Spring Cloud Research & Evidence-Based Practice 5

Question 1

When adopting Spring Cloud Kubernetes ConfigMap-based configuration, evidence-based practice recommends enabling which feature to refresh beans without a pod restart?

Accepted Answer

Enabling spring.cloud.kubernetes.config.reload.enabled=true to hot-reload properties on ConfigMap change

Answer

The reload feature watches the Kubernetes API for ConfigMap changes and triggers a context refresh, enabling dynamic configuration without a pod restart.

Question 2

A research survey of Spring Cloud teams found that which observability gap most frequently delays mean time to resolution (MTTR) during incidents?

Accepted Answer

Missing correlation between distributed traces and application logs, making it impossible to isolate log lines for a failing request

Answer

Without trace ID injection into logs, engineers cannot filter logs to a single request trace, forcing time-consuming manual log triage during incidents.

Question 3

Evidence from production Spring Cloud deployments shows that when using Resilience4j Semaphore BulkHead, which misconfiguration most commonly causes thread starvation?

Accepted Answer

Setting maxConcurrentCalls lower than the number of container request threads that can simultaneously invoke the bulkheaded method

Answer

If the bulkhead limit is smaller than the container thread pool, incoming request threads block waiting for a permit, eventually exhausting all container threads and causing starvation.

Question 4

A/B testing evidence for Spring Cloud Contract (consumer-driven contracts) versus integration tests demonstrates which primary benefit?

Accepted Answer

They detect API breaking changes in CI without deploying both services simultaneously, dramatically shortening the feedback loop

Answer

Consumer-driven contracts catch API incompatibilities at the provider's build stage without a full integrated environment, reducing feedback time compared to full integration test suites.

Question 5

Research into Spring Cloud Gateway route predicate ordering demonstrates that routes must be defined in which order to function correctly?

Accepted Answer

More-specific routes before less-specific (wildcard) routes to prevent broad predicates from shadowing narrower ones

Answer

Spring Cloud Gateway evaluates routes in definition order and uses the first match; placing wildcard routes first causes them to shadow all subsequently defined specific routes.

Spring Cloud Practice Test

Spring Cloud Practice Test

Spring Cloud Research & Evidence-Based Practice 5