null_logger

Null Logger

It's nice to be able to inject a Logger into libraries to see what's going on, but handling all that logging and providing sane defaults can be rather difficult.

If we use a Null Logger - a logger which does nothing but which supports the Logger interface - we can pass that responsibility off to those who care about logging.

Usage

In your Gemfile:

gem 'null_logger'

In your code you can use the NullLogger instance just like a real Logger:

require 'null_logger'
logger = NullLogger.instance
logger.debug "Foo"
logger.info  "Bar"
logger.warn  "Baz"
logger.error "Qux"
logger.fatal "Quux"

Of course, you'll probably want to allow people the option to pass in a logger, otherwise there's not much point, so your classes end up looking something like this:

class Groml
  attr_accessor :logger
  private :logger=, :logger

  def initialize logger = nil
    self.logger = logger || NullLogger.instance
  end

  def execute
    logger.debug "Starting execute run..."
  end
end

Authors

Craig R Webster http://barkingiguana.com/