How to group an array of objects

Issue

I have an array of objects in the below format

const Employer = [{'company': 'ABC','location': 'Phase 1','year': '2012'}, 
    {'company': 'ABC','location': 'Phase2', 'year': '2013'}, 
    {'company': 'XYZ','location': 'Phase3','year': '2012'}];

And expected output is

  {
      'ABC':{
        'company': 'ABC',
         data:[
          {'location':'Phase1','year':2012},
          {'location':'Phase2', 'year':2013}]
         },
      'XYZ':{
        'company': 'ABC',
         data:[
          {'location':'Phase3','year':2012}]
      }           
    }

What I have tried is

name = 'Angular';
  groupedData:any;
  
  ngOnInit(){
    const Employer = [{'company': 'ABC','location': 'Phase 1','year': '2012'}, 
    {'company': 'ABC','location': 'Phase2', 'year': '2013'}, 
    {'company': 'XYZ','location': 'Phase3','year': '2012'}];
  
    this.groupedData = _.mapValues(_.groupBy(Employer, 'company'))    
    console.log(this.groupedData)
}
}

Output:
{
  "ABC": [
    {
      "company": "ABC",
      "location": "Phase 1",
      "year": "2012"
    },
    {
      "company": "ABC",
      "location": "Phase2",
      "year": "2013"
    }
  ],
  "XYZ": [
    {
      "company": "XYZ",
      "location": "Phase3",
      "year": "2012"
    }
  ]
}

Here again I need to group the data. Can anyone help me to get the expected output

Solution

    const Employers = [{ 'company': 'ABC', 'location': 'Phase 1', 'year': '2012' },
    { 'company': 'ABC', 'location': 'Phase2', 'year': '2013' },
    { 'company': 'XYZ', 'location': 'Phase3', 'year': '2012' }];

    const output: any = {};
    for (const e of Employers) {
        if (output[e.company]) {
            output[e.company].data.push({ location: e.location, year: e.year });
        } else {
            output[e.company] = { company: e.company, data: [{ location: e.location, year: e.year }] };
        }
    }

    console.log(output);

Answered By - zainhassan