[Feature/extensions] Get Extension API during initialization

[dbwiddis]

Signed-off-by: Daniel Widdis [email protected]

Description

(This is a draft PR submitted for review/feedback of initial approach. Please wait until all sub-issues are complete before merging.)

Companion PR: opensearch-project/opensearch-sdk-java#71

Extensions will report their APIs to the ExtensionsOrchestrator during initialization. These APIs will be registered and mapped so that when Users submit API requests they can be forwarded to the appropriate extensions.

Issues Resolved

Meta issue opensearch-project/opensearch-sdk-java#64

• [FEATURE] Send required REST APIs to OpenSearch opensearch-sdk-java#68
• [FEATURE] Register REST API and map to associated extension in ExtensionsOrchestrator opensearch-sdk-java#69
• [FEATURE] Redirect REST API request to appropriate extensions opensearch-sdk-java#70

Check List

• New functionality includes testing.
  • All tests pass
• New functionality has been documented.
  • New functionality has javadoc added
• Commits are signed per the DCO using --signoff

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[github-actions]

Gradle Check (Jenkins) Run Completed with:

• RESULT: FAILURE ❌
• URL: https://build.ci.opensearch.org/job/gradle-check/1148/
• CommitID: 2ce1dcd

[dbwiddis]

Based on feedback regarding future flexibility as mentioned in #68, closing this. Will start over with a different approach.