Sawmill is a logging and log analysis system for Ruby. It extends the basic Ruby logging facility with log records and logfile parsing features.

A user reported a bug in your Rails application, and now you have to figure out what happened. You can spend hours poring over megabytes of text log files, stretching your grep-fu to its snapping point… or you can use Sawmill.

Your CEO wants to know how many people viewed the new product pages last week. You can write yet another arcane sed script looking for that elusive pattern in the log files… or you can use Sawmill.

Sawmill is an extension to the standard ruby Logger mechanism that enables automated log analysis. Designed especially for web applications using Ruby on Rails and similar frameworks, Sawmill originated in the source to www.geopage.com, where it has been analyzing the production Rails logs for more than three years.

• Drop-in compatible with standard ruby Logger class

• Custom log levels

• Process log entries as objects

• Group log entries into log records with unique record IDs and attributes

• Filtering and analysis of log entries and log records

• Write logfiles, optionally with one of several logfile rotation mechanisms

• Parse logfiles back into log entries and log records

• Log analysis framework

• Rack middleware for quick setup of web service logs

• Railtie for Rails 3 integration

• Ruby 1.8.7 or later (Ruby 1.9.2 or later recommended), or JRuby 1.4 or later.

• Blockenspiel 0.4.5 or later.

gem install sawmill

Sawmill is currently under development, and some features are not yet complete or fully tested.

Documentation is available at dazuma.github.com/sawmill/rdoc

Source code is hosted on Github at github.com/dazuma/sawmill

Contributions are welcome. Fork the project on Github.

Build status: <img src=“https://secure.travis-ci.org/dazuma/sawmill.png” />

Report bugs on Github issues at github.org/dazuma/sawmill/issues

Contact the author at dazuma at gmail dot com.

Sawmill is written by Daniel Azuma (www.daniel-azuma.com).

Development is supported by Pirq (www.pirq.com).

Continuous integration service provided by Travis-CI (travis-ci.org).

Copyright 2009-2012 Daniel Azuma.

All rights reserved.

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

• Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.

• Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.

• Neither the name of the copyright holder, nor the names of any other contributors to this software, may be used to endorse or promote products derived from this software without specific prior written permission.

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