JSON to match key/values and get the total values for each key

Question

I need help displaying a total of sessionTime to every goalName from an api I have created. I have tried mapping and reducing but was only able to get the total sessionTime.

I expect the results to come like this:
Learn Italian : 6
Parla con il mio amico in Italiano : 1

"records": [
    {
      "sessionTime": 1,
      "goalName": "Learn Italian",
      "timeStapmed": "10:08:23",
      "date": "11/08/2021",
      "id": 1
    },
    {
      "sessionTime": 5,
      "goalName": "Learn Italian",
      "id": "PFKFKZ",
      "timeStapmed": "10:14:48",
      "date": "11/08/2021"
    },
    {
      "sessionTime": 1,
      "goalName": "Parla con il mio amico in italiano",
      "id": "aP_g1-",
      "timeStapmed": "10:21:28",
      "date": "11/08/2021"
    }
  ]

Answer 1

I think you're looking for an array#reduce loop,

records.reduce(
  (acc, { sessionTime, goalName }) =>
    acc?.[goalName]
      ? { ...acc, [goalName]: acc[goalName] + sessionTime }
      : { ...acc, [goalName]: sessionTime },
  {}
);

we can go though each object and keep a sum of their values in the acc variable.

Full code:

let records = [
  {
    sessionTime: 1,
    goalName: "Learn Italian",
    timeStapmed: "10:08:23",
    date: "11/08/2021",
    id: 1,
  },
  {
    sessionTime: 5,
    goalName: "Learn Italian",
    id: "PFKFKZ",
    timeStapmed: "10:14:48",
    date: "11/08/2021",
  },
  {
    sessionTime: 1,
    goalName: "Parla con il mio amico in italiano",
    id: "aP_g1-",
    timeStapmed: "10:21:28",
    date: "11/08/2021",
  },
];


let newRecords = records.reduce((acc, {sessionTime, goalName}) => acc?.[goalName] ? {...acc, [goalName]: acc[goalName] + sessionTime} : {...acc, [goalName]: sessionTime}, {})

console.log(newRecords)