Get all combination of a nested object

Question

I have JSON data which can be an object/array of recursively nested object or array. The value of an array can not be null, but a value in an object can be null. And I would like to return all combinations of these keys and values through depth-first search.

For example:

var data = {
  "title": {
     "original": "Hitchhiker",
     "more": ["HGTTG"],
     "link": null
  },
  "date": ["20150101", "20160101"]
}

The data's length and depth is arbitrary, and the combination result I want is something like this:

["title-original-Hitchhiker", "title-more-HTTG", "title-link", "date-20150101", "date-20160101"]

What I came up with is recursive:

function nestedObjectToArray(obj) {
  if (typeof(obj) != "object"){
    return [obj];
  }
  var result = [];
  if (obj.constructor == Array){
    for (var i = 0; i <obj.length; i++){
      if (obj[i]){
        var temp = nestedObjectToArray(obj[i]);
        for (var j = 0; j < temp.length; j++){
          result.push(temp[j]);
        }
      }
    }
  } else {
    for (var i in obj){
      if (obj.hasOwnProperty(i)) {
        if (obj[i] == null){
          result.push(i);
        } else {
          var temp = nestedObjectToArray(obj[i]);
          for (var j = 0; j < temp.length; j++){
            result.push(i+"-"+temp[j]);
          }
        }
      }
    }
  }
  return result;
}

Would you have a better/more elegant solution than this chunk of conditions, loops and recursion? I can use any library if it's more convenient.

Answer 1

A little refactor solution can be

function nestedObjectToArray(obj) {
    if (typeof(obj) !== "object"){
        return [obj];
    }
    var result = [];
    if (obj.constructor === Array){
        obj.map(function(item) {
            result = result.concat(nestedObjectToArray(item));
        });
    } else {
        Object.keys(obj).map(function(key) {
            if(obj[key]) {
                var chunk = nestedObjectToArray(obj[key]);
                chunk.map(function(item) {
                    result.push(key+"-"+item);
                });
            } else {
                result.push(key);
            }
        });
    }
    return result;
}