Ruby on Rails model interfaces

artifact_interface_concern.rb

# frozen_string_literal: true

module ArtifactInterface
  extend ActiveSupport::Concern
  extend Interfaceable

  def key
    raise NotImplementedError
  end

  def uid
    raise NotImplementedError
  end

  def display_name
    raise NotImplementedError
  end

  def display_type
    raise NotImplementedError
  end

  def display_svg_file
    raise NotImplementedError
  end

  def display_url
    raise NotImplementedError
  end
end

interfaceable_concern.rb

# frozen_string_literal: true

module Interfaceable
  class InterfaceNotImplementedError < NoMethodError
  end

  def verify(model, instance = nil)
    return if verifying_ar_model_but_migrations_not_run?

    instance ||= model.new
    unimplemented_instance_methods = instance_methods - instance.methods

    return true if unimplemented_instance_methods.empty?

    methods_not_implemented(model, unimplemented_instance_methods)
  end

  private

  def methods_not_implemented(klass, *methods)
    fail InterfaceNotImplementedError,
      "#{klass} needs to implement #{methods.join(", ")} for interface #{name}!"
  end

  def verifying_ar_model_but_migrations_not_run?
    return false unless defined? ActiveRecord::Base
    ActiveRecord::Base.connection.data_sources.empty?
  end
end

jira_issue.rb

class Jira::Issue < ApplicationRecord
  # ...
  
  ArtifactInterface.verify(self)
end