分组依据并保留原始字段

Question

我看到在mongodb聚合中，特别是在$group中，我们可以使用累加器来创建新字段。但我想要旧钥匙

假设我有这样的数据

[
   { name: "My Plan 101", billingCycle: 'day', amount: 1, credits: 100, price: 7 },
   { name: "My Plan 102", billingCycle: 'day', amount: 1, credits: 150, price: 10 },
   { name: "My Plan 103", billingCycle: 'day', amount: 2, credits: 150, price: 15 },
   { name: "My Plan 104", billingCycle: 'month', amount: 3, credits: 150, price: 15 },
   { name: "My Plan 105", billingCycle: 'month', amount: 3, credits: 200, price: 20 },
]

那么聚合应该是这样的

[
    'day': { 
        '1': [{ name: 'My Plan 101' }, { name: 'My Plan 102' }],
        '2': [{ name: 'My Plan 103' }]
    },
    'month': {
        '3': [{ name: 'My Plan 104' }, { name: 'My Plan 105' }]
    }
]

Answer 1

我尝试了很多mongodb聚合，但是不能解决这个问题，所以我使用了lodash。

let plans = await Plan.find()
plans = _.groupBy(plans, 'billingCycle');

for (const billingCyle in plans) {
  let $plans = plans[billingCyle];
  plans[billingCyle] = _.groupBy($plans, "amount")
}
console.log(plans)

上面的片段解决了我的问题