vendor/rails/actionpack/lib/action_controller/failsafe.rb

   1 module ActionController
   2   class Failsafe
   3     cattr_accessor :error_file_path
   4     self.error_file_path = Rails.public_path if defined?(Rails.public_path)
   5
   6     def initialize(app)
   7       @app = app
   8     end
   9
  10     def call(env)
  11       @app.call(env)
  12     rescue Exception => exception
  13       # Reraise exception in test environment
  14       if env["rack.test"]
  15         raise exception
  16       else
  17         failsafe_response(exception)
  18       end
  19     end
  20
  21     private
  22       def failsafe_response(exception)
  23         log_failsafe_exception(exception)
  24         [500, {'Content-Type' => 'text/html'}, failsafe_response_body]
  25       rescue Exception => failsafe_error # Logger or IO errors
  26         $stderr.puts "Error during failsafe response: #{failsafe_error}"
  27       end
  28
  29       def failsafe_response_body
  30         error_path = "#{self.class.error_file_path}/500.html"
  31         if File.exist?(error_path)
  32           File.read(error_path)
  33         else
  34           "<html><body><h1>500 Internal Server Error</h1></body></html>"
  35         end
  36       end
  37
  38       def log_failsafe_exception(exception)
  39         message = "/!\\ FAILSAFE /!\\  #{Time.now}\n  Status: 500 Internal Server Error\n"
  40         message << "  #{exception}\n    #{exception.backtrace.join("\n    ")}" if exception
  41         failsafe_logger.fatal(message)
  42       end
  43
  44       def failsafe_logger
  45         if defined?(Rails) && Rails.logger
  46           Rails.logger
  47         else
  48           Logger.new($stderr)
  49         end
  50       end
  51   end
  52 end