Import variants for the same product group

When importing another catalog, it's probably referring to external
product groups. Storing the external link allows us to group several
variants and replicate the same structure within OFN.

app/models/spree/product.rb

@@ -36,6 +36,7 @@ module Spree
     searchable_scopes :active, :with_properties
 
     has_one :image, class_name: "Spree::Image", as: :viewable, dependent: :destroy
+    has_one :semantic_link, as: :subject, dependent: :delete
 
     has_many :product_properties, dependent: :destroy
     has_many :properties, through: :product_properties

engines/dfc_provider/app/services/supplied_product_importer.rb

@@ -44,6 +44,7 @@ class SuppliedProductImporter < DfcBuilder
   # We will remove the old methods at some point.
   def self.referenced_spree_product(supplied_product, supplier)
     spree_product(supplied_product, supplier) ||
+      spree_product_linked(supplied_product, supplier) ||
       spree_product_from_uri(supplied_product, supplier) ||
       spree_product_from_id(supplied_product, supplier)
   end
@@ -51,15 +52,28 @@ class SuppliedProductImporter < DfcBuilder
   def self.spree_product(supplied_product, supplier)
     supplied_product.isVariantOf.lazy.map do |group|
       group_id = group.semanticId
-      route = Rails.application.routes.recognize_path(group_id)
+      id = begin
+        route = Rails.application.routes.recognize_path(group_id)
 
-      # Check that the given URI points to us:
-      next if group_id != urls.enterprise_technical_product_url(route)
+        # Check that the given URI points to us:
+        next if group_id != urls.enterprise_technical_product_url(route)
 
-      supplier.supplied_products.find_by(id: route[:id])
+        route[:id]
+      rescue ActionController::RoutingError
+        next
+      end
+
+      supplier.supplied_products.find_by(id:)
     end.compact.first
   end
 
+  def self.spree_product_linked(supplied_product, supplier)
+    semantic_ids = supplied_product.isVariantOf.map(&:semanticId)
+    supplier.supplied_products.includes(:semantic_link)
+      .where(semantic_link: { semantic_id: semantic_ids })
+      .first
+  end
+
   def self.spree_product_from_uri(supplied_product, supplier)
     uri = supplied_product.spree_product_uri
     return if uri.blank?
@@ -86,6 +100,7 @@ class SuppliedProductImporter < DfcBuilder
       supplier_id: supplier.id,
       primary_taxon_id: taxon(supplied_product).id,
       image: ImageBuilder.import(supplied_product.image),
+      semantic_link: semantic_link(supplied_product),
     ).tap do |product|
       QuantitativeValueBuilder.apply(supplied_product.quantity, product)
       product.ensure_standard_variant
@@ -105,9 +120,14 @@ class SuppliedProductImporter < DfcBuilder
     OfferBuilder.apply(offer, variant)
   end
 
+  def self.semantic_link(supplied_product)
+    semantic_id = supplied_product.isVariantOf.first&.semanticId
+
+    SemanticLink.new(semantic_id:) if semantic_id.present?
+  end
+
   def self.taxon(supplied_product)
     ProductTypeImporter.taxon(supplied_product.productType)
   end
-
   private_class_method :taxon
 end

engines/dfc_provider/spec/services/supplied_product_importer_spec.rb

@@ -186,7 +186,7 @@ RSpec.describe SuppliedProductImporter do
       expect(imported_variant.on_hand).to eq 0
     end
 
-    context "with spree_product_id supplied" do
+    context "linked to product group" do
       let(:imported_variant) { importer.import_variant(supplied_product, supplier) }
 
       let(:supplied_product) do
@@ -229,7 +229,13 @@ RSpec.describe SuppliedProductImporter do
               value: 2,
             ),
             productType: product_type,
-            spree_product_uri: "http://another.host/api/dfc/enterprises/10/supplied_products/50"
+            spree_product_uri: "http://another.host/api/dfc/enterprises/10/supplied_products/50",
+            isVariantOf: [technical_product],
+          )
+        end
+        let(:technical_product) do
+          DataFoodConsortium::Connector::TechnicalProduct.new(
+            "http://test.host/api/dfc/enterprises/7/technical_products/6"
           )
         end
 
@@ -243,6 +249,8 @@ RSpec.describe SuppliedProductImporter do
           expect(imported_product.name).to eq("Tomato")
           expect(imported_product.description).to eq("Awesome tomato")
           expect(imported_product.variant_unit).to eq("weight")
+          expect(imported_product.semantic_link.semantic_id)
+            .to eq "http://test.host/api/dfc/enterprises/7/technical_products/6"
         end
       end
     end
@@ -270,6 +278,19 @@ RSpec.describe SuppliedProductImporter do
       expect(result).to eq spree_product
     end
 
+    it "returns a product referenced by external URI" do
+      variant.save!
+      supplied_product.isVariantOf <<
+        DataFoodConsortium::Connector::TechnicalProduct.new(
+          "http://example.net/product_group"
+        )
+      SemanticLink.create!(
+        subject: spree_product,
+        semantic_id: "http://example.net/product_group",
+      )
+      expect(result).to eq spree_product
+    end
+
     it "returns a product referenced by URI" do
       variant.save!
       supplied_product.spree_product_uri =