Gem's initialization advise

initialization advise

I'm creating a Gem but I'm struggling to decide it's initialization.

I have 2 options:

1. Require the user to manually initialize the Gem:

Module MyGem
  def self.init
    @my_var = db_resource
  end
  def self.do_action
    puts @my_var
  end
end

2. Include the initialization in the only method of the Gem. We can
safely assume that the any app will call the Gem's method in O(n).

Module MyGem
  def self.do_action
    @my_var ||= db_resource
    puts @my_var
  end
end

So WDYT?