Service Design · interview question
A bug appears around dto mapping. What is the strongest first debugging move?
Multiple choiceHardchapter-12-curatedpremiumservice-designdto-mapping
def to_order_summary(payload: dict[str, object]) -> dict[str, object]:
return {"id": payload["order_id"], "status": payload["state"]}Answer and explanation
Correct answer
D. Trace one concrete example, inspect the state transitions, and compare them to the intended rule before rewriting anything.
Why
That approach is reliable because it creates evidence. Skipping DTOs can make the service layer speak in partner-specific language forever.
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