sequelClass.js

const Model = require('sequelize').Model;

class User extends Model {
  
  columns: {
    id: {
      autoIncrement: true,
      primaryKey: true,
      type: Model.DataTypes.INTEGER(10)
    },

    username: Model.DataTypes.STRING,
    password: Model.DataTypes.STRING(40)
  },

  underscored: true,
  freezeTableName: true,
    
  static checkUsernameExists (username) {
    return User.count({where: {username}});
  }

  set password (password) {
    let hash = crypto.createHash('sha1').update(password).toString('hex');
    this.setDataValue('password', hash);
  }
}

module.exports = (sequelizeInstance) => {
  sequelizeInstance.importClass(User)
}