sg_node_mapper.rb

require 'execjs'

class SgNodeMapper

  def method_missing(method, *args, &block)
    context.call("nodemapper.#{method.to_s.camelize(:lower)}", *args)
  end

  private

  def context
    @context ||= ExecJS.compile(source)
  end

  def source
    @source ||= File.read(source_path)
  end

  def source_path
    Rails.root.join('vendor', 'sg_node_mapper', 'nodemapper.js')
  end
end