Include DFC Offer in the export with valid id

engines/dfc_provider/app/controllers/dfc_provider/catalog_items_controller.rb

@@ -15,8 +15,9 @@ module DfcProvider
     end
 
     def show
-      dfc_object = DfcBuilder.catalog_item(variant)
-      render json: DfcLoader.connector.export(dfc_object)
+      catalog_item = DfcBuilder.catalog_item(variant)
+      offers = catalog_item.offers
+      render json: DfcLoader.connector.export(catalog_item, *offers)
     end
 
     private

engines/dfc_provider/app/services/dfc_builder.rb

@@ -27,7 +27,11 @@ class DfcBuilder
   end
 
   def self.offer(variant)
-    id = "/offers/#{variant.id}"
+    # We don't have an endpoint for offers yet and this URL is only a
+    # placeholder for now. The offer is actually affected by order cycle and
+    # customer tags. We'll solve that at a later stage.
+    enterprise_url = urls.enterprise_url(id: variant.product.supplier_id)
+    id = "#{enterprise_url}/offers/#{variant.id}"
     offered_to = []
 
     # The DFC sees "empty" stock as unlimited.