From my recent pull request on Airbrake:

We recently noticed that Airbrake doesn’t always filter our parameters.

I looked into the cases, and eventually narrowed it down to this: an unhandled exception is filtered properly, but a notification made via notify_airbrake does not.

I traced the problem to


def airbrake_filter_if_filtering(hash)
  return hash if ! hash.is_a?(Hash)

  if respond_to?(:filter_parameters)
    filter_parameters(hash) rescue hash

After doing some research, I found that filter_parameters is a Rails 2 method that has since been replaced by ActionDispatch::Http::ParameterFilter. There are other methods used in Airbrake are deprecated by Rails. For example filter_parameter_logging (found in test/catcher_test.rb) disappeared after Rails 2.3.8.

I attempted to add a test for my changes, but couldn’t reproduce the problem using the available helpers in test/catcher_test.rb, although the problem clearly exists in our production use. As near as I can tell process_action_with_manual_notification may not actually be testing in a realistic way; there seem to be at least two ways that Airbrake filters parameters. If I’m missing something, please point me in the right direction.

At any rate, the changes in this pull request fixes the problem when I tested on a staging environment. Our app is using Ruby 1.9.2p180 and Rails 3.1.2 at the time of this writing.