Microservices & Ports

Overview of the 4 core microservices and supporting infrastructure components.

Go 1.24

Port: 8080 (HTTP)

Role: Entry point for external traffic. Handles JWT verification, rate limiting, and request routing.

Dependencies: Payment Service, Account Service, SPIRE Agent, Jaeger.

Go 1.24

Port: 8081 (gRPC)

Role: Orchestrates payment flow. Validates requests, ensures idempotency, and publishes events.

Dependencies: Account Service, Kafka, PostgreSQL, Redis, SPIRE Agent.

Go 1.24

Port: 50051 (gRPC)

Role: Manages user balances. Handles transactional updates and read-heavy operations.

Dependencies: PostgreSQL, Redis, Kafka Consumer, SPIRE Agent.

Java 21 / Spring Boot

Port: 8083 (HTTP)

Role: Consumes payment events and sends notifications (mocked logging).

Dependencies: Kafka Consumer, Jaeger.

Infrastructure Components

Component	Type	Port	Function
PostgreSQL	Database	5432	Primary data store (Payments & Accounts schemas).
Apache Kafka	Message Broker	9092	Asynchronous event bus for decouping services.
Redis	Cache	6379	Idempotency keys and balance caching.
SPIRE Server	Identity Provider	8081	Issues SVIDs for mTLS authentication.
Jaeger	Observability	16686 (UI) / 4317 (OTLP)	Distributed tracing visualization.