Nested loop to transform MongoDB results

Question

I have the following structure returned from MongoDB:

[Class]
 0:Class // -> this.data.userInfo as seen below in the code
 _id: "ksihHTAjdhsA9"
 createdAt:Tue Mar 29 2016 13:03:45 GMT-0400 (EDT)
 weightData: Array[3]
 0: Class
 name: "my name 1"
 value: "myval1"
 weight: 154
 1: Class
 name: "my name 2"
 value: "myval2"
 weight: 191
 2: Class
 name: "my name 3"
 value: "myval3"
 weight: 210

I need to loop through the weightData nested array and store the name and value in a dictionary variable to be used in a dropdown later. I have it working, however, I feel like this could be more efficient.

var dict = [];
_.each(this.data.userInfo, info => {
 if (info) {
 _.each(info.weightData, weightInfo => {
 dict.push({
 "name": weightInfo.name, 
 "value": weightInfo.value,
 "weight": weightInfo.weight
 });
 });
 }
});
console.log(dict);
/*
[Object, Object, Object]
 0:Object
 name: "my name 1"
 value: "myval1"
 weight: 154
 1:Object
 name: "my name 2"
 value: "myval2"
 weight: 191
 2:Object
 name: "my name 3"
 value: "myval3"
 weight: 210
*/

Answer 1

It looks like you are basically doing a filter + flatMap. You can also use destructing:

var dict = _(this.data.userinfo).filter(Boolean).flatMap(info => {
 return info.weightdata.map(({name, value, weight}) => {
 return {name, value, weight};
 });
}).value();