Sequelize is returning integer as string

Question

I using nodejs v4 with sequelize, and I have a model like this:

var Device = sequelize.define('Device', {
id: {
  type: DataTypes.BIGINT,
  primaryKey: true,
  autoIncrement: true
},
tenantId: {
  type: DataTypes.BIGINT,
  allowNull: false
},
token: {
  type: DataTypes.STRING,
  allowNull: false
}
}, {
 tableName: 'devices'
});

When I select a device by id the type of id is a string, exemple:

Device.findById(9).then( function(result) {
  console.log(result.toJSON().id + 10);
});

The output will be 910, rather than 19, so I look at json and a saw this:

{
  id: "9"
  tenantId: "123"
  token: "adsadsdsa"
}

The id in found device is a string, but I defined it as a number...

Doesn't it should be { "id": 9 } ?

How can I select a device with the types that I defined previously?

Answer 1

I found a fix to this problem on sequelize repo.

https://github.com/sequelize/sequelize/issues/4523

The pg module used for sequelize returns bigint as string because bigints are not guaranteed to fit into js numbers. So I change my model to use integer (DataTypes.INTEGER)

Answer 2

BIGINT maximum value is 2^63-1, javascript can safely represent up to 2^53. To be on the safe side libraries return those numbers as strings.

If you want to have numbers instead of strings, you can use this library https://github.com/mirek/node-pg-safe-numbers which deals with this issue.