Spring Cloud Case Studies & Practical Application 2

Question 1

A retail company notices that their order service frequently fails when the inventory service is slow. Which Spring Cloud pattern should they implement first to prevent cascading failures?

Accepted Answer

Resilience4j Circuit Breaker on the order service

Answer

A Circuit Breaker on the calling service (order) opens after repeated failures, preventing cascading overload to the already-slow inventory service.

Question 2

An e-commerce platform uses Spring Cloud Config Server backed by Git. A developer pushes a bad property that crashes all payment microservices. What is the fastest recovery approach?

Accepted Answer

Revert the Git commit and call /actuator/refresh on each service

Answer

Reverting the Git commit fixes the source and calling /actuator/refresh (or /actuator/bus-refresh with Spring Cloud Bus) propagates the corrected config without redeployment.

Question 3

A startup runs 5 microservices locally for development. Developers are frustrated by manually updating hostnames in each service's application.yml. What Spring Cloud solution eliminates this?

Accepted Answer

Spring Cloud Netflix Eureka service discovery

Answer

Eureka allows services to register themselves and discover peers by logical name, eliminating hard-coded hostnames in configuration.

Question 4

A financial firm needs all inter-service HTTP calls logged with a shared trace ID for audit purposes. Which Spring Cloud component provides this out of the box?

Accepted Answer

Spring Cloud Sleuth (Micrometer Tracing)

Answer

Spring Cloud Sleuth (now Micrometer Tracing) automatically instruments HTTP calls with trace and span IDs that propagate across service boundaries.

Question 5

A team uses OpenFeign to call a product service. During load testing, they see thread pool exhaustion. Which Resilience4j integration change best addresses this?

Accepted Answer

Switch from BulkheadType.THREADPOOL to BulkheadType.SEMAPHORE

Answer

Semaphore bulkheads limit concurrent calls without spawning extra threads, preventing thread pool exhaustion while still controlling concurrency.

Spring Cloud Practice Test

Spring Cloud Practice Test

Spring Cloud Case Studies & Practical Application 2