automatically define Rails render_* methods for all possible HTTP responses

render_status_codes.rb

class ApplicationController < ActionController::Base
  protected

  # Define render_xxx methods for all known status codes.
  ActionController::StatusCodes::SYMBOL_TO_STATUS_CODE.each do |symbol, code|
    define_method "render_#{symbol}" do |*args|
      respond_to do |format|
        format.html{render_error_html_file(code, (args.first || {}))}
        format.all{head symbol}
      end
      true
    end
  end

  # Render an html file under public/<Status code>.html, or default to just
  # sending the status as a header.
  def render_error_html_file code, options={}
    file = File.join(RAILS_ROOT, 'public', "#{code}.html")
    if File.exist? file
      render options.reverse_merge(:file => file, :layout => false, :status => code)
    else
      head code
    end
  end
end