Upgrade to Spring Boot 3.4.10 and Spring Cloud 2024.0.0

[devin-ai-integration]

Upgrade to Spring Boot 3.4.10 and Spring Cloud 2024.0.0

Summary

Comprehensive upgrade of all 7 microservices from Spring Boot 2.7.x to 3.4.10 and Spring Cloud 2021.0.8 to 2024.0.0. This addresses the end-of-life status of Spring Boot 2.7.x (EOL November 2023) and migrates to actively supported versions.

Key Changes:

• POM Updates: All 7 services upgraded to Spring Boot 3.4.10 and Spring Cloud 2024.0.0
• Jakarta EE Migration: Migrated all entity classes from javax.persistence.* to jakarta.persistence.* (6 entity files)
• Transaction API Migration: Updated javax.transaction.Transactional to jakarta.transaction.Transactional in UserServiceImpl
• Spring Security 6.x: Modernized API-Gateway SecurityConfig from deprecated .and() chaining to lambda DSL pattern
• Spring Framework 6.x: Updated GlobalExceptionHandler classes to use HttpStatusCode instead of HttpStatus in method signatures (User-Service, Account-Service, Fund-Transfer)
• Spring Cloud 2022.0.x+: Removed deprecated @EnableEurekaClient annotations (now auto-configured)

Services Affected:

• Service-Registry (Eureka Server)
• API-Gateway (Spring Cloud Gateway + OAuth2)
• User-Service (JPA + Keycloak)
• Account-Service (JPA + Feign)
• Fund-Transfer (JPA + Feign)
• Transaction-Service (JPA + Feign)
• Sequence-Generator (JPA)

Verification Performed:
✅ All 7 services compile successfully
✅ Tests pass for Service-Registry, Sequence-Generator, and API-Gateway
✅ No remaining javax.* imports detected

Review & Testing Checklist for Human

⚠️ CRITICAL - The following require manual verification with full infrastructure:

• Start all external dependencies (MySQL database + Keycloak authentication server) and verify all 4 database-dependent services (User-Service, Account-Service, Fund-Transfer, Transaction-Service) start successfully without errors
• Test OAuth2/Keycloak authentication flows through API-Gateway: user registration, login, token refresh, and accessing protected endpoints - the Spring Security 6.x lambda DSL changes need real-world validation
• Verify Eureka service discovery: Confirm all services register with Service-Registry correctly after removing @EnableEurekaClient annotations (should be auto-configured in Spring Cloud 2022.0.x+)
• Test database CRUD operations on all entity classes to ensure Jakarta persistence annotations work correctly with MySQL
• Verify inter-service communication via Feign clients (e.g., Account-Service → User-Service, Fund-Transfer → Account-Service, Transaction-Service → Account-Service)

Notes

• Version Selection: Chose Spring Boot 3.4.10 (OSS support until December 2025) over 3.2.x (EOL December 2024) and 3.5.x (newer but less mature)
• Testing Limitation: Only 3 services have automated tests that could run without external dependencies. Runtime behavior of the 4 database-dependent services needs manual verification
• Breaking Changes Addressed:
  • Jakarta EE namespace migration (javax → jakarta)
  • Spring Security 6.x deprecations (.authorizeExchange() → lambda DSL)
  • Spring Framework 6.x ResponseEntityExceptionHandler signature changes
  • Spring Cloud 2022.0.x+ Eureka client auto-configuration
• Keycloak Compatibility: Keycloak Admin Client 21.0.1 (in User-Service) is compatible with Spring Boot 3.4.10
• Java Version: Already using Java 17 (required for Spring Boot 3.x)

Link to Devin run: https://app.devin.ai/sessions/385cd2f3afe540568ac6a851d0f391fe
Requested by: @samfert-codeium

[devin-ai-integration]

🤖 Devin AI Engineer

I'll be helping with this pull request! Here's what you should know:

✅ I will automatically:

• Address comments on this PR. Add '(aside)' to your comment to have me ignore it.
• Look at CI failures and help fix them

Note: I can only respond to comments from users who have write access to this repository.

⚙️ Control Options:

• Disable automatic comment and CI monitoring