2009-08-04 17:16:03 +02:00
|
|
|
require 'erb'
|
|
|
|
|
|
2009-02-04 21:26:08 +01:00
|
|
|
module ActionController
|
2009-08-04 17:16:03 +02:00
|
|
|
# The Failsafe middleware is usually the top-most middleware in the Rack
|
|
|
|
|
# middleware chain. It returns the underlying middleware's response, but if
|
|
|
|
|
# the underlying middle raises an exception then Failsafe will log the
|
|
|
|
|
# exception into the Rails log file, and will attempt to return an error
|
|
|
|
|
# message response.
|
|
|
|
|
#
|
|
|
|
|
# Failsafe is a last resort for logging errors and for telling the HTTP
|
|
|
|
|
# client that something went wrong. Do not confuse this with the
|
|
|
|
|
# ActionController::Rescue module, which is responsible for catching
|
|
|
|
|
# exceptions at deeper levels. Unlike Failsafe, which is as simple as
|
|
|
|
|
# possible, Rescue provides features that allow developers to hook into
|
|
|
|
|
# the error handling logic, and can customize the error message response
|
|
|
|
|
# based on the HTTP client's IP.
|
2009-02-04 21:26:08 +01:00
|
|
|
class Failsafe
|
|
|
|
|
cattr_accessor :error_file_path
|
|
|
|
|
self.error_file_path = Rails.public_path if defined?(Rails.public_path)
|
|
|
|
|
|
|
|
|
|
def initialize(app)
|
|
|
|
|
@app = app
|
|
|
|
|
end
|
|
|
|
|
|
|
|
|
|
def call(env)
|
|
|
|
|
@app.call(env)
|
|
|
|
|
rescue Exception => exception
|
|
|
|
|
# Reraise exception in test environment
|
2009-08-04 17:16:03 +02:00
|
|
|
if defined?(Rails) && Rails.env.test?
|
2009-02-04 21:26:08 +01:00
|
|
|
raise exception
|
|
|
|
|
else
|
|
|
|
|
failsafe_response(exception)
|
|
|
|
|
end
|
|
|
|
|
end
|
|
|
|
|
|
|
|
|
|
private
|
|
|
|
|
def failsafe_response(exception)
|
|
|
|
|
log_failsafe_exception(exception)
|
2009-08-04 17:16:03 +02:00
|
|
|
[500, {'Content-Type' => 'text/html'}, [failsafe_response_body]]
|
2009-02-04 21:26:08 +01:00
|
|
|
rescue Exception => failsafe_error # Logger or IO errors
|
|
|
|
|
$stderr.puts "Error during failsafe response: #{failsafe_error}"
|
|
|
|
|
end
|
|
|
|
|
|
|
|
|
|
def failsafe_response_body
|
2009-08-04 17:16:03 +02:00
|
|
|
error_template_path = "#{self.class.error_file_path}/500.html"
|
|
|
|
|
if File.exist?(error_template_path)
|
|
|
|
|
begin
|
|
|
|
|
result = render_template(error_template_path)
|
|
|
|
|
rescue Exception
|
|
|
|
|
result = nil
|
|
|
|
|
end
|
2009-02-04 21:26:08 +01:00
|
|
|
else
|
2009-08-04 17:16:03 +02:00
|
|
|
result = nil
|
|
|
|
|
end
|
|
|
|
|
if result.nil?
|
|
|
|
|
result = "<html><body><h1>500 Internal Server Error</h1>" <<
|
|
|
|
|
"If you are the administrator of this website, then please read this web " <<
|
|
|
|
|
"application's log file to find out what went wrong.</body></html>"
|
2009-02-04 21:26:08 +01:00
|
|
|
end
|
2009-08-04 17:16:03 +02:00
|
|
|
result
|
|
|
|
|
end
|
|
|
|
|
|
|
|
|
|
# The default 500.html uses the h() method.
|
|
|
|
|
def h(text) # :nodoc:
|
|
|
|
|
ERB::Util.h(text)
|
|
|
|
|
end
|
|
|
|
|
|
|
|
|
|
def render_template(filename)
|
|
|
|
|
ERB.new(File.read(filename)).result(binding)
|
2009-02-04 21:26:08 +01:00
|
|
|
end
|
|
|
|
|
|
|
|
|
|
def log_failsafe_exception(exception)
|
|
|
|
|
message = "/!\\ FAILSAFE /!\\ #{Time.now}\n Status: 500 Internal Server Error\n"
|
|
|
|
|
message << " #{exception}\n #{exception.backtrace.join("\n ")}" if exception
|
|
|
|
|
failsafe_logger.fatal(message)
|
2010-05-25 19:45:45 +02:00
|
|
|
failsafe_logger.flush if failsafe_logger.respond_to?(:flush)
|
2009-02-04 21:26:08 +01:00
|
|
|
end
|
|
|
|
|
|
|
|
|
|
def failsafe_logger
|
|
|
|
|
if defined?(Rails) && Rails.logger
|
|
|
|
|
Rails.logger
|
|
|
|
|
else
|
|
|
|
|
Logger.new($stderr)
|
|
|
|
|
end
|
|
|
|
|
end
|
|
|
|
|
end
|
|
|
|
|
end
|
