Fix DedicatedClusterSnapshotRestoreIT.testSnapshotWithStuckNode that is failing with reproducible seed

[cwperks]

Description

Fails consistently with:

./gradlew ':server:internalClusterTest' --tests "org.opensearch.snapshots.DedicatedClusterSnapshotRestoreIT.testSnapshotWithStuckNode" -Dtests.seed=565D3205AE4EEC96 -Dtests.security.manager=true -Dtests.jvm.argline="-XX:TieredStopAtLevel=1 -XX:ReservedCodeCacheSize=64m" -Dtests.locale=uz-Cyrl -Dtests.timezone=Australia/Victoria -Druntime.java=23 -i

This PR ensures that the generation in the ShardSnapshotStatus is not null in the case where the snapshot is aborted. Essentially the repository cleanup fails to cleanup files where a snapshot was aborted.

Related Issues

Resolves #15806

Check List

• Functionality includes testing.
• API changes companion pull request created, if applicable.
• Public documentation issue/PR created, if applicable.

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[github-actions]

❌ Gradle check result for de2f7a2: FAILURE

Please examine the workflow log, locate, and copy-paste the failure(s) below, then iterate to green. Is the failure a flaky test unrelated to your change?

[github-actions]

✅ Gradle check result for de2f7a2: SUCCESS

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 72.47%. Comparing base (e27cf58) to head (30f2b90).
Report is 2 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff              @@
##               main   #17389      +/-   ##
============================================
- Coverage     72.53%   72.47%   -0.06%     
+ Complexity    65814    65722      -92     
============================================
  Files          5311     5311              
  Lines        304945   304948       +3     
  Branches      44226    44226              
============================================
- Hits         221193   221017     -176     
- Misses        65619    65815     +196     
+ Partials      18133    18116      -17     

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[cwperks]

One thing I've noticed is the the shardCount is wrong for this seed. shardInfo.getShardCount() returns 1 when it should return 2 here.

status.generation() is returning null here and it returns the index name when the test is successful.

Status shows the following: ShardSnapshotStatus[state=FAILED, nodeId=6ROcJ0L_RFehM4-ZvkwNFg, reason=aborted, generation=null]

When the test is successful it returns: ShardSnapshotStatus[state=SUCCESS, nodeId=LlXDDnl8SOqPEsivPOCFbw, reason=null, generation=OdpXP3dbReumUYQ9l2zdWg]

[github-actions]

❌ Gradle check result for fe9d1e6: FAILURE

Please examine the workflow log, locate, and copy-paste the failure(s) below, then iterate to green. Is the failure a flaky test unrelated to your change?

[github-actions]

❌ Gradle check result for 96d866c: FAILURE

Please examine the workflow log, locate, and copy-paste the failure(s) below, then iterate to green. Is the failure a flaky test unrelated to your change?

[github-actions]

❌ Gradle check result for 96d866c: FAILURE

Please examine the workflow log, locate, and copy-paste the failure(s) below, then iterate to green. Is the failure a flaky test unrelated to your change?

[github-actions]

❌ Gradle check result for 96d866c: FAILURE

Please examine the workflow log, locate, and copy-paste the failure(s) below, then iterate to green. Is the failure a flaky test unrelated to your change?

[github-actions]

❌ Gradle check result for d123f8c: FAILURE

Please examine the workflow log, locate, and copy-paste the failure(s) below, then iterate to green. Is the failure a flaky test unrelated to your change?

[github-actions]

✅ Gradle check result for d123f8c: SUCCESS

[github-actions]

❌ Gradle check result for 30f2b90: FAILURE

Please examine the workflow log, locate, and copy-paste the failure(s) below, then iterate to green. Is the failure a flaky test unrelated to your change?

[github-actions]

❕ Gradle check result for 30f2b90: UNSTABLE

• TEST FAILURES:

      1 org.opensearch.snapshots.DedicatedClusterSnapshotRestoreIT.testSnapshotWithStuckNode
      1 org.opensearch.action.admin.cluster.node.tasks.ResourceAwareTasksTests.testTaskResourceTrackingDuringTaskCancellation

Please review all flaky tests that succeeded after retry and create an issue if one does not already exist to track the flaky failure.

[msfroh]

@cwperks -- I just got hit by this flaky test and was hoping that your PR will fix it. But, it looks like one of your runs yesterday failed with org.opensearch.snapshots.DedicatedClusterSnapshotRestoreIT.testSnapshotWithStuckNode.

Do you know if that's another issue unrelated to your fix? Does your fix make the test less flaky? I'm definitely willing to accept less flaky.

[cwperks]

@cwperks -- I just got hit by this flaky test and was hoping that your PR will fix it. But, it looks like one of your runs yesterday failed with org.opensearch.snapshots.DedicatedClusterSnapshotRestoreIT.testSnapshotWithStuckNode.

Do you know if that's another issue unrelated to your fix? Does your fix make the test less flaky? I'm definitely willing to accept less flaky.

The changes in this PR fix an issue with a reproducible seed which would certainly cut down on flakiness in this test case. I just looked at the failure in #17389 (comment), but I can't reproduce with the same seed from that run when running the test locally. I think the changes in this PR will reduce the flakiness, but looks like test is still susceptible to failing if the snapshot repository that is created in the test isn't cleaned up in time.

[cwperks]

@msfroh any concerns with this flaky test fix?