hard20 pts · first answer countsdistributed-systemsreliability

Saving data and publishing an event

After saving an order, the API publishes an OrderCreated event to a message queue. Sometimes the server crashes between the two steps and the email service never hears about the order. What is the reliable design?

A.Publish the event first, then save the orderB.Wrap both calls in a JavaScript try/catchC.Retry the publish in the same request 10 timesD.Transactional outbox: insert the event into an outbox table in the same database transaction as the order, and let a separate worker publish and mark it sent

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