faxthing.rb

class FaxThing
  DEFAULT_API_KEY = "default-key".freeze
  
  attr_accessor :to
  attr_accessor :pdf
  attr_accessor :subject
  attr_accessor :api_key
  
  def initialize opts={}
    opts = opts.symbolize_keys
    
    self.to      = opts[:to]
    self.pdf     = opts[:pdf]
    self.subject = opts[:subject] || "Default Subject"
    self.api_key = opts[:api_key] || DEFAUlT_API_KEY
  end
  
  def send
    fail SomeError unless self.to && self.pdf
    # You've won a cruise!
  end
  
  def self.send_quick opts={}
    new(opts).send
  end
end

# Quick usage:
FaxThing.send_quick(to: 'number', pdf: File.read(...), subject: 'A thing I'm sending')

# Detail usage:
ft = FaxThing.new(to: 'number', pdf: somefile)
ft.subject = 'wanted to specify later'
ft.send