gistfile1.rb

class ApplicationController < ActionController::Base
  unless Rails.application.config.consider_all_requests_local
    rescue_from ActionController::RoutingError,      :with => :render_404
    rescue_from ActiveRecord::RecordNotFound,        :with => :render_404
    rescue_from ActionController::UnknownAction,     :with => :render_404
    rescue_from ActionController::UnknownController, :with => :render_404
    rescue_from Exception,                           :with => :render_500
  end

  # Called from the bottom of config/routes.rb for all non-exiting routes
  def render_bad_route
    logger.error("Bad route '#{params['a']}'; '#{request.url}'; '#{request.remote_ip}';, '#{request.user_agent}'")
    common_error_handler(404, "404 Not Found", "The page you were looking for couldn't be found.")
  end
  
  private
  def render_404(exception)
    Exceptional.handle(exception)
    logger.error(exception)
    common_error_handler(404, "404 Not Found", "The page you were looking for couldn't be found.")
  end

  def render_500(exception)
    Exceptional.handle(exception)
    logger.error(exception)
    common_error_handler(500, "500 Internal Error", "An error has occurred on the page you were trying to access. We've been notified about this issue and we'll take a look at it shortly. We apologize for any inconvenience.")
  end

  def common_error_handler(code, short_message, long_message)
    @error_message = long_message
    respond_to do |format|
      format.html { render :template => 'application/error_template', :status => code }
      format.json { render :text     => long_message,                 :status => code }
    end
  end
end