Group arrays inside of an array

Question

I'm trying to group a list by an ID then inside that new list I'm trying to group a list of values based on that id in a certain time. I've manged to group by the id. I can't figure out what I need to do to group by the duration. Any help please

    const data = [
          {
            "name": "ted",
            "id": "1",
            "timestamp": 1512709024000
          },
          {
            "name": "seth",
            "id": "2",
            "timestamp": 1512754631000
          },
          {
            "name": "joe",
            "id": "1",
            "timestamp": 1512711000000
          },
          {
            "name": "phil",
            "id": "2",
            "timestamp": 1512754583000
          },
          {
            "name": "kane",
            "id": "1",
            "timestamp": 1512709065294

            },
        ]
 }


    {
    "result": {
      "1": [
        {
          "duration":18273
          "names": ["ted", "joe", "kane"],
          "startTime": 1512709065294
        }
      ]
    }
}

my efforts so far

        const d= data;
        const ids= data.reduce((ids, item) => {
        const id= (ids[item.id] || [])
        id.push(item);
        ids[item.id] = id
        return ids

       }, {})
       console.log('visitorIds',visitorIds)

Answer 1

Check this out:

const data = [
  {"name": "ted","id": "1","timestamp": 1512709024000},
  {"name": "seth","id": "2","timestamp": 1512754631000},
  {"name": "joe","id": "1","timestamp": 1512711000000},
  {"name": "phil","id": "2","timestamp": 1512754583000},
  {"name": "kane","id": "1","timestamp": 1512709065294},
];
    
    
const visitors = (data) => {
  const groupedData = data.reduce((acc, {id, name, timestamp}) => {
    acc[id] = (acc[id]) 
      ? {...acc[id], names: [...acc[id].names, name], times: [...acc[id].times, timestamp]}
      : {names: [name], times: [timestamp]};

    const startTime = Math.min(...acc[id].times);
    const finishTime = Math.max(...acc[id].times);
    const duration = finishTime - startTime;
    acc[id] = {...acc[id], duration, startTime};

    return acc; 
  }, {});

  Object.values(groupedData).forEach((obj) => delete obj.times);
  return groupedData;
};

console.log(visitors(data));
// {
//   '1': {
//     names: [ 'ted', 'joe', 'kane' ],
//     duration: 1976000,
//     startTime: 1512709024000
//   },
//   '2': {
//     names: [ 'seth', 'phil' ],
//     duration: 48000,
//     startTime: 1512754583000
//   }
// }