OrderFlow

A small .NET 10 project for practicing asynchronous order processing, RabbitMQ messaging, and safe message redelivery.

How it works

1. POST /api/orders saves an order with the Pending status and publishes OrderCreated through the transactional outbox.
2. The inventory consumer reserves stock and publishes either InventoryReserved or InventoryReservationFailed.
3. A successful reservation starts a simulated payment. PaymentCompleted changes the order status to Confirmed.
4. A failed reservation changes the order status to Cancelled.

Order reads use Redis with the cache-aside pattern. Inventory reservations are idempotent per OrderId.

Stack

• .NET 10 / ASP.NET Core
• EF Core / PostgreSQL
• MassTransit / RabbitMQ
• Redis
• xUnit / NSubstitute
• Docker Compose

Running with Docker

Requirements: Docker.

docker compose up --build

This starts PostgreSQL, Redis, RabbitMQ and the API. The API waits for the dependencies to become healthy and applies EF Core migrations on startup.

• Swagger: http://localhost:5173/swagger
• Liveness: http://localhost:5173/health/live
• Readiness: http://localhost:5173/health/ready
• RabbitMQ Management: http://localhost:15672 (guest / guest)

Database data lives in the named postgres_data volume and survives docker compose down. Use docker compose down -v to remove that volume and drop the database.

Running from the SDK

Requirements: .NET 10 SDK and Docker.

docker compose up -d postgres redis rabbitmq
dotnet run --project src/OrderFlow.Api --launch-profile http

Example request:

POST http://localhost:5173/api/orders
Content-Type: application/json

{
  "items": [
    {
      "productId": "11111111-1111-1111-1111-111111111111",
      "quantity": 1
    }
  ]
}

Tests

dotnet test OrderFlow.sln