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

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 — Shih-Min Lee, Sep 24 '15 at 06:27
Thanks, this way works too. but i think less code is better, so i want to use @qqilihq approach. — M2sh, Sep 24 '15 at 06:37

score 12 · Accepted Answer · edited Aug 10 '21 at 14:03

12

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.

edited Aug 10 '21 at 14:03

Dan

15
6

answered Sep 24 '15 at 06:25

qqilihq

10,794
7
48
89

How would I enumerate over object properties with for ... in? – velop Apr 23 '16 at 13:31

score 1 · Answer 2 · edited Jun 21 '19 at 16:27

1

Try

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

It worked for me

edited Jun 21 '19 at 16:27

Suraj Kumar

5,547
8
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answered Jun 21 '19 at 16:04

Adam Falchetta

65
1
9

score 1 · Answer 3 · answered Nov 22 '22 at 18:25

1

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)
 }

answered Nov 22 '22 at 18:25

jeffgamedev

136
2
5

Mongoose for var in loop in subdocuments

3 Answers3