A Kafka-based microservices project implementing a distributed Order Processing System, comprised of three independent services: Order, Inventory, and Payment. These services communicate asynchronously using Kafka topics to ensure loose coupling and high scalability.
- Accepts customer orders.
- Publishes events to Kafka.
- Listens for payment status updates.
- Listens for new order events.
- Checks and reserves inventory.
- Publishes success or failure events.
- Listens for reserved inventory events.
- Simulates/generates payment.
- Updates payment status.
Each service has its own isolated PostgreSQL database instance for data encapsulation and autonomy (following the Database per Service pattern).
| Kafka Topic | Description | Publisher | Subscriber(s) |
|---|---|---|---|
order.created.v1 |
Published when a new order is created. | Order Service | Inventory Service |
inventory.reserved.v1 |
Published after inventory is successfully reserved. | Inventory Service | Payment Service |
inventory.failed.v1 |
Published if inventory reservation fails. | Inventory Service | Order Service |
payment.generated.v1 |
Published when payment is generated/simulated. | Payment Service | Order Service |
order.payment.updated.v1 |
Published to notify order status update after payment. | Order Service | (For downstream services, if any) |