custom primary key for transaction

app/models/customer.rb

@@ -1,4 +1,5 @@
 class Customer < ApplicationRecord
+  before_create :generate_custom_id
   has_many :orders
   has_many :sales
 
@@ -8,4 +9,9 @@ class Customer < ApplicationRecord
   def lastest_invoices
     sales.where(:customer_id => self.id).order("created_at desc").limit(5)
   end
+
+  private
+  def generate_custom_id
+    self.customer_id = SeedGenerator.generate_id(self.class.name, "CUS")
+  end
 end