Multi Step Processes medium
Standard message queues (like SQS or RabbitMQ) guarantee 'At-Least-Once' delivery. What implication does this have for your consumer logic?
- A You must use a FIFO queue.
- B You must implement Idempotency, because the same message might be delivered twice.
- C Messages will be encrypted.
- D Messages will arrive in strict order.
Answer: B. You must implement Idempotency, because the same message might be delivered twice.
To ensure a message isn't lost, queues might deliver it multiple times (e.g., if an ACK is lost). The consumer must be able to process the same message ID multiple times without corrupting data.
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