Question

A retail company is redesigning its order-processing platform on Azure. When a customer places an order, a single event must reliably trigger multiple independent downstream systems: an inventory service, a shipping service, and an analytics pipeline. Each subscriber processes messages at its own pace, and no subscriber should lose messages if it is temporarily offline. The publisher must not know or be coupled to the number of subscribers. Which messaging design should the architect recommend?

Accepted Answer

Publish order events to Azure Event Grid, with each downstream system subscribing via its own Azure Service Bus queue as the event handler

Answer

Have the order service write directly to a single Azure Storage queue that all three downstream systems poll competitively

Answer

Send order events to a single Azure Service Bus queue and let the three services read from it in a round-robin pattern

Answer

Invoke each downstream system synchronously through Azure API Management using HTTP calls from the order service