Ruby service object examples

omni_authorizer.rb

class OmniAuthorizer
  def self.call(params)
    new(SlackAPI.new).call(params)
  end

  def self.build_for_facebook(params)
    new(FacebookAPI.new).call(params)
  end

  def initialize(api)
    @api = api
  end

  def call(params)
    api.create_user(params[:email])
  end

  private

  def prepare_user(user)
    # TODO
  end
end


# we can user service in 2 different contextes like SlackAPI or FacebookAPI
OmniAuthorizer.call(params)
OmniAuthorizer.build_for_facebook(params)



# How to test service (more complex testing)
OmniAuthorizer.new.call(params)

let(:omni_authorizer) { instance_double(OmniAuthorizer) }

expect(OmniAuthorizer).to receive(:new).and_return(omni_authorizer)
except(omni_authorizer).to receive(:call).with(params)



# How to test service (easier testing)
OmniAuthorizer.call(params)

except(OmniAuthorizer).to receive(:call).with(params)