You are building a serverless AI workflow that triggers an Azure Function whenever a new file is uploaded to an Azure Blob Storage container. The Function must start processing within seconds of the upload and should not require polling. Which Azure service should you use to connect Blob Storage to the Function?
Azure Event Grid is a fully managed event routing service that can subscribe to Blob Storage events such as BlobCreated. When a file is uploaded, Event Grid pushes the event to the Function endpoint, providing near real-time, push-based delivery without polling. This is the recommended approach for reactive serverless workflows triggered by Blob Storage changes.
Why this answer
Azure Event Grid natively integrates with Blob Storage to publish events like BlobCreated, and it can push these events directly to an Azure Function. This provides a serverless, push-based trigger that processes files within seconds without polling, making it the correct choice for the scenario.
Exam trap
The trap here is assuming that any messaging service can trigger a Function on Blob Storage upload, when only Event Grid provides native, push-based eventing from Blob Storage.