Merge pull request #2615 from mkllnk/2575-variant-on-hand-api

2575 variant on hand api

app/models/spree/variant_decorator.rb

@@ -1,5 +1,6 @@
 require 'open_food_network/enterprise_fee_calculator'
 require 'open_food_network/variant_and_line_item_naming'
+require 'open_food_network/variant_stock'
 require 'open_food_network/products_cache'
 
 Spree::Variant.class_eval do
@@ -9,6 +10,7 @@ Spree::Variant.class_eval do
   # removing the Spree method to prevent error.
   remove_method :options_text if instance_methods(false).include? :options_text
   include OpenFoodNetwork::VariantAndLineItemNaming
+  include OpenFoodNetwork::VariantStock
 
   has_many :exchange_variants
   has_many :exchanges, through: :exchange_variants

lib/open_food_network/variant_stock.rb

@@ -0,0 +1,80 @@
+require 'active_support/concern'
+
+# These methods were available in Spree 1, but were removed in Spree 2.
+# We would still like to use them. Therefore we use only a single stock location
+# (default stock location) and use it to track the `count_on_hand` value that
+# was previously a database column on variants.
+#
+# We may decide to deprecate these methods after we designed the Network feature.
+module OpenFoodNetwork
+  module VariantStock
+    extend ActiveSupport::Concern
+
+    included do
+      after_save :save_stock
+    end
+
+    def on_hand
+      if on_demand
+        Float::INFINITY
+      else
+        total_on_hand
+      end
+    end
+
+    def count_on_hand
+      total_on_hand
+    end
+
+    def on_hand=(new_level)
+      error = 'Cannot set on_hand value when Spree::Config[:track_inventory_levels] is false'
+      raise error unless Spree::Config.track_inventory_levels
+
+      self.count_on_hand = new_level
+    end
+
+    def count_on_hand=(new_level)
+      raise_error_if_no_stock_item_available
+      overwrite_stock_levels new_level
+    end
+
+    def on_demand
+      stock_items.any?(&:backorderable?)
+    end
+
+    def on_demand=(new_value)
+      raise_error_if_no_stock_item_available
+
+      # There should be only one at the default stock location.
+      stock_items.each do |item|
+        item.backorderable = new_value
+      end
+    end
+
+    private
+
+    def save_stock
+      stock_items.each(&:save)
+    end
+
+    def raise_error_if_no_stock_item_available
+      message = 'You need to save the variant to create a stock item before you can set stock levels.'
+      raise message if stock_items.empty?
+    end
+
+    # Backwards compatible setting of stock levels in Spree 2.0.
+    # It would be better to use `Spree::StockItem.adjust_count_on_hand` which
+    # takes a value to add to the current stock level and uses proper locking.
+    # But this should work the same as in Spree 1.3.
+    def overwrite_stock_levels(new_level)
+      stock_items.first.send :count_on_hand=, new_level
+
+      # There shouldn't be any other stock items, because we should have only one
+      # stock location. But in case there are, the total should be new_level,
+      # so all others need to be zero.
+      stock_items[1..-1].each do |item|
+        item.send :count_on_hand=, 0
+      end
+    end
+  end
+end

spec/controllers/spree/orders_controller_spec.rb

@@ -82,8 +82,8 @@ describe Spree::OrdersController, type: :controller do
     describe "generating stock levels" do
       let!(:order) { create(:order) }
       let!(:li) { create(:line_item, order: order, variant: v, quantity: 2, max_quantity: 3) }
-      let!(:v) { create(:variant, count_on_hand: 4) }
-      let!(:v2) { create(:variant, count_on_hand: 2) }
+      let!(:v) { create(:variant, on_hand: 4) }
+      let!(:v2) { create(:variant, on_hand: 2) }
 
       before do
         order.reload
@@ -107,7 +107,7 @@ describe Spree::OrdersController, type: :controller do
       end
 
       describe "encoding Infinity" do
-        let!(:v) { create(:variant, on_demand: true, count_on_hand: 0) }
+        let!(:v) { create(:variant, on_demand: true, on_hand: 0) }
 
         it "encodes Infinity as a large, finite integer" do
           controller.stock_levels(order, [v.id]).should ==

spec/factories.rb

@@ -459,7 +459,17 @@ FactoryBot.define do
   end
 
   factory :simple_product, parent: :base_product do
-    on_hand 5
+    transient do
+      on_demand { false }
+      on_hand { 5 }
+    end
+    after(:create) do |product, evaluator|
+      product.variants.first.tap do |variant|
+        variant.on_demand = evaluator.on_demand
+        variant.count_on_hand = evaluator.on_hand
+        variant.save
+      end
+    end
   end
 end
 
@@ -487,8 +497,19 @@ FactoryBot.modify do
   end
 
   factory :variant do
+    transient do
+      on_demand { false }
+      on_hand { 5 }
+    end
+
     unit_value 1
     unit_description ''
+
+    after(:create) do |variant, evaluator|
+      variant.on_demand = evaluator.on_demand
+      variant.count_on_hand = evaluator.on_hand
+      variant.save
+    end
   end
 
   factory :shipping_method do

spec/jobs/subscription_placement_job_spec.rb

@@ -64,9 +64,9 @@ describe SubscriptionPlacementJob do
     let(:shop) { order_cycle.coordinator }
     let(:order) { create(:order, order_cycle: order_cycle, distributor: shop) }
     let(:ex) { create(:exchange, :order_cycle => order_cycle, :sender => shop, :receiver => shop, :incoming => false) }
-    let(:variant1) { create(:variant, count_on_hand: 5) }
-    let(:variant2) { create(:variant, count_on_hand: 5) }
-    let(:variant3) { create(:variant, count_on_hand: 5) }
+    let(:variant1) { create(:variant, on_hand: 5) }
+    let(:variant2) { create(:variant, on_hand: 5) }
+    let(:variant3) { create(:variant, on_hand: 5) }
     let!(:line_item1) { create(:line_item, order: order, variant: variant1, quantity: 3) }
     let!(:line_item2) { create(:line_item, order: order, variant: variant2, quantity: 3) }
     let!(:line_item3) { create(:line_item, order: order, variant: variant3, quantity: 3) }

spec/lib/open_food_network/lettuce_share_report_spec.rb

@@ -36,7 +36,7 @@ module OpenFoodNetwork
       describe "lists" do
         let(:v2) { create(:variant) }
         let(:v3) { create(:variant) }
-        let(:v4) { create(:variant, count_on_hand: 0, on_demand: true) }
+        let(:v4) { create(:variant, on_hand: 0, on_demand: true) }
         let(:hub_address) { create(:address, :address1 => "distributor address", :city => 'The Shire', :zipcode => "1234") }
         let(:hub) { create(:distributor_enterprise, :address => hub_address) }
         let(:v2o) { create(:variant_override, hub: hub, variant: v2) }

spec/lib/open_food_network/scope_variant_to_hub_spec.rb

@@ -3,7 +3,7 @@ require 'open_food_network/scope_variant_to_hub'
 module OpenFoodNetwork
   describe ScopeVariantToHub do
     let(:hub) { create(:distributor_enterprise) }
-    let(:v)   { create(:variant, price: 11.11, count_on_hand: 1, on_demand: true, sku: "VARIANTSKU") }
+    let(:v)   { create(:variant, price: 11.11, on_hand: 1, on_demand: true, sku: "VARIANTSKU") }
     let(:vo)  { create(:variant_override, hub: hub, variant: v, price: 22.22, count_on_hand: 2, on_demand: false, sku: "VOSKU") }
     let(:vo_price_only) { create(:variant_override, hub: hub, variant: v, price: 22.22, count_on_hand: nil) }
     let(:scoper) { ScopeVariantToHub.new(hub) }

spec/models/variant_override_spec.rb

@@ -59,7 +59,7 @@ describe VariantOverride do
 
   describe "looking up count on hand" do
     it "returns the numeric stock level when present" do
-      VariantOverride.create!(variant: variant, hub: hub, count_on_hand: 12)
+      VariantOverride.create!(variant: variant, hub: hub, on_hand: 12)
       VariantOverride.count_on_hand_for(hub, variant).should == 12
     end
 

spec/services/subscription_form_spec.rb

@@ -7,7 +7,7 @@ describe SubscriptionForm do
     let!(:product3) { create(:product, supplier: shop) }
     let!(:variant1) { create(:variant, product: product1, unit_value: '100', price: 12.00, option_values: []) }
     let!(:variant2) { create(:variant, product: product2, unit_value: '1000', price: 6.00, option_values: []) }
-    let!(:variant3) { create(:variant, product: product2, unit_value: '1000', price: 2.50, option_values: [], count_on_hand: 1) }
+    let!(:variant3) { create(:variant, product: product2, unit_value: '1000', price: 2.50, option_values: [], on_hand: 1) }
     let!(:enterprise_fee) { create(:enterprise_fee, amount: 1.75) }
     let!(:order_cycle1) { create(:simple_order_cycle, coordinator: shop, orders_open_at: 9.days.ago, orders_close_at: 2.days.ago) }
     let!(:order_cycle2) { create(:simple_order_cycle, coordinator: shop, orders_open_at: 2.days.ago, orders_close_at: 5.days.from_now) }