This gem provides syslog-style logging for rails applications.

Standard rails log:

Completed 200 OK in 103ms (Views: 83.7ms | ActiveRecord: 0.0ms)

With logjam_formatter, including optional user_id:

Dec 18 17:36:17 elk rails[13902]: INFO user[10]: Completed 200 OK in 103ms (Views: 83.7ms | ActiveRecord: 0.0ms)

Installation

Gemfile:

gem 'logjam_formatter'

application.rb:

config.logger.formatter = Logjam::Formatter.new

User ids

User ids can be logged via a global hash, $user_ids. You can use a before_filter in your application_controller to set it, eg:

before_filter { |controller| ($user_ids ||= {})[Thread.current] = controller.session[:user_id] || 0 }

This is optional -- if $user_ids is undefined, that part of the log line will be left out.

Log file analysis

Logjam::Formatter was written to work well with Logjam.