discourse/lib/middleware/discourse_public_exceptions.rb

76 lines
2.3 KiB
Ruby

# 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
INVALID_REQUEST_ERRORS =
Set.new(
[
Rack::QueryParser::InvalidParameterError,
ActionController::BadRequest,
ActionDispatch::Http::Parameters::ParseError,
],
)
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
exception = nil if INVALID_REQUEST_ERRORS.include?(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,
{ "Cache-Control" => "private, max-age=0, must-revalidate" },
["Invalid MIME type"]
]
end
# Or badly formatted multipart requests
begin
request.POST
rescue EOFError
return [
400,
{ "Cache-Control" => "private, max-age=0, must-revalidate" },
["Invalid request"]
]
end
if ApplicationController.rescue_with_handler(exception, object: fake_controller)
body = response.body
body = [body] if String === body
return response.status, response.headers, body
end
rescue => e
return super if INVALID_REQUEST_ERRORS.include?(e.class)
Discourse.warn_exception(
e,
message: "Failed to handle exception in exception app middleware",
)
end
end
super
end
end
end