CPSA Architectural Patterns and Styles 3

Question 1

Which microservices pattern coordinates a sequence of local transactions across multiple services using events or messages to maintain data consistency?

Accepted Answer

Saga Pattern

Answer

The Saga pattern breaks a distributed transaction into a series of local transactions, each publishing events that trigger the next step, with compensating transactions for rollback.

Question 2

In microservices architecture, an API Gateway primarily serves which function?

Accepted Answer

Acting as a single entry point that routes, aggregates, and cross-cuts concerns for client requests

Answer

An API Gateway consolidates routing, authentication, rate limiting, and response aggregation so clients interact with one endpoint instead of many services.

Question 3

The Circuit Breaker pattern in distributed systems is designed to prevent which specific failure mode?

Accepted Answer

Cascading failures caused by repeatedly calling a failing remote service

Answer

A Circuit Breaker monitors failure rates and, after a threshold is exceeded, stops forwarding calls to the failing service, giving it time to recover and preventing overload.

Question 4

What is the key characteristic that distinguishes Choreography-based sagas from Orchestration-based sagas?

Accepted Answer

In choreography, each service reacts to events autonomously without a central controller

Answer

In choreography, services react to domain events published by other services without a central orchestrator, leading to decentralized and loosely coupled coordination.

Question 5

The Backend for Frontend (BFF) pattern solves which architectural problem?

Accepted Answer

Tailoring API interfaces to the specific needs of each client type (e.g., mobile vs. web)

Answer

BFF creates a dedicated backend for each type of frontend client, allowing each to evolve independently with an API optimized for its unique needs.

CPSA Exam Practice Test

CPSA Exam Practice Test

CPSA Architectural Patterns and Styles 3