DoorDash VO 面试真题解析：Get User Bootstrap Response（聚合接口 / JSON 组装）

GET /api/bootstrap

Request input: User Id

Response: address, consumer, and payment data

{
  "consumerId": "1bef988e-e544-11ed-b5ea-0242ac120002",
  "roles": [],
  "defaultCard": {
    "lastFourDigits": "1234",
    "expirationYear": "2024",
    "expirationMonth": "01",
    "fingerPrint": "f3cd76f4-e544-11ed-b5ea-0242ac120002",
    "createdAt": "2022-07-15"
  },
  "availableGiftCardCredits": "0.0",
  "address": "Foo Bar, 303 2nd Street, San Francisco, CA 94105"
}

Additional APIs referenced in the prompt:

• GET /api/consumers/{userId}
• GET /api/payment_methods/
• GET /api/address/

这道题考察的是接口聚合与响应对象组装：根据输入的 user_id，分别获取 consumer、支付方式和地址信息，再拼成一个统一的 bootstrap 响应。实现时重点是字段映射要准确，例如 consumerId、defaultCard、giftCards、address 等字段需要从不同子接口中取值并保持格式一致。题目本质上更偏向于对象封装、数据整合以及 API 返回结构设计，而不是复杂算法；如果用类来表示各个 response，再在顶层统一组装，会更清晰、也更符合面试场景。