Gists for this blog post: http://inside.oib.com/getting-more-information-from-omniauth-exceptions/

oib_new_proc.rb

OmniAuth.config.on_failure do |env|
  exception = env['omniauth.error']
  error_type = env['omniauth.error.type']
  strategy = env['omniauth.error.strategy']

  Rails.logger.error("OmniAuth Error (#{error_type}): #{exception.inspect}")
  ErrorNotifier.exception(exception, :strategy => strategy.inspect, :error_type => error_type)

  new_path = "#{env['SCRIPT_NAME']}#{OmniAuth.config.path_prefix}/failure?message=#{error_type}"

  [302, {'Location' => new_path, 'Content-Type'=> 'text/html'}, []]
end

omniauth_default_proc.rb

Proc.new do |env|
  message_key = env['omniauth.error.type']
  new_path = "#{env['SCRIPT_NAME']}#{OmniAuth.config.path_prefix}/failure?message=#{message_key}"
  [302, {'Location' => new_path, 'Content-Type'=> 'text/html'}, []]
end