The Cucumber Book, 2nd Edition

Refactoring to Use a Database

In our current system, the balance of the single account is stored in a file and read and written by the BalanceStore class. In our new design, we will make the Account responsible for reading the balance straight out of a database instead. It’s refactoring time again!

We’ll start by moving the Account class into its own lib/account.rb file and make it an ActiveRecord class:

databases/01/lib/account.rb

require 'active_record'
ActiveRecord::Base.establish_connection(:adapter => 'sqlite3',
                                        :database => 'db/bank.db')
ActiveRecord::Migrator.migrate("db/migrate/")
class Account < ActiveRecord::Base
  validates_uniqueness_of :number
  def queue
    @queue ||= TransactionQueue.new
  end

  def ...