An iris-swale app must run a Function when a blob is created, not every minute on a schedule. Which service best delivers that discrete reactive event?
Select an answer to reveal the explanation.
Short Explanation
When something happens, push the fact—don’t poll on a timer. Event Grid is built for discrete reactive events like a blob appearing.
Full Explanation
When an iris-swale app must run a Function because a blob was created—not because a clock ticked—Event Grid is the service that delivers that discrete reactive event. Storage can emit BlobCreated-style events through an Event Grid system topic to a Function, webhook, or other handler as soon as the create happens.
A timer trigger that lists the container every sixty seconds forever fails the reactive model: it adds latency up to the poll interval, burns invocations when nothing changed, and is not event delivery.
Application Insights live metrics streamed as a substitute for events fails because telemetry observability is not a BlobCreated event fabric for triggering business handlers.
Azure Cache for Redis pub/sub as the “required Domain 5 event bus” fails this scenario: Redis pub/sub is not the Azure Event Grid path for first-party storage blob create notifications the exam emphasizes here.
Exam caveat: Event Grid suits discrete reactions; high-volume continuous telemetry belongs on Event Hubs—do not force every sensor sample through Event Grid. Operational check: upload a test blob, confirm the system topic subscription fires the Function once per create, and compare with a timer path to show the evented handler does not need perpetual listing.