Adding data migration to populate inventories of enterprises that are already using variant overrides

app/models/inventory_item.rb

@@ -1,5 +1,5 @@
 class InventoryItem < ActiveRecord::Base
-  attr_accessible :enterprise_id, :variant_id, :visible
+  attr_accessible :enterprise, :enterprise_id, :variant, :variant_id, :visible
 
   belongs_to :enterprise
   belongs_to :variant, class_name: "Spree::Variant"

db/migrate/20160218235221_populate_inventories.rb

@@ -0,0 +1,22 @@
+class PopulateInventories < ActiveRecord::Migration
+  def up
+    # If hubs are actively using overrides, populate their inventories with all variants they have permission to override
+    # Otherwise leave their inventories empty
+
+    hubs_using_overrides = Enterprise.joins("LEFT OUTER JOIN variant_overrides ON variant_overrides.hub_id = enterprises.id")
+      .where("variant_overrides.id IS NOT NULL").select("DISTINCT enterprises.*")
+
+    hubs_using_overrides.each do |hub|
+      overridable_producers = OpenFoodNetwork::Permissions.new(hub.owner).variant_override_producers
+
+      variants = Spree::Variant.where(is_master: false, product_id: Spree::Product.not_deleted.where(supplier_id: overridable_producers))
+
+      variants.each do |variant|
+        InventoryItem.create(enterprise: hub, variant: variant, visible: true)
+      end
+    end
+  end
+
+  def down
+  end
+end

db/schema.rb

@@ -11,7 +11,7 @@
 #
 # It's strongly recommended to check this file into your version control system.
 
-ActiveRecord::Schema.define(:version => 20160204031816) do
+ActiveRecord::Schema.define(:version => 20160218235221) do
 
   create_table "account_invoices", :force => true do |t|
     t.integer  "user_id",    :null => false