Use ProductCatalog instead of Product to retrieve stock

rails_application/app/controllers/orders_controller.rb

@@ -73,16 +73,16 @@ def reset_discount
   end
 
   def add_item
-    product = Product.find(params[:product_id])
-    if product.stock_level < 1
+    product_catalog = Inventory::ProductCatalog.find_by(product_id: params[:product_id])
+    if product_catalog.stock_level < 1
       redirect_to edit_order_path(params[:id]),
                   alert: "Product not available in requested quantity!" and return
     end
 
     @order = Order.find(params[:id])
     ApplicationRecord.transaction do
       @order.add_item(Product.find(params[:product_id]))
-      Inventory::ProductService.new.decrement_stock_level(Inventory::DecreaseStockLevel.new(product_id: product.id))
+      Inventory::ProductService.new.decrement_stock_level(Inventory::DecreaseStockLevel.new(product_id: product_catalog.product_id))
       @order.save!
       event_store.publish(Ordering::ItemAdded.new(data: { order_id: @order.id, product_id: params[:product_id] }), stream_name: "Ordering::Order$#{@order.id}")
     end

rails_application/test/integration/orders_test.rb

@@ -37,7 +37,7 @@ def test_happy_path
 
     assert_remove_buttons_not_visible(async_remote_id, fearless_id)
 
-    assert_changes -> { Product.find(async_remote_id).stock_level }, from: 10, to: 9 do
+    assert_changes -> { Inventory::ProductCatalog.find_by(product_id: async_remote_id).stock_level }, from: 10, to: 9 do
       post "/orders/#{order_id}/add_item?product_id=#{async_remote_id}"
     end
     assert_expected_events_in_stream(
@@ -48,7 +48,7 @@ def test_happy_path
       ]
     )
 
-    assert_changes -> { Product.find(fearless_id).stock_level }, from: 10, to: 8 do
+    assert_changes -> { Inventory::ProductCatalog.find_by(product_id: fearless_id).stock_level }, from: 10, to: 8 do
       post "/orders/#{order_id}/add_item?product_id=#{fearless_id}"
       post "/orders/#{order_id}/add_item?product_id=#{fearless_id}"
       post "/orders/#{order_id}/remove_item?product_id=#{fearless_id}"
@@ -100,7 +100,7 @@ def test_expiring_orders
     get "/orders"
     assert_select("td", "Draft")
 
-    assert_changes -> { Product.find(async_remote_id).stock_level }, from: 9, to: 10 do
+    assert_changes -> { Inventory::ProductCatalog.find_by(product_id: async_remote_id).stock_level }, from: 9, to: 10 do
       post "/orders/expire"
     end
 

rails_application/test/integration/supplies_test.rb

@@ -15,15 +15,16 @@ def test_supply_new_product
     assert_select "tr#product_#{product.id}" do
       assert_select "td", "10"
     end
-    assert_equal(10, product.reload.stock_level)
+    product_catalog = Inventory::ProductCatalog.find_by(product_id: product.id)
+    assert_equal(10, product_catalog.stock_level)
   end
 
   def test_supply_product_with_existing_stock
     create_product
     product = Product.find_by(sku:)
     increase_stock_level_by_10(product.id)
 
-    assert_changes -> { Product.find(product.id).stock_level }, from: 10, to: 20 do
+    assert_changes -> { Inventory::ProductCatalog.find_by(product_id: product.id).stock_level }, from: 10, to: 20 do
       increase_stock_level_by_10(product.id)
     end