bmb.production

This project, bmb.production, is the production/kds microservice for a fast food application. It provides a simple API that allows users to see which orders need to be prepared and update its statuses and they move through the manufacturing pipeline. Additionally, it integrates with other domain microservices through messaging using MassTransit.

Database

The terraform modules create a redis instance as part of the infrastructure. The decision to go with redis is based on the usage of this particular microservice. It will have a higher load of requests and the responses needs to be the closest to realtime, so users can see their orders status updates.

Masstransit

It uses Masstransit to manage communication between services. Masstransit automatically creates Topics, Queues and Subscriptions.

Event Subscriptions

OrderCreated Event

• Subscribes to OrderCreated events.
• Adds the order to the orders list using the order ID as the key.

OrderPaymentConfirmed Event

• Subscribes to OrderPaymentConfirmed events.
• If the orders list contains the received OrderId:
  • Adds TrackingCode:OrderId to the Received queue.

Queues

• Received: Queue for orders that have been received.
• InPreparation: Queue for orders that are currently being prepared.
• Ready: Queue for orders that are ready for pickup or delivery.

Endpoints

List Orders

• Endpoint: Lists all orders.
• Response Object:

{
  "received": [
    {
      "orderId": "b39c3d69-2e43-47df-8b86-0037975ae211",
      "code": "ASD-12"
    }
  ],
  "inPreparation":[
    {
      "orderId": "b33c3d69-2e43-47df-8b86-0037975ae211",
      "code": "ASD-12"
    }
  ],
  "ready": [
    {
      "orderId": "c39c3d69-2e43-47df-8b86-0037975ae211",
      "code": "ASD-22"
    }
  ],
}

Update Order Status

• Endpoint: Updates the status of an order.
• Request Parameters:
  • trackingCode: The tracking code of the order.
  • status: The new status of the order. Valid statuses are InPreparation, Ready, or Completed.
• Status Change Rules:
  • Status transitions must follow the sequence: Received -> InPreparation -> Ready -> Completed.
  • Status changes cannot be rolled back.
  • If the order status is Completed, it should be removed from the orders list.
• Events:
  • An OrderStatusChanged event should be triggered on every status change operation.

Use Cases

ReceiveOrderUseCase

• Trigger: Executed from the OrderPaymentConfirmed event.
• Actions:
  • Adds the order to the Received queue.
  • Publishes an OrderStatusChanged event with the status value Received.

PrepareOrderUseCase

• Trigger: Executed when an order needs to be prepared.
• Actions:
  • Removes the order from the Received queue.
  • Adds the order to the InPreparation queue.
  • Publishes an OrderStatusChanged event with the status value InPreparation.

FinishOrderPreparationUseCase

• Trigger: Executed when an order preparation is finished.
• Actions:
  • Removes the order from the InPreparation queue.
  • Adds the order to the Ready queue.
  • Publishes an OrderStatusChanged event with the status value Ready.

CompleteOrderUseCase

• Trigger: Executed when an order is completed.
• Actions:
  • Removes the order from the Ready queue.
  • Removes the order from the list.
  • Publishes an OrderStatusChanged event with the status value Completed.

This repo on the infrastructure

K8S