Associate in sequelize js

User Model (file)

module.exports = function(sequelize, DataTypes){
    var User = sequelize.define(
        'User', {
            name: {
                type: DataTypes.STRING,
                allowNull: false
            }
        },
        {
            classMethods:{
                associate:function(models){
                    User.hasMany(models.Comment, { foreignKey: 'userId'} );
                }
            }
        }

    );
    return User;
};
Comment Model (file):

module.exports = function(sequelize, DataTypes){
    var Comment = sequelize.define(
        'Comment', {
            text: {
                type: DataTypes.STRING,
                allowNull: false
            }
        },
        {
            classMethods:{
                associate:function(models){
                    Comment.belongsTo(models.User, { foreignKey:'userId'} );
                }
            }
        }

    );
    return Comment;
};
You don't have to set the foreignkey, sequelize will handle it if you don't specify the foreignkeys.

Then in the query:

models.Comment.find({
        where: { id: id },
        include: [
            models.User
        ],
        limit: 1
    })