fixup!: #15981 Missing completion reports on index_parallel tasks

[adithyachakilam]

Description

Fixed the bug where completion task reports are not being generated on index_parallel tasks.

The fix made in #15981 misses to call the writeCompletionReports inside ParallelIndexSupervisorTask#runSequential.

Also, this PR tries to address the comments made on #15981 and #15930 after merged.

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Key changed/added classes in this PR

• CompactionTask
• IndexTask
• ParallelIndexSupervisorTask

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This PR has:

• been self-reviewed.
  • using the concurrency checklist (Remove this item if the PR doesn't have any relation to concurrency.)
• added documentation for new or modified features or behaviors.
• a release note entry in the PR description.
• added Javadocs for most classes and all non-trivial methods. Linked related entities via Javadoc links.
• added or updated version, license, or notice information in licenses.yaml
• added comments explaining the "why" and the intent of the code wherever would not be obvious for an unfamiliar reader.
• added unit tests or modified existing tests to cover new code paths, ensuring the threshold for code coverage is met.
• added integration tests.
• been tested in a test Druid cluster.

[kfaraz]

Thanks for the quick fix, @adithyachakilam . I have left a few comments.

[georgew5656]

is this actually the behavior we want? it seems to contradict the behavior of other situations where we run a task inside another task where we expect the parent task to write its own reports

[georgew5656]

is this actually the behavior we want? it seems to contradict the behavior of other situations where we run a task inside another task where we expect the parent task to write its own reports

looking at the code it seems to me all the other branches in ParallelIndexSupervisorTask call writeCompletionReports using the task report of the subtask generated (runRangePartitionMultiPhaseParallel, runSinglePhaseParallel, runHashPartitionMultiPhaseParallel)

I see there's already this code

    if (currentSubTaskHolder.setTask(sequentialIndexTask)
        && sequentialIndexTask.isReady(toolbox.getTaskActionClient())) {
      TaskStatus status = sequentialIndexTask.run(toolbox);
      completionReports = sequentialIndexTask.getCompletionReports();
      return status;
    } else {
      String msg = "Task was asked to stop. Finish as failed";
      LOG.info(msg);
      return TaskStatus.failure(getId(), msg);
    }

shouldn't we just call writeCompletionReports here instead?

[adithyachakilam]

@georgew5656, That actually makes sense, fixed it!

[kfaraz]

LGTM