RescueRegistry improves error handling with Rails while still hewing as close to the defaults as possible.
rescue_from works fine, but it it's a big hammer. Using it completely bypasses Rail's built-in exception handling middlewares,
which actually do some nice things for us (e.g. automatically handling different data formats). RescueRegistry allows the built-in
middleware to handle the exceptions but with our custom handlers.
Rails also has some built-in support for assigning different exception classes to status types (See config.action_dispatch.rescue_responses).
Unfortunately, all this allows you to do is assign a status code. If you want more complex error handling, or to use different codes in
different controllers, you're out of luck. With RescueRegistry you can register an exception with a custom handler or with different status
codes in different controllers.
The graphiti-rails gem uses RescueRegistry to facilitate better JSON:API error handling, since Rails' out-of-the-box behavior doesn't adhere to the JSON:API spec.
Example usages:
class MyController < ActionController::Base
class CustomStatusError < StandardError; end
class CustomTitleError < StandardError; end
class DetailExceptionError < StandardError; end
class DetailProcError < StandardError; end
class DetailStringError < StandardError; end
class MetaProcError < StandardError; end
class LogFalseError < StandardError; end
class CustomHandlerError < StandardError; end
class RailsError < StandardError; end
class SubclassedError < CustomStatusError; end
class CustomErrorHandler < RescueRegistry::ExceptionHandler
def self.default_status
302
end
def title
"Custom Title"
end
end
register_exception CustomStatusError, status: 401
register_exception CustomTitleError, title: "My Title"
register_exception DetailExceptionError, detail: :exception
register_exception DetailProcError, detail: -> (e) { e.class.name.upcase }
register_exception DetailStringError, detail: "Custom Detail"
register_exception MetaProcError, meta: -> (e) { { class_name: e.class.name.upcase } }
register_exception CustomHandlerError, handler: CustomErrorHandler
register_exception RailsError, status: 403, handler: RescueRegistry::RailsExceptionHandler
register_exception CustomStatusError, status: 422, code: :name_invalid
endAdd this line to your application's Gemfile:
gem 'rescue_registry'We'd love to have your help improving rescue_registry, send a PR!
The gem is available as open source under the terms of the MIT License.