Hi Mongoid community, when a Mongoid object is updated( e.g. save operation), is there an easy way to track(via code) all other Mongoid objects that might be accessed?

[d2army]

Hi there Mongoid Community team,

We are doing an internal audit of our Mongoid models and want to understand just how coupled they are to one another ( e.g. callbacks that hit other models, validations that check other models, etc)

When a Mongoid object is updated( e.g. save operation), is there an efficient way to track(via code) all other Mongoid objects that might be accessed? I am open to all options( static checking, runtime, etc)

Thanks

[jamis]

Hey @d2army, there's not really a built-in way to do this, but here's a quick-and-dirty proof-of-concept I threw together. Maybe it'll give you some ideas?

module SaveTracking
  extend ActiveSupport::Concern

  class <<self
    def apply!
      Mongoid.models.each { |klass| klass.include(SaveTracking) }
      reset!
    end

    def reset!
      @touched_classes_map = nil
    end

    def touched_classes_map
      @touched_classes_map ||= Hash.new(0)
    end

    def track_save!(model)
      touched_classes_map[model.class] += 1
    end

    def around
      reset!
      yield
      touched_classes_map
    end
  end

  included do
    before_save { SaveTracking.track_save!(self) }
  end
end

class Foo
  include Mongoid::Document

  before_save { bars << Bar.new }
  has_many :bars
end

class Bar
  include Mongoid::Document
  belongs_to :foo
end

SaveTracking.apply!

result = SaveTracking.around do
  Foo.create!
end

p result