How to save an object inside mongodb

I have created a form where i have certain fields.I also have a field that contains an array of fields within."req.body.lead" output of the field is as:

// output of console.log("req.body.lead",req.body.lead);
     business_address_attributes: 
      { address_type: 'Business',
        street1: 'Street 1...',
        street2: 'Street 2...',
        city: 'City...',
        state: 'State...',
        zipcode: 'Zip Code...',
        country: '' },

I can store the entire object inside another object as:

      var address = new Addresses(req.body.lead.business_address_attributes);

Inside mongodb i have declared a field as:

   business_address_attributes : [Addresses],
   //Note: [Addresses] refers to address class

Now when i try to store the inside monogdb using following, I am getting error,unable to save lead

var lead = new Leads(req.body.lead);
var address = new Addresses(req.body.lead.business_address_attributes);
lead.business_address_attributes.$push(address);
lead.save();
// console.log(lead.business_address_attributes) now gives following output:
    [ { address_type: 'Business',
  street1: 'Street 1...',
  street2: 'Street 2...',
  city: 'City...',
  state: 'State...',
  zipcode: 'Zip Code...',
  country: '',
  _id: 4f857a2e491383dc64000008 } ]

I don't know how to solve the problem.Can someone help.

My solution of this problem was to declare the field with array of documents as a reference array.

Create a schema for Address document:

  var AddressSchema = new Schema({
     //attributes
  });

and create a model:

mongoose.model('address', AddressSchema)

Now in the parent document you can say

business_address_attributes : [{ type: Schema.ObjectId, ref: 'address' }]

When creating a new document, create Address document first, save it, get ID of a saved doc and push it into lead.business_address_attributes.

To get back a document with addresses instead of just IDs, use mongoose's populate('business_address_attributes') method.