Add payment method fees to order during checkout

The fee is displayed as "Transaction fee".

app/assets/javascripts/darkswarm/services/checkout.js.coffee

@@ -62,8 +62,11 @@ Darkswarm.factory 'Checkout', (CurrentOrder, ShippingMethods, PaymentMethods, $h
     shippingPrice: ->
       @shippingMethod()?.price || 0.0
 
+    paymentPrice: ->
+      @paymentMethod()?.price || 0.0
+
     paymentMethod: ->
       PaymentMethods.payment_methods_by_id[@order.payment_method_id]
 
     cartTotal: ->
-      @shippingPrice() + @order.display_total
+      @order.display_total + @shippingPrice() + @paymentPrice()

app/assets/javascripts/darkswarm/services/payment_methods.js.coffee

@@ -4,5 +4,6 @@ Darkswarm.factory "PaymentMethods", (paymentMethods)->
     payment_methods_by_id: {}
     constructor: ->
       for method in @payment_methods
+        method.price = parseFloat(method.price)
         @payment_methods_by_id[method.id] = method
 

app/helpers/checkout_helper.rb

@@ -94,4 +94,13 @@ module CheckoutHelper
     current_order.tokenized_permission.save!
     session[:access_token] = token
   end
+
+  def payment_method_price(method, order)
+    price = method.compute_amount(order)
+    if price == 0
+      t('checkout_method_free')
+    else
+      "{{ #{price} | localizeCurrency }}"
+    end
+  end
 end

app/models/spree/payment_decorator.rb

@@ -1,5 +1,24 @@
 module Spree
   Payment.class_eval do
+    has_one :adjustment, as: :source, dependent: :destroy
+
+    after_save :ensure_correct_adjustment, :update_order
+
+    def ensure_correct_adjustment
+      if adjustment
+        adjustment.originator = payment_method
+        adjustment.label = adjustment_label
+        adjustment.save
+      else
+        payment_method.create_adjustment(adjustment_label, order, self, true)
+        reload
+      end
+    end
+
+    def adjustment_label
+      I18n.t('payment_method_fee')
+    end
+
     # Pin payments lacks void and credit methods, but it does have refund
     # Here we swap credit out for refund and remove void as a possible action
     def actions_with_pin_payment_adaptations

app/serializers/api/payment_method_serializer.rb

@@ -1,3 +1,8 @@
 class Api::PaymentMethodSerializer < ActiveModel::Serializer
-  attributes :name, :description, :id, :method_type
+  attributes :name, :description, :id, :method_type,
+             :price
+
+  def price
+    object.compute_amount(options[:current_order])
+  end
 end

app/views/checkout/_payment.html.haml

@@ -26,6 +26,7 @@
                     name: "order.payment_method_id",
                     "ng-model" => "order.payment_method_id"
                   = method.name
+                  = "(#{payment_method_price(method, @order)})"
 
                 %small.error.medium.input-text{"ng-show" => "!fieldValid('order.payment_method_id')"}
                   = "{{ fieldErrors('order.payment_method_id') }}"

app/views/checkout/_summary.html.haml

@@ -19,6 +19,11 @@
             = t :checkout_shipping_price
           %td.shipping.text-right {{ Checkout.shippingPrice() | localizeCurrency }}
 
+        %tr
+          %th
+            = t :payment_method_fee
+          %td.text-right {{ Checkout.paymentPrice() | localizeCurrency }}
+
         %tr
           %th
             = t :checkout_total_price

config/locales/en.yml

@@ -1038,6 +1038,7 @@ Please follow the instructions there to make your enterprise visible on the Open
   properties: "Properties"
   shipping_methods: "Shipping Methods"
   payment_methods: "Payment Methods"
+  payment_method_fee: "Transaction fee"
   enterprise_fees: "Enterprise Fees"
   inventory_settings: "Inventory Settings"
   tag_rules: "Tag Rules"

spec/features/admin/adjustments_spec.rb

@@ -48,7 +48,7 @@ feature %q{
     visit spree.admin_orders_path
     page.find('td.actions a.icon-edit').click
     click_link 'Adjustments'
-    page.find('td.actions a.icon-edit').click
+    page.find('tr', text: 'Shipping').find('a.icon-edit').click
 
     # Then I should see the uneditable included tax and our tax rate as the default
     page.should have_field :adjustment_included_tax, with: '10.00', disabled: true
@@ -72,7 +72,7 @@ feature %q{
     visit spree.admin_orders_path
     page.find('td.actions a.icon-edit').click
     click_link 'Adjustments'
-    page.find('td.actions a.icon-edit').click
+    page.find('tr', text: 'Shipping').find('a.icon-edit').click
 
     # Then I should see the uneditable included tax and 'Remove tax' as the default tax rate
     page.should have_field :adjustment_included_tax, with: '0.00', disabled: true