystemIT.waitFor(NiFiSystemIT.java:420)
		at org.apache.nifi.tests.system.NiFiSystemIT.waitFor(NiFiSystemIT.java:407)
		at org.apache.nifi.tests.system.clustering.FlowSynchronizationIT.testUnnecessaryProcessorsAndConnectionsRemoved(FlowSynchronizationIT.java:718)

During the disconnect/reconnect cycle, ZooKeeper leader election can transiently return an address without a port. Previously, this caused an ArrayIndexOutOfBoundsException — which, while caught by HeartbeatSendTask's catch (Throwable), produced an opaque error.

With this change, both layers now throw a proper ProtocolException with a clear message. The ProtocolException is still caught by the same catch (Throwable) handler in HeartbeatSendTask.run(), the heartbeat task continues running, and the next cycle succeeds once leader election stabilizes. The clearer exception type and message makes the transient condition easier to diagnose in logs.

Modified some tests to improve reliability and have the proper wait conditions.

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  • JDK 21
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