Get Date from Nested Array of Objects and set that date as an Key in Node.js-CodePudding

I'm using Node.js I have data like this:

const data= [
        {"id":"1","date":"2022-09-07T15:56:32.279Z","req_id":"98"},
        {"id":"2","date":"2022-09-08T15:48:19.075Z","req_id":"97"},
        {"id":"3","date":"2022-09-06T15:48:19.073Z","req_id":"96"}
       {"id":"4","date":"2022-09-06T15:48:19.073Z","req_id":"96"}
        ]

I want data in this format:

expected Output:

"2022-09-06":[
{"id":"4","date":"2022-09-06T15:48:19.073Z","req_id":"96"},
{"id":"3","date":"2022-09-06T15:48:19.073Z","req_id":"96"}
]
"2022-09-08":[
{"id":"2","date":"2022-09-08T15:48:19.075Z","req_id":"97"}
]
"2022-09-07":[
{"id":"1","date":"2022-09-07T15:56:32.279Z","req_id":"98"}
]

CodePudding user response：

Straightforward solution using regex:

let result = new Map();
for (const item of data) {
    let date = item['date'].match(/\d{4}-\d{2}-\d{2}/)[0];
    let items = result.get(date) || [];
    items.push(item);
    result.set(date, items)
}

CodePudding user response：

Assuming the dates are always in the same format, I would do something like this:

function mapData(data){
    // returns the given date as an string in the "