Snapshot _status API: Include in-progress snapshots in total shard count and index filter

[ltaragi]

Description

• In [SnapshotV2] Snapshot Status API changes #15409,

  • We added changes to impose an upper limit on the number of shards that can be included in the snapshot status API's response with the help of snapshot.max_shards_allowed_in_status_api dynamic cluster setting.
  • We also added a variant of the API to pass a comma-separated list of index names (for a singular snapshot only) to manage the shard count in its response

• We also need to extend the same to the shards contributed by running snapshots in the APIs response.

  • While calculating the total number of required shards in the response, the shards of running snapshots must also be accounted for.
  • Similarly, users should be able to pass an index list for a running snapshot and get status for only the relevant indices in the response

• Added stricter checks for when to allow an index-filter (particular snapshot in a particular repository):

  • We can invalidate requests with _all value for repository or snapshot parameter of the API request
  • _all value for index parameter results to no index-filter at all

• In case of index-filter and ignore_unavailable as true, the missing indices should be removed from the set of indices which ultimately comprise the final response

• Improved the exception messages for clarity

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 eb39c25: SUCCESS

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 88 lines in your changes missing coverage. Please review.

Project coverage is 71.96%. Comparing base (ad7f9e7) to head (57cfd5f).
Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
...apshots/status/TransportSnapshotsStatusAction.java	0.00%	78 Missing ⚠️
...uster/snapshots/status/SnapshotsStatusRequest.java	0.00%	8 Missing ⚠️
...ction/admin/cluster/RestSnapshotsStatusAction.java	0.00%	1 Missing and 1 partial ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##               main   #16394      +/-   ##
============================================
- Coverage     72.05%   71.96%   -0.09%     
+ Complexity    64861    64793      -68     
============================================
  Files          5309     5309              
  Lines        302734   302785      +51     
  Branches      43733    43750      +17     
============================================
- Hits         218134   217901     -233     
- Misses        66731    67003     +272     
- Partials      17869    17881      +12     

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[github-actions]

❌ Gradle check result for ef2af69: 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 5146d60: 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?

[ltaragi]

❌ Gradle check result for 5146d60: 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?

Flaky test #15807

[github-actions]

❌ Gradle check result for 5146d60: 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 57cfd5f: SUCCESS