Added FlatObjectProperty.

[dblock]

Description

• We already have index mapping tests in https://github.com/opensearch-project/opensearch-api-specification/blob/main/tests/default/indices/mapping.yaml, so no need to duplicate them under core.
• Added FlatObjectProperty index mapping returned in .opensearch-observability.
• Added a test to get mappings for all indices, seems to not run into [BUG] Spec testing for GET /_mapping runs out of memory #384 anymore.

Issues Resolved

Closes #384.

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[github-actions]

Changes Analysis

Commit SHA: 84bab06
Comparing To SHA: 62f1f5f

API Changes

Summary

└─┬Components
  ├──[➕] schemas (39154:7)
  └─┬_common.mapping___Property
    ├──[➕] oneOf (39120:7)
    ├─┬ONEOF
    │ └──[🔀] $ref (39155:9)❌ 
    ├─┬ONEOF
    │ └──[🔀] $ref (39995:9)❌ 
    ├─┬ONEOF
    │ └──[🔀] $ref (39200:9)❌ 
    ├─┬ONEOF
    │ └──[🔀] $ref (39045:9)❌ 
    ├─┬ONEOF
    │ └──[🔀] $ref (39214:9)❌ 
    ├─┬ONEOF
    │ └──[🔀] $ref (39812:9)❌ 
    ├─┬ONEOF
    │ └──[🔀] $ref (38967:9)❌ 
    ├─┬ONEOF
    │ └──[🔀] $ref (38879:9)❌ 
    ├─┬ONEOF
    │ └──[🔀] $ref (38991:9)❌ 
    ├─┬ONEOF
    │ └──[🔀] $ref (39413:9)❌ 
    ├─┬ONEOF
    │ └──[🔀] $ref (39548:9)❌ 
    ├─┬ONEOF
    │ └──[🔀] $ref (40025:24)❌ 
    ├─┬ONEOF
    │ └──[🔀] $ref (39484:9)❌ 
    └─┬ONEOF
      └──[🔀] $ref (39984:9)❌ 

Document Element	Total Changes	Breaking Changes
components	16	14

• ❌ BREAKING Changes: 14 out of 16
• Modifications: 14
• Additions: 2
• Breaking Modifications: 14

Report

The full API changes report is available at: https://github.com/opensearch-project/opensearch-api-specification/actions/runs/11779944286/artifacts/2171498248

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	40	0

[github-actions]

Spec Test Coverage Analysis

Total	Tested
515	319 (61.94 %)