feat(healthendpoint): Refactor health endpoint in all services to run on same port as main service

bonzofenix commented 3 months ago

Overview

MTLS verification is performed server-side for communication in between App Autoscaler components. To prepare components to run as Cloud Foundry (CF) apps on SAP BTP, we need to merge the health and service ports for each service, as there is no [TCP routing]() enabled. The /health endpoints in each CF Autoscaler component are monitored by our Cloud Engineering Team and must remain available without MTLS requirements. When migrating apps from BOSH VMs to CF, apps can only listen on a single port in the container. Therefore, the health endpoint and / health metrics must be available on the same service of the server.

Whats new

• Basic Authentication Implementation: Introduced basic authentication for multiple components, including scaling engine, event generator, and operator. • OpenAPI Specification Enhancements: Added new API endpoints for scaling history and improved existing API structures. • Prometheus Integration: Enhanced health monitoring with Prometheus metrics collection for various services. • Refactoring and Code Cleanup: Streamlined code by removing unused dependencies and consolidating authentication logic. • Testing Improvements: Expanded test coverage for new authentication mechanisms and API endpoints. • Configuration Management: Updated configuration files to reflect new authentication parameters and removed deprecated settings.

Why should we merge this PR in one go

Component communication using basic auth would be enabled and running before migrating to CF.
No duplication of unit test would be needed supporting mtls+multiple server ports vs Basicauth+single server port

Why we would not want to merge this PR

Any consumer relaying on mtls would need to relay on basic auth from now own (MTLS would be deprecated)
No rollback option in case of unknown issues (relaying on existing acceptance+performance+integration tests)