function returning undefined instead of bool

Question

Probably missing something simple here but cant for the life of me figure out why the below function is returning undefined.

  var isOrphanEan = function isOrphanEan (ean) {

    Products.findOne({
      'ean': ean
    }, function (err, product) {
        return product.orphan;
    });
  }

  isOrphanEan(12345); //returns undefined

example of product

{ 
_id: 55ad6b442afbebe82d077a04,
  orphan: true
  }

edit:

console.logging product returns:

{ _id: 55ad6b442afbebe82d077a04,
  ean: 4006643097328,
  aw_product_id: 3295182687,
  product_name: 'Multipower Shaker Neutral',
  product_brand: 'Multipower UK',
  product_description: '',
  img_sml: 'http://images.productserve.com/noimage.gif',
  img_lrg: '',
  rating: '',
  merchant_id: 2926,
  price_current: 'GBP4.99',
  price_rrp: '',
  aff_link: 'http://www.awin1.com/pclick.php?p=3295182687&a=234945&m=2926',
  direct_link: 'http://www.multipower.com/uk/product/multipower-shaker-09732/neutral',
  merchant_product_id: '09732',
  aw_image_url: '',
  orphan: true,
  created_at: Mon Jul 20 2015 22:42:28 GMT+0100 (BST),
  updated_at: Thu Oct 08 2015 23:20:35 GMT+0100 (BST),
  __v: 0 }

What happens when you `console.log(product)` ? It may just be that `Products` is not finding any item given the search criteria. — David Li, Oct 12 '15 at 22:31
Is the `ean` property stored as integer? Maybe try ean.toString() when you search. — Travis, Oct 12 '15 at 22:32
Ohhh @MinusFour is right. You need to use a callback function in isOrphanEan since `Products` is fetching your item asynchronously. — David Li, Oct 12 '15 at 22:33
`isOrphanEan` should take a callback that is called when `Product.findOne` has completed, rather than returning a value. — joews, Oct 12 '15 at 22:33
@joews i would surmise this is an even better one: http://stackoverflow.com/questions/6180896/how-to-return-mongoose-results-from-the-find-method — Daemedeor, Oct 12 '15 at 22:38

score 1 · Accepted Answer · answered Oct 12 '15 at 22:40

1

Use callbacks approach to cope with async responses:

var isOrphanEan = function isOrphanEan (ean, cb) {

    Products.findOne({
      'ean': ean
    }, cb);
}

  isOrphanEan(12345, function(err, product) {
     console.log(product.orphan);  
  });

answered Oct 12 '15 at 22:40

Daniel Conde Marin

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score -1 · Answer 2 · answered Oct 12 '15 at 22:34

You are using a callback. Function isOrphanEan() does not return anything, rather findOne() will call the callback when the data becomes available. You need to process you product.orphan in the unnamed callback.

function returning undefined instead of bool

2 Answers2