Azure Event Grid: Overview and Key Concepts

Introduction

Welcome to the lecture on Azure Event Grid. In this session, we'll cover:

• What Azure Event Grid is.
• Why it should be used.
• Key features and concepts of Azure Event Grid.

Future sessions will include hands-on demonstrations using the Azure Portal.

What is Azure Event Grid?

• Centralized service in Azure for routing events.
• Based on a publish and subscribe model:
  • Publish: Events are sent to the Event Grid.
  • Subscribe: Actions or handlers subscribe to these events.

Key Components

Publishers

• Sources of events in Azure.
• Examples: Azure Blob Storage (file creation), Virtual Machine creation, etc.

Event Handlers

• Actions triggered by events.
• Examples: Logic App, Azure Functions, Event Hub, Webhooks.
• Only handlers subscribed to an event will execute.

Topics

• HTTP endpoint where events are sent.
• Types:
  • System Topics: Built-in topics.
  • Custom Topics: User-created topics.

Subscriptions

• Bridge between Event Handlers and Event Grid.
• Allows specific handlers to react to events.

One-to-Many Relationship

• A single event can have multiple subscriptions.

Use Cases

• Notifying users about file uploads in a music sharing application.
• Sending emails in response to various events.

Advanced Features

• Advanced Filtering: Subscribers can filter which topics to subscribe to.
• Fan-Out: A single event can be delivered to multiple subscribers.
• Reliability: Event Grid retries up to 24 hours if delivery fails.
• Pay per Event: Charged for each message/event.
• High Throughput: Can process millions of events per second.

Azure Subscriptions

• Azure itself can act as an event source.
  • Example: Notifications for resource creation or deletion.

Basic Concepts Summary

• Events: What happened (e.g. file upload in Blob Storage).
• Event Source/Publisher: Where it happened (e.g. Blob Storage).
• Topics: HTTP endpoint for events.
  • System Topics: Built-in.
  • Custom Topics: User-defined.
• Event Handlers (Subscribers): Who handles it (e.g. Logic Apps, Functions).
• Subscriptions: Bridge connecting event to the handler.

Conclusion

• Azure Event Grid is a powerful tool for building event-based or serverless applications in Azure.
• Simple yet highly effective with capabilities like advanced filtering, fan-out, reliability, and cost-effectiveness.
• Upcoming sessions will include practical demonstrations.

Thank you for attending this session.