Manipulating data from array of objects inside object to array of objects inside array

Question

I'm trying to manipulate data, and I'd need a solution for this

Tried mapping in different ways, but none of them worked.

This is the input data:

   data_input = {
    2000: [{
            _id: 0,
            name: "Jeff",
            value: 130,
            year: 2000
        },
        {
            _id: 1,
            name: "Bill",
            value: 30,
            year: 2000
        }
    ],
    2001: [{
            _id: 0,
            name: "Jeff",
            value: 20,
            year: 2001
        },
        {
            _id: 1,
            name: "Bill",
            value: 100,
            year: 2001
        }
    ]
 }

Here is the expected result:

   data_output = [{
        year: 2000,
        year_data: [{
                _id: 0,
                name: "Jeff",
                value: 130
            },
            {
                _id: 1,
                name: "Bill",
                value: 30
            }
        ]
    },
    {
        year: 2001,
        year_data: [{
                _id: 0,
                name: "Jeff",
                value: 20
            },
            {
                _id: 1,
                name: "Bill",
                value: 100
            }
        ]
    }
 ]

Answer 1

You can use Object.entries and map

Here idea is :-

• with object.entries get the key value from object and map on them to change it to needed format
• Key is used as year property in desired structure and value is used as year_data

 let data = {2000: [{ _id: 0, name: "Jeff", value:130, year: 2000 }, { _id: 1, name: "Bill", value:30, year: 2000 } ] , 2001 : [{ _id: 0, name: "Jeff", value: 20, year: 2001 }, {_id:1, name: "Bill", value: 100, year: 2001 } ]} let final = Object.entries(data).map(([year, year_data]) => ({ year, year_data: year_data.map(({year,...rest})=>rest)})) console.log(final) 

Answer 2

You could map the values and destructure the year from the rest object.

 var data_input = { 2000: [{ _id: 0, name: "Jeff", value: 130, year: 2000 }, { _id: 1, name: "Bill", value: 30, year: 2000 }], 2001: [{ _id: 0, name: "Jeff", value: 20, year: 2001 }, { _id: 1, name: "Bill", value: 100, year: 2001 }] }, result = Object .values(data_input) .map(a => ({ year: a[0].year, year_data: a.map(({ year, ...rest }) => rest) })); console.log(result); 

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Answer 3

try this

  data_input = { 2000: [{ _id: 0, name: "Jeff", value: 130, year: 2000 }, { _id: 1, name: "Bill", value: 30, year: 2000 } ], 2001: [{ _id: 0, name: "Jeff", value: 20, year: 2001 }, { _id: 1, name: "Bill", value: 100, year: 2001 } ] } var output = Object.keys(data_input).map(item => { let year_data = data_input[item].map(data => { delete data.year return data }); return { year: item, year_data:year_data } }); console.log(output);