Feature: Raising an exception in case of a non-successful response

[Marc Köhlbrugge]

Unlike many other gems, HTTP doesn't raise an exception when the response is unsuccessful due to a client side or server side error such as 404 (Not Found), or 500 (Server Error).

I needed this functionality in some situations, so I made the following feature:

module HTTP
  class BadRequestError < Error; end
  class UnauthorizedError < Error; end
  class ForbiddenError < Error; end
  class ResourceNotFoundError < Error; end
  class ClientError < Error; end
  class ServerError < Error; end


  module Features
    class Exceptions < Feature
      def wrap_response(response)
        case response.status.code
        when 401
          raise UnauthorizedError, response.status
        when 403
          raise ForbiddenError, response.status
        when 404
          raise ResourceNotFound, response.status
        when 400..499
          raise ClientError, response.status
        when 500..599
          raise ServerError, response.status
        end


        response
      end


      HTTP::Options.register_feature(:exceptions, self)
    end
  end
end

It can be used as such:

begin
  HTTP.use(:exceptions).get("https://google.com/does-not-exist")
rescue HTTP::ResourceNotFound
  # 404
rescue HTTP::Error
  # Something else
end

If the maintainers of the gem are interested, I'd be happy to create PR adding this to the gem. Alternatively, I can create a separate `http-features-exceptions` gem if there's enough interest in the community for such a thing.

Credit for the case statement goes to my colleague Jankees van Woezik.