ordergo

Event-driven order system using Saga Choreography (Kafka + Go). The repo contains four services and shared contracts/libraries. Services communicate via Kafka and maintain their own databases.

Services

• ordersvc: accepts orders, persists, emits order.created, updates status
• inventorysvc: reserves stock, emits inventory.reserved or inventory.failed
• paymentsvc: processes payment, emits payment.completed or payment.failed
• notificationsvc: stores notifications, emits notification.sent

Event flow

order.created -> inventory.reserved | inventory.failed inventory.reserved -> payment.completed | payment.failed payment.* -> notification.sent inventory.failed -> order.cancelled

Requirements

• Docker + Docker Compose
• Go 1.22 (only needed if you run services on host)

Quick start (Docker)

1. Start Kafka + databases + AKHQ UI

make infra-up

2. Create Kafka topics

make kafka-topics

3. Build and run services

make services-up

4. Open AKHQ

• http://localhost:8088

Ports

• ordersvc HTTP: 8080
• AKHQ UI: 8088
• Kafka host listener: 9094
• orders-db: 5433
• inventory-db: 5434
• payments-db: 5435
• notifications-db: 5436

HTTP API (ordersvc)

Create order

curl -X POST http://localhost:8080/orders \
  -H 'Content-Type: application/json' \
  -d '{
    "customer_id": "C123",
    "items": [{"sku":"SKU-1","qty":2,"price":10000}],
    "total_amount": 20000
  }'

Kafka topics

• order.created
• order.cancelled
• inventory.reserved
• inventory.failed
• payment.completed
• payment.failed
• notification.sent

Config files

• Host mode: */config/config.yaml (Kafka broker localhost:9094)
• Docker mode: */config/docker.yaml (Kafka broker kafka:9092)

Make targets (selected)

• make infra-up / make infra-down
• make kafka-topics
• make services-up / make services-down
• make services-logs
• make akhq-logs

Runbook

See docs/runbook.md for step-by-step scenarios and event expectations.

Notes

• Inventory seed data lives in scripts/seed/inventory.sql.
• Idempotency is handled with a processed_messages table per service.