# frozen_string_literal: true # since all the rescue from clauses are not caught by the application controller for matches # we need to handle certain exceptions here module Middleware class DiscoursePublicExceptions < ::ActionDispatch::PublicExceptions def initialize(path) super end def call(env) # this is so so gnarly # sometimes we leak out exceptions prior to creating a controller instance # this can happen if we have an exception in a route constraint in some cases # this code re-dispatches the exception to our application controller so we can # properly translate the exception to a page exception = env["action_dispatch.exception"] response = ActionDispatch::Response.new # Special handling for invalid params, in this case we can not re-dispatch # the Request object has a "broken" .params which can not be accessed exception = nil if Rack::QueryParser::InvalidParameterError === exception # We also can not dispatch bad requests as no proper params exception = nil if ActionController::BadRequest === exception if exception begin fake_controller = ApplicationController.new fake_controller.response = response fake_controller.request = request = ActionDispatch::Request.new(env) # We can not re-dispatch bad mime types begin request.format rescue Mime::Type::InvalidMimeType return [400, {}, ["Invalid MIME type"]] end if ApplicationController.rescue_with_handler(exception, object: fake_controller) body = response.body if String === body body = [body] end return [response.status, response.headers, body] end rescue => e Discourse.warn_exception(e, message: "Failed to handle exception in exception app middleware") end end super end end end