Extract query object

app/controllers/admin/customers_controller.rb

@@ -65,13 +65,7 @@ def destroy
     def collection
       return Customer.where("1=0") unless json_request? && params[:enterprise_id].present?
 
-      Customer.of(managed_enterprise_id).
-        includes(:bill_address, :ship_address, user: :credit_cards).
-        joins(:orders).
-        merge(Spree::Order.complete.not_state(:canceled)).
-        group("customers.id").
-        select("customers.*").
-        select("SUM(total - payment_total) AS balance_value")
+      CustomersWithBalance.new(managed_enterprise_id).query
     end
 
     def managed_enterprise_id

app/services/customers_with_balance.rb

@@ -0,0 +1,19 @@
+class CustomersWithBalance
+  def initialize(enterprise_id)
+    @enterprise_id = enterprise_id
+  end
+
+  def query
+    Customer.of(enterprise_id).
+      includes(:bill_address, :ship_address, user: :credit_cards).
+      joins(:orders).
+      merge(Spree::Order.complete.not_state(:canceled)).
+      group("customers.id").
+      select("customers.*").
+      select("SUM(total - payment_total) AS balance_value")
+  end
+
+  private
+
+  attr_reader :enterprise_id
+end