Add spec for cluster stats metric and index_metric filter paths.

[SwethaGuptha]

Description

Adding specs for path /_cluster/stats/{metric}/nodes/{nodeId} and /_cluster/stats/{metric}/{index_metric}/nodes/{nodeId} in cluster/stats API. With opensearch-project/OpenSearch#15938, the cluster/stats API will have filtering support that will allow the clients to fetch only specific metrics from cluster/stats instead of all metrics.

Issues Resolved

List any issues this PR will resolve, e.g. Closes [...].

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[github-actions]

Changes Analysis

Commit SHA: 3ceb510
Comparing To SHA: fce5721

API Changes

Summary

├─┬Paths
│ ├──[➕] path (1840:3)
│ └──[➕] path (1862:3)
└─┬Components
  ├──[➕] parameters (17278:7)
  ├──[➕] parameters (17288:7)
  ├──[➕] schemas (47763:7)
  ├──[➕] schemas (47792:7)
  ├─┬cluster.stats___StatsResponseBase
  │ ├─┬ALLOF
  │ │ └──[🔀] $ref (52964:13)❌ 
  │ └─┬ALLOF
  │   └──[🔀] $ref (47850:11)❌ 
  ├─┬cluster.stats___ClusterNodes
  │ ├──[➖] required (47479:11)❌ 
  │ ├──[➖] required (47480:11)❌ 
  │ ├──[➖] required (47483:11)❌ 
  │ ├──[➖] required (47485:11)❌ 
  │ ├──[➖] required (47486:11)❌ 
  │ ├──[➖] required (47487:11)❌ 
  │ ├──[➖] required (47478:11)❌ 
  │ ├──[➖] required (47481:11)❌ 
  │ ├──[➖] required (47482:11)❌ 
  │ ├──[➖] required (47484:11)❌ 
  │ └──[➖] required (47477:11)❌ 
  └─┬cluster.stats___ClusterIndices
    ├──[➖] required (47263:11)❌ 
    ├──[➖] required (47261:11)❌ 
    ├──[➖] required (47262:11)❌ 
    ├──[➖] required (47265:11)❌ 
    ├──[➖] required (47266:11)❌ 
    ├──[➖] required (47267:11)❌ 
    ├──[➖] required (47268:11)❌ 
    ├──[➖] required (47269:11)❌ 
    ├──[➖] required (47260:11)❌ 
    └──[➖] required (47264:11)❌ 

Document Element	Total Changes	Breaking Changes
components	27	25
paths	2	0

• ❌ BREAKING Changes: 25 out of 29
• Modifications: 2
• Removals: 21
• Additions: 6
• Breaking Removals: 21
• Breaking Modifications: 2

Report

The full API changes report is available at: https://github.com/opensearch-project/opensearch-api-specification/actions/runs/11826040133/artifacts/2184467167

API Coverage

	Before	After	Δ
Covered (%)	588 (57.59 %)	588 (57.59 %)	0 (0 %)
Uncovered (%)	433 (42.41 %)	433 (42.41 %)	0 (0 %)
Unknown	40	42	2

[dblock]

Looking good.

1. Bump the SHA for a more recent build of 2.18 and 3.0 in https://github.com/opensearch-project/opensearch-api-specification/blob/main/.github/workflows/test-spec.yml#L45 until tests pass.
2. Add to CHANGELOG.

[dblock]

@SwethaGuptha Looks like the build has other problems (missing other plugins like SQL and ISM). This is a known and rather annoying problem, 3.x builds don't always have everything. You should chase what's broken in OpenSearch main distribution.

I opened opensearch-project/opensearch-build#5130 to see what the infra team says about this (cc: @gaiksaya).

@gaiksaya

[SwethaGuptha]

@SwethaGuptha Looks like the build has other problems (missing other plugins like SQL and ISM). This is a known and rather annoying problem, 3.x builds don't always have everything. You should chase what's broken in OpenSearch main distribution.

I opened opensearch-project/opensearch-build#5130 to see what the infra team says about this (cc: @gaiksaya).

@gaiksaya

Thanks @dblock for creating the issue. Did the tests work for v#3.0.0 previously? I see there are some failures from core OS as well. Also,I see the latest image available for v#3.0 is from eight days ago, do you know what cadence is followed for updating the version image?

[dblock]

Thanks @dblock for creating the issue. Did the tests work for v#3.0.0 previously? I see there are some failures from core OS as well.

Yes, the failure on main right now came from #625 and will get fixed soon.

Also,I see the latest image available for v#3.0 is from eight days ago, do you know what cadence is followed for updating the version image?

I think they try to build one daily, but it doesn't always work :(

[gaiksaya]

I opened opensearch-project/opensearch-build#5130 to see what the infra team says about this (cc: @gaiksaya).

@gaiksaya

Will add more details to the issue but docker image is build using tarball. And all the distributions contains distribution manifest with all the information about a distribution and the components bundled in that distribution.

[dblock]

I opened opensearch-project/opensearch-build#5130 to see what the infra team says about this (cc: @gaiksaya).
@gaiksaya

Will add more details to the issue but docker image is build using tarball. And all the distributions contains distribution manifest with all the information about a distribution and the components bundled in that distribution.

It's just hard to tell from a distribution what the docker SHA is.

[SwethaGuptha]

@dblock Any inputs on the next steps to make progress on this PR?

[dblock]

@SwethaGuptha yes, update the SHAs to the latest available for 2.18 and 3.0 and see if all tests pass - it has to pass 2.18, but you can mark tests as < 3.0 if that one doesn't pass, for now

[dblock]

Now that 2.18 has been released this should be easier.

[github-actions]

Spec Test Coverage Analysis

Total	Tested
517	349 (67.5 %)

[SwethaGuptha]

@dblock Can you please help with the review?

[dblock]

Looks good, some cosmetic asks, please.

[dblock]

Sorry to be annoying, some more small stuff flagged here.

[dblock]

Thanks for taking this on, merged!

There's also node stats, do those have to mirror cluster stats?

 GET /_nodes/{node_id}/stats/{metric}/{index_metric}
 GET /_nodes/{node_id}/usage
 GET /_nodes/{node_id}/usage/{metric}
 GET /_nodes/{node_id}/{metric}

[nhtruong]

@dblock
So cluster.stats will have the following paths:

• /_cluster/stats
• /_cluster/stats/nodes/{node_id}
• /_cluster/stats/{metric}/nodes/{node_id}
• /_cluster/stats/{metric}/{index_metric}/nodes/{node_id}

current path-finding strat for the JS CodeGen will create:

  const path = ['/_cluster/stats/', metric, '/', index_metric, '/nodes/', node_id].filter(c => c).join('').replace('//', '/');

which works fine for most situations EXCEPT for when no path params are provided since it will yield /_cluster/stats/nodes, which is not a valid path. I've gotta update the CodeGen for JS (I really like the above solution if not for this edge case 😢 )
cc: @Xtansia in case this affects Java/.NET CodeGen too.

[dblock]

@nhtruong I think these are 2 separate APIs, one is cluster stats (/_cluster/stats), and the other is cluster/nodes stats (the other 3), would that help?

[nhtruong]

I'm referring to these 4 operations: https://github.com/opensearch-project/opensearch-api-specification/pull/639/files#diff-c68dc8d4bd22aabd667fe0978fba9a121988d77ac766b1e2a5e94091603c0734R305-R366

It's no big deal. We just can't have that one-line solution 🥲

[dblock]

@nhtruong Yes, I think they should be totally different operations, no? would that not work?

[nhtruong]

They are in the same operation-group which means they will be piped into the same API function on the client. That function has to pick a path depending on the path params provided by the user. NodeJS CodeGen is using that one-line solution which works for the vast majority of the operation groups, even the notorious nodes.info:

• /_nodes
• /_nodes/{node_id}
• /_nodes/{metric}
• /_nodes/{node_id}/{metric}

const path = ['/_nodes/', node_id, '/', metric].filter(c => c).join('').replace('//', '/');

It's not hard to switch up the path selection logic to account for this edge case.

[dblock]

They are in the same operation-group

Is this correct?

[nhtruong]

Yes, the 4 operations I stated in #639 (comment) are in cluster.stats