company.rb

class Company < ActiveRecord::Base

  before_create :generate_api_token

  attr_accessible :name, :owner, :owner_id

  validates :name, presence: true, uniqueness: { case_sensitive: false }, :length => { :minimum => 5, :maximum => 40 }
  validates :owner, presence: true
  validates :owner_id, presence: true

  has_many :orders
  has_many :users

  private
    def generate_api_token
      begin
        self.token = SecureRandom.urlsafe_base64
      end while self.class.exists?(token: self.token)
    end

end

company_spec.rb

  describe "when email is not downcased" do
    before { @company.save }

    it "should be saved as all lowercase" do
      saved_company = Company.find(@company.id)
      @company.name = "Another name"
      @company.save
      expect(@company.token).to eq saved_company.token
    end
  end