recursive transformer

transfomer

var groupBys = ["school", "class", "status"];
var totals = ["notSubmitted", "notGraded"];

var data = getData();

function makeTree(values, level) {
  level = level || 0;
  var levelKey = groupBys[level];
  var addedVals = {};
  if ((level + 1) === groupBys.length) {
    return getLeafNode(values, levelKey);
  } else {
    return _
      .chain(values)
      .map(function(value) {
        if (addedVals[value[levelKey]]) {
          return; //prevent same keys being added
        }
        addedVals[value[levelKey]] = true;

        //filter({school:"Chemsford High School"})
        var matchingItems = _.filter(values, {
          [levelKey]: value[levelKey]
        });

        //class
        var childrenKey = [groupBys[level + 1]];
      
        //obj = {"school": "Chemsford High School", "class":[...]}
        var obj = {
          [levelKey]: value[levelKey], [childrenKey]: makeTree(matchingItems, level + 1) // recursion
        };

        _.forEach(totals, function(ttl) {
          if (obj[ttl] === undefined) {
            console.log('groupBys[level + 1][ttl]', obj[childrenKey])
            obj[ttl] = _.sumBy(obj[childrenKey], ttl) || obj[childrenKey][ttl].length;
          }
        });
        return obj;
      })
      .compact() //remove falsy values (undefined)
      .value();
  }
}

function getLeafNode(values, levelKey) {
  var leaf = _.groupBy(values, levelKey);
  _.forEach(totals, (totalKey) => {
    leaf[totalKey] = leaf[totalKey] || [];
  });
  return leaf;
}

var result = makeTree(data);
console.log('result', result);

function getData() {
  return [{
    "firstName": "JammieGrp",
    "lastName": "Hawks",
    "studentID": "30301",
    "status": "notGraded",
    "school": "Chelmsford High School",
    "class": "11 ABC",
    "grade": 9
  }, {
    "firstName": "JammieGrp2",
    "lastName": "Hawks2",
    "studentID": "30301",
    "status": "notSubmitted",
    "school": "Chelmsford High School",
    "class": "10 EFG",
    "grade": 9
  }, {
    "firstName": "JammieGrp3",
    "lastName": "Hawks4",
    "studentID": "30301",
    "status": "notSubmitted",
    "school": "Chelmsford High School",
    "class": "12 HIG",
    "grade": 9
  }, {
    "firstName": "1JammieGrp",
    "lastName": "2Hawks",
    "studentID": "30301",
    "status": "notGraded",
    "school": "Bedford High School",
    "class": "11 HIG",
    "grade": 9
  }, {
    "firstName": "JammieGrp2",
    "lastName": "Hawks2",
    "studentID": "30301",
    "status": "notSubmitted",
    "school": "Bedford High School",
    "class": "11 HIG",
    "grade": 9
  }, {
    "firstName": "JammieGrp3",
    "lastName": "Hawks4",
    "studentID": "30301",
    "status": "notSubmitted",
    "school": "Bedford High School",
    "class": "11 HIG",
    "grade": 9
  }];
}

// function organizedData() {
//   return [{
//     "notSubmitted": 0,
//     "notGraded": 1,
//     "total": 1,
//     "school": "Chelmsford High School",
//     "classes": [{
//       "class": "10 ACSS",
//       "notSubmitted": 0,
//       "notGraded": 1,
//       "total": 1,
//       "statuses": [{
//         "total": 1,
//         "status": "notGraded",
//         "students": [{
//           "firstName": "JammieGrp",
//           "lastName": "Hawks",
//           "studentID": "30301",
//           "status": "notGraded",
//           "school": "Chelmsford High School",
//           "class": "10 ACSS",
//           "grade": 9
//         }]
//       }]
//     }]
//   }];
// }