How to write log inside my rubygem that will be used in a rails app?

Question

I'm developing a rubygem that will be used in a rails app. In this rubygem i need to log some information (warnings, errors...).

I saw some gems to do this, like logging, but apparently i need no configure the log output (stdout, some file).
My rails app log the messages in a file. So, my question: Is there a way to my gem use the same log configuration that my rails app uses? or my gem will send the log according to his own configuration?

Answer 1

You may use Rails.logger directly, which is valid if your gem will always only be used within a Rails application. You may alternatively define a logger for your gem namespace and default to Rails.logger if defined, or Logger.new(STDOUT) if it's not, along with a writer, so it's overridable:

module MyGem
  def self.logger
    @@logger ||= defined?(Rails) ? Rails.logger : Logger.new(STDOUT)
  end

  def self.logger=(logger)
    @@logger = logger
  end
end

Whatever the case, you will use it like this:

MyGem.logger.debug "it works"