StrftimeLogger

A logger treats log rotation in strftime fashion.

What is this for?

The ruby's built-in logger does log rotation in the basis of log size. In contrast, StrftimeLogger provides a feature to rotate logs in the basis of time.

This logger allows to specify the log path with strftime format such as:

logger = StrftimeLogger.new('/var/log/application.log.%Y%m%d')

which enables to rotate logs in each specific time.

In fact, this logger does not rotate logs, but outputs to the strftime formatted path directly.

This characteristic gives a side effect that it does not require to lock files in log rotation.

Installation

Add this line to your application's Gemfile:

gem 'strftime_logger'

And then execute:

$ bundle

How to use

Normal Usage

require 'strftime_logger'
logger = StrftimeLogger.new('/var/log/application.log.%Y%m%d')
logger.info("foo\nbar")

which outputs logs to /var/log/application.log.YYYYMMDD with contents like

20140630T00:00:00+09:00 [INFO] foo\\nbar

where the time is in ISO8601 format, and the line feed characters \n in log messages are replaced with \\n so that the log message will be in one line.

Change the log level

logger.level = StrftimeLogger::WARN

Or, short-hand: 

logger.log_level = 'WARN'

Change the Formatter

It is possible to change the logger formmater as:

logger.formatter = SampleFormatter.new

The interface which the costom formmatter must provide is only #initialize(opts = {}) and #call(sevirity, message = nil, &block). Following is a simple example:

class SampleFormatter
  LEVEL_TEXT = %w(DEBUG INFO WARN ERROR FATAL UNKNOWN)

  def initialize(opts={})
  end

  # @param sevirity [int] log sevirity
  def call(severity, message = nil, &block)
    if message.nil?
      if block_given?
        message = yield
      else
        message = ""
      end
    end
    "#{Time.now} #{LEVEL_TEXT[sevirity]} #{message}"
  end
end

ToDo

  • Support datetime_format

ChangeLog

See CHANGELOG.md for details.

Contributing

  1. Fork it
  2. Create your feature branch (git checkout -b my-new-feature)
  3. Commit your changes (git commit -am 'Add some feature')
  4. Push to the branch (git push origin my-new-feature)
  5. Create new Pull Request

See LICENSE.txt for details.