AZ-204 Case Studies & Practical Application 3

Question 1

A company's Azure Function uses a Storage Queue trigger. During a traffic spike, 50,000 messages arrive and the function scales out. Developers notice duplicate message processing. What is causing this and how should it be addressed?

Accepted Answer

Queue Storage guarantees at-least-once delivery; use idempotent logic or track processed message IDs

Answer

Azure Storage Queues guarantee at-least-once delivery, so duplicates are expected; the correct pattern is idempotent processing rather than relying on the queue for deduplication.

Question 2

A developer needs to implement a background job in an Azure Web App that runs every 15 minutes. The job must co-locate with the web app and share its environment variables. What is the simplest approach?

Accepted Answer

Add a triggered WebJob with a CRON schedule set to '0 */15 * * * *'

Answer

WebJobs run within the same App Service plan and share the app's settings, making them the simplest co-located scheduling option without provisioning additional resources.

Question 3

An application writes telemetry to Application Insights. In production, the volume is very high and costs are excessive. The developer wants to reduce data volume but retain all exceptions and slow requests. Which strategy should be applied?

Accepted Answer

Configure adaptive sampling with a rule to exclude exceptions and dependency failures from sampling

Answer

Adaptive sampling intelligently reduces volume while allowing exclusion of critical telemetry types like exceptions, preserving diagnostic fidelity at lower cost.

Question 4

A developer is building an API secured by Azure AD. A client app must call the API on behalf of a signed-in user. Which OAuth 2.0 flow should be used?

Accepted Answer

Authorization Code flow with PKCE

Answer

Authorization Code flow with PKCE is the recommended flow for user-delegated access from a client app, providing both security and user context to the API.

Question 5

A retail app stores session state in Azure Cache for Redis. After a Redis failover, users are logged out. The developer wants sessions to survive failover. What should be configured?

Accepted Answer

Enable Redis persistence (AOF or RDB) on a Premium tier cache

Answer

Redis persistence (AOF or RDB snapshots) on the Premium tier saves data to disk so sessions survive failover events.

AZ-204 - Microsoft Azure Developer Associate Practice Test

AZ-204 - Microsoft Azure Developer Associate Practice Test

AZ-204 Case Studies & Practical Application 3