Mongoose for var in loop in subdocuments

Question

I created this schema with mongoose Schema :

socialAccount =  new Schema({
    socialNetwork : { type : String , required : true},
    userid : { type : Number,  required :  true },
    username : String
},{_id : false});
person = new Schema({
    id : { type : Number,  unique : true, required : true , dropDups :  true },
    firstname : String,
    lastname : String,
    socialAccounts : [socialAccount],
    updated : { type : Date, default : Date.now },
    enable : { type : Boolean , default : true },       
});

When i get data with findOne method the result looks like this (in console.log()) :

{ 
  id: 1,
  firstname: 'example name',
  lastname: 'example last',
  enable: true,
  updated: Thu Sep 24 2015 09:40:17 GMT+0330 (IRST),
  socialAccounts: 
   [ { socialNetwork: 'instagram',
       userid: 1234567,
       username: 'example' } ] }

SO, When i want to iterate on subdocument socialAccounts with for var in loop structure & view data with console.log(), it returns some other objects & function & only the first one is subdocument object.
How can i get only first element of socialAccounts subdocument with this for-loop iterate method.

Thanks

Turbary

I think Person.findOne returns a bson file and you might want to JSON.parse(JSON.stringify()) the document to make it an normal array object – Oestrogen

Thanks, this way works too. but i think less code is better, so i want to use @qqilihq approach. – Turbary

Answer 1

Use an indexed for loop, instead of a for … in:

for (let i = 0; i < socialAccounts.length; i++) {
    var currentAccount = socialAccounts[i];
}

The for … in loop will enumerate additional object properties as you noticed and should not be used for arrays. See this question and answers.

Coastline

How would I enumerate over object properties with for ... in? – Rosenquist

Answer 2

Try

.findOne(...() => {})

It worked for me

Aurify

Answer 3

Using ES6, you can iterate through the objects of array without the mess of handling the index and array access by using let obj of arr.

 for (let item of arr) {
  console.log(item)
 }

Deflagrate