Microservices Interservice Communication Strategies 3

Question 1

What problem does the Saga pattern primarily solve in microservices?

Accepted Answer

Managing distributed transactions without a global lock

Answer

Sagas coordinate a sequence of local transactions with compensating actions instead of a distributed lock.

Question 2

In a choreography-based saga, how do services coordinate?

Accepted Answer

By reacting to events each other publishes

Answer

Choreography relies on each service emitting and reacting to events without a central coordinator.

Question 3

What is a compensating transaction in a saga?

Accepted Answer

An action that semantically undoes a prior committed step

Answer

Since steps already committed, a compensating transaction reverses their effect logically.

Question 4

Which messaging delivery guarantee may deliver the same message more than once?

Accepted Answer

At-least-once

Answer

At-least-once retries until acknowledged, which can cause duplicates.

Question 5

What technique makes a consumer safe against duplicate message delivery?

Accepted Answer

Idempotent processing

Answer

Idempotent handlers produce the same result no matter how many times a message is processed.

Microservices Practice Test