This gem is unmaintained.

Monitors changes to has_many and has_and_belongs_to_many associations using ActiveModel::Dirty.

Include DirtyAssociations concern in your model.

include DirtyAssociations

Call monitor_association_changes method after has_many.

has_many :foos
monitor_association_changes :foos

Check one of the following methods to see if the relation has changed:

• changes

• changed

• previous_changes

• [singularized_association_name]_ids_changed?

• [singularized_association_name]_ids_previously_changed?

  bar.foos = [ Foo.find(42) ] # or you can use the foo_ids setter
  bar.changes # { "foo_ids" => [[5], [42]] }
  bar.changed # [ "foo_ids" ]
  bar.foo_ids_changed? # true
  bar.foo_ids_previously_changed? # false
  
  bar.save
  bar.previous_changes # { "foo_ids" => [[5], [42]] }
  bar.foo_ids_changed? # false
  bar.foo_ids_previously_changed? # true