Event Grid Publish-Subscribe Architecture

Azure Event Grid uses topics and event subscriptions to build event-based solutions that react to changes in Azure services or custom applications. A topic is an endpoint where events are published, and an event subscription tells Event Grid which events to deliver and where to send them. Event handlers process delivered events, which can be webhooks, Azure Functions, Logic Apps, or other Azure services. By using Event Grid, you achieve loosely coupled event routing and high scalability.

When creating topics, you can choose from:

• Custom topics for your own applications, supporting CloudEvents or Event Grid schema and push delivery.
• System topics generated by Azure services (like Storage or Service Bus), created implicitly when you subscribe.
• Namespace topics for MQTT routing, using a simplified filtering model.
• Partner topics for SaaS or ERP integrations via Partner Events.