---
layout: post
title: "Colorful logging in Rails 3.2"
date: 2013-03-17 17:54
comments: true
categories: [rails]
cover: /images/cover/avatar.png
keywords: ruby on rails, ruby, rails, logger, formatting, colors
description: Formate and colorize log output in Rails
---

The default Rails logger is really messy. Write somewhere ```logger.debug
some_object.inspect``` and then for an hour search where the goddamn message is
in a log file. Fortunately we can format and colorize ```logger``` output.

Create ```config/initializers/log_formatting.rb``` file and paste this code:

{% codeblock lang:ruby %}{% raw %}
class ActiveSupport::BufferedLogger
    def formatter=(formatter)
        @log.formatter = formatter
    end
end

class Formatter
    SEVERITY_TO_COLOR_MAP   = {'DEBUG'=>'33', 'INFO'=>'0;37', 'WARN'=>'36', 'ERROR'=>'31', 'FATAL'=>'31', 'UNKNOWN'=>'37'}

    def call(severity, time, progname, msg)
        formatted_severity = sprintf("%s","#{severity}")

        formatted_time = time.strftime("%Y-%m-%d %H:%M:%S.") << time.usec.to_s[0..2].rjust(3)
        color = SEVERITY_TO_COLOR_MAP[severity]

        if msg.empty?
            "\n"
        else
            "\033[0;37m#{formatted_time}\033[0m [#{formatted_severity}] \033[#{color}m#{msg.strip}\033[0m\n"
        end
    end

end

Rails.logger.formatter = Formatter.new
{% endraw %}{% endcodeblock %}

I found original code
[here](http://cbpowell.wordpress.com/2012/04/05/beautiful-logging-for-ruby-on-rails-3-2/).
I've just made small changes -- adjusted colors and formatting (and removed humorous
stuff).

This is how it looks in ```tail -f log/development.log```:
{% img /images/rails-logger.png %}