javascript - 使用 lodash 进行多级分组

Question

我有下面的对象数组

const array = [
  {
    key: '11111',
    address: { city: 'NY', country: 'USA' },
    className: 'google.com',
    deviceId: 'aaaaa'
  },
  { 
    key: '11111',
    address: { city: 'NY', country: 'USA' },
    className: 'google.com',
    deviceId: 'aaaaa'
  },
  { 
    key: '33333',
    address: { city: 'NY', country: 'USA' },
    className: 'facebook.com',
    deviceId: 'aaaaa'
  },
  { 
    key: '11111',
    address: { city: 'NY', country: 'USA' },
    className: 'google.com',
    deviceId: 'ddddd'
  },
  {
    key: '22222',
    address: { city: 'Landon', country: 'UK' },
    className: 'stackoverflow.com',
    deviceId: 'ccccc'
  },
  {
    key: '22222',
    address: { city: 'Landon', country: 'UK' },
    className: 'stackoverflow.com',
    deviceId: 'ggggg'
  },
  {
    key: '22222',
    address: { city: 'Landon', country: 'UK' },
    className: 'stackoverflow.com',
    deviceId: 'fffff'
  }
]

我需要下面的输出

[
  {
    "keys": {
      "address": { "city": "NY", "country": "USA" },
      "className": "google.com",
      "key": "11111"
    },
    "count": 2
  },
  {
    "keys": {
      "address": { "city": "NY", "country": "USA" },
      "className": "facebook.com",
      "key": "33333"
    },
    "count": 1
  },
  {
    "keys": {
      "address": { "city": "Landon", "country": "UK" },
      "className": "stackoverflow.com",
      "key": "22222"
    },
    "count": 3
  }
]

那么这里到底发生了什么。

1) 如果用户使用相同的 key、address、className，我必须将用户视为唯一一个 和 deviceId。

然后

2) 我想用 key、className 和 address 分组并找到计数。

我该怎么做？

谢谢!!!请询问是否需要更多信息。

Answer 1

您可以将 groupBy 和 map 方法链接到第一个按键、地址和类名分组，然后再执行一个 groupBy 来分组和计算具有唯一 deviceId

的元素

const array = [{"key":"11111","address":{"city":"NY","country":"USA"},"className":"google.com","deviceId":"aaaaa"},{"key":"11111","address":{"city":"NY","country":"USA"},"className":"google.com","deviceId":"aaaaa"},{"key":"33333","address":{"city":"NY","country":"USA"},"className":"facebook.com","deviceId":"aaaaa"},{"key":"11111","address":{"city":"NY","country":"USA"},"className":"google.com","deviceId":"ddddd"},{"key":"22222","address":{"city":"Landon","country":"UK"},"className":"stackoverflow.com","deviceId":"ccccc"},{"key":"22222","address":{"city":"Landon","country":"UK"},"className":"stackoverflow.com","deviceId":"ggggg"},{"key":"22222","address":{"city":"Landon","country":"UK"},"className":"stackoverflow.com","deviceId":"fffff"}]

const result = _.chain(array)
  .groupBy(({ key, address: { city, country }, className }) => {
    return `${key}-${city}-${country}-${className}`
  }).map(e => {
    const [{ key, address, className }] = e;
    return {
      keys: { key, address, className },
      count: _.keys(_.groupBy(e, 'deviceId')).length
    }
  })

console.log(result)

<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.10/lodash.js"></script>