stable, before a refactor

app/models/card_exception.rb

@@ -0,0 +1,10 @@
+class CardException < ApplicationRecord
+    belongs_to :employer
+    has_many :card_exception_items
+    accepts_nested_attributes_for :card_exception_items, allow_destroy: true, reject_if: :all_blank
+
+    VALID_TYPES = ['zipcode', 'state', 'family_id']
+
+    validates :type, inclusion: { in: VALID_TYPES,
+                                    message: "%{value} is not a valid exception type" }
+end