Add missing tests for ML APIs (search and delete)

[nathaliellenaa]

Description

Added missing tests for GET /_plugins/_ml/models/_search and DELETE /_plugins/_ml/tasks/{task_id}.

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[github-actions]

Changes Analysis

Commit SHA: c7569ac
Comparing To SHA: 398481e

API Changes

Summary

└─┬Components
  ├──[➕] schemas (52227:7)
  ├──[➕] schemas (52079:7)
  ├─┬ml._common___HitsTotal
  │ └─┬value
  │   └──[➕] format (52058:19)❌ 
  ├─┬ml._common___SearchModelsResponse
  │ ├──[➕] properties (52220:9)
  │ ├──[➕] properties (52217:9)
  │ └──[➕] properties (52214:9)
  ├─┬ml._common___SearchModelsHitsHit
  │ ├──[➕] required (52198:11)❌ 
  │ ├──[➖] required (52167:11)❌ 
  │ ├──[➖] required (52168:11)❌ 
  │ ├──[➕] properties (52182:9)
  │ ├──[➕] properties (52189:9)
  │ ├──[➕] properties (52180:9)
  │ ├──[➕] properties (52193:9)
  │ ├──[➕] properties (52178:9)
  │ ├─┬model_id
  │ │ └──[🔀] $ref (32155:13)❌ 
  │ ├─┬_id
  │ │ └──[🔀] $ref (31892:13)❌ 
  │ └─┬_index
  │   └──[🔀] $ref (31949:13)❌ 
  └─┬ml._common___SearchModelsHits
    └──[➕] properties (52168:9)

Document Element	Total Changes	Breaking Changes
components	18	7

• ❌ BREAKING Changes: 7 out of 18
• Modifications: 3
• Removals: 2
• Additions: 13
• Breaking Removals: 2
• Breaking Modifications: 3
• Breaking Additions: 2

Report

The full API changes report is available at: https://github.com/opensearch-project/opensearch-api-specification/actions/runs/11865305204/artifacts/2196583379

API Coverage

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

[dblock]

Looks good, needs a bit of work, iterate to green.

1. Fix validation/CI failures.
2. Sign DCO, git commit --amend -s for existing commits.

[dblock]

The types for many of these things are too broad, I noted some below, but do look for existing fields with the same name for everything and see how they are declared with a ref.

Update CHANGELOG.

[dblock]

The test failure looks legit, probably needs a refresh or maybe something more.

ERROR   ml/models.yaml (tests/plugins/ml/ml/models.yaml)
    ERROR   CHAPTERS
        PASSED  Register model.
            PASSED  REQUEST BODY
            PASSED  RESPONSE STATUS
            PASSED  RESPONSE PAYLOAD BODY
            PASSED  RESPONSE PAYLOAD SCHEMA
            PASSED  RESPONSE OUTPUT VALUES
        ERROR   Search model.
            PASSED  REQUEST BODY
            PASSED  RESPONSE STATUS
            FAILED  RESPONSE PAYLOAD BODY (missing hits.hits[0]='[object Object]')
            PASSED  RESPONSE PAYLOAD SCHEMA
            ERROR   RESPONSE OUTPUT VALUES (Expected to find non undefined value at `payload.hits.hits[0]._id`.)
        SKIPPED Wait to get completed task.
        SKIPPED Delete model.

[dblock]

Some tests are still failing.

[dblock]

Getting there!

[dblock]

            FAILED  RESPONSE PAYLOAD SCHEMA (data/hits/hits/27/_source/model_content_hash_value property is not defined in the spec, data/hits/hits/27/_source/last_registered_time property is not defined in the spec, data/hits/hits/27/_source/model_content_size_in_bytes property is not defined in the, ...)

Looks like more fields are missing, https://github.com/opensearch-project/ml-commons/blob/9c1b8a8c1e28ab8bdaf507cb71799c4809c3d8c6/plugin/src/test/resources/org/opensearch/ml/autoredeploy/ModelResult.json#L7.

[github-actions]

Spec Test Coverage Analysis

Total	Tested
517	351 (67.89 %)

[dblock]

Passing tests!