创建新的 object 数组并将对象合并到具有相同键值的数组 object 中

Question

This might seem a bit weird but I have a need to merge objects in an existing dataset into a new dataset grouped by a specific key value. Here's the dataset:

const object = [
  {
    id: 1,
    scheduledAt: '2022-09-20',
    organization: {
      name: 'Organization 1'
    }
  },
  {
    id: 2,
    scheduledAt: '2022-09-10',
    organization: {
      name: 'Organization 2'
    } 
  },
  {
    id: 3,
    scheduledAt: '2022-09-20',
    organization: {
      name: 'Organization 3'
    }
  }
]

Here is what I am after as the return dataset:

const objectMerged = {
  '2022-09-20': [
    {
      id: 1,
      scheduledAt: '2022-09-20',
      organization: {
        name: 'Organization 1'
      }
    },
    {
      id: 3,
      scheduledAt: '2022-09-20',
      organization: {
        name: 'Organization 3'
      }
    }
  ],
  '2022-09-10': [
    {
      id: 2,
      scheduledAt: '2022-09-10',
      organization: {
        name: 'Organization 2'
      } 
    }
  ]
}

I have tried many different ways but nothing seems to work correctly. Here's the latest code, which does not work:

const merged = []

object.forEach((item) => {
  if (!merged.length) {
    // if the return dataset is empty, add this item immediately
    merged.push({ [item.scheduledAt]: [item] }
  } else {
    // check if item already exists with the same scheduledAt as current object and if so, push it into that array as object
    // if does not exist, create new array entry with the new scheduledAt name

    const find = Object.keys(merged).map((k) => {
      console.log(`key ${k}`)
      console.log(merged[k])
    
      return Object.keys(merged[k]).map((key) => {
        console.log(`key2: ${key}`)
    
        return key === item.scheduledAt
      })
    })

    console.log(find)
  }
})

console.log(merged)

Any help is greatly appreciated. Thank you!

Answer 1

By using a reduce you can generate what you want. Please have a look:

 const object = [ { id: 1, scheduledAt: '2022-09-20', organization: { name: 'Organization 1' } }, { id: 2, scheduledAt: '2022-09-10', organization: { name: 'Organization 2' } }, { id: 3, scheduledAt: '2022-09-20', organization: { name: 'Organization 3' } }, ]; const objectMerged = object.sort((objectA, objectB) => objectA.scheduledAt.localeCompare(objectB.scheduledAt) ).reduce((acc, cur) => ({...acc, [cur.scheduledAt]: [...(acc[cur.scheduledAt] || []), cur, ], }), {}); console.log(objectMerged);