Instagram Integration (Core APIs) Overview Your task is to implement three common, reusable REST APIs that handle Instagram account linking, data fetching, and token lifecycle management using official Meta app. What You Have to Build (Only 3 APIs) Link Instagram Account API Goal Allow a user to link their Instagram account using the official OAuth flow and store a user-scoped access token. What to implement Start Instagram OAuth authorization flow Handle OAuth callback securely Exchange authorization code for access token Store token in DB with: Access token Expiry Granted scopes Instagram account type (personal / business / creator) Single-step consent (login + permissions together) Supported account types Personal (public / private) Business Creator Endpoints GET /api/v1/instagram/link GET /api/v1/instagram/callback Expected result Instagram account is linked User-scoped token is saved securely Account metadata is stored Instagram Data Fetch API Goal Fetch Instagram data using the stored user token and persist it in the database. What to implement Use stored access token to call official Instagram APIs Fetch (only what is allowed by account type & scopes): User profile details Recent posts/media Followers list (only if API allows) Handle pagination properly Map responses into: DTOs JPA entities Persist data using Spring Data JPA Gracefully handle missing/restricted fields Endpoint POST /api/v1/instagram/fetch Expected result Data stored in DB Clean, structured response returned Refresh / Unlink Instagram Account API Goal Manage token lifecycle and allow account unlinking. What to implement Refresh access token (if supported) Detect expired/invalid tokens Revoke Instagram access when user unlinks Cleanup: Stored tokens Related Instagram data (if required) Endpoints POST /api/v1/instagram/refresh DELETE /api/v1/instagram/unlink Expected result Tokens refreshed or revoked correctly Account cleanly unlinked Technical Requirements Spring Boot (latest stable) Spring Security (OAuth handling) Spring Data JPA Any SQL DB (Postgres) Clean architecture: Controller Service Instagram API client DTOs & Entities Centralized error handling Basic unit tests for: OAuth flow Token storage Fetch logic Deliverables Working Spring Boot project Runs locally with: mvn spring-boot:run README containing: Environment variables Instagram OAuth setup steps Endpoint details Postman collection or cURL scripts showing: Link → Authorize → Fetch → Refresh/Unlink flow Why Only These 3 APIs (For Clarity) These APIs form the core Instagram integration layer. Everything else depends on: Account identity User-scoped authorization Reliable data ingestion Once this is done: No OAuth duplication later No re-authorization issues Fully policy-compliant Easy to extend with new features Compliance Expectations Use official Meta / Instagram APIs only Use user-scoped access tokens No scraping, no private endpoints Support token revocation Respect data access limits per account type Meta App Setup (Important) A live setup call is required where you will: Guide us in creating the Meta App Configure: App type Instagram product OAuth redirect URLs Required scopes Verify test login & permissions Ensure the app is policy-compliant This setup is part of the task. Acceptance Criteria OAuth works end-to-end Tokens are user-scoped and stored securely APIs work for all Instagram account types (with correct limitations) Code is clean, extensible, and production-ready Project runs locally without errors Swagger Page to test these 3 api