Fix DFC context in spec example

engines/dfc_provider/app/services/quantitative_value_builder.rb

@@ -110,7 +110,7 @@ class QuantitativeValueBuilder < DfcBuilder
     else
       # Labels may be provided one day:
       # https://github.com/datafoodconsortium/connector-ruby/issues/18
-      label = unit.semanticId.split("#").last || "items"
+      label = unit.try(:semanticId)&.split("#")&.last || "items"
       ["items", label, 1]
     end
   end

engines/dfc_provider/spec/requests/supplied_products_spec.rb

@@ -32,6 +32,9 @@ describe "SuppliedProducts", type: :request, swagger_doc: "dfc-v1.7/swagger.yaml
             'dfc-b': "http://static.datafoodconsortium.org/ontologies/DFC_BusinessOntology.owl#",
             'dfc-m': "http://static.datafoodconsortium.org/data/measures.rdf#",
             'dfc-pt': "http://static.datafoodconsortium.org/data/productTypes.rdf#",
+            'dfc-b:hasUnit': {
+              '@type': "@id"
+            },
           },
           '@id': "http://test.host/api/dfc-v1.7/enterprises/6201/supplied_products/0",
           '@type': "dfc-b:SuppliedProduct",

swagger/dfc-v1.7/swagger.yaml

@@ -330,7 +330,7 @@ paths:
                     dfc-b:hasType: http://static.datafoodconsortium.org/data/productTypes.rdf#non-local-vegetable
                     dfc-b:hasQuantity:
                       "@type": dfc-b:QuantitativeValue
-                      dfc-b:hasUnit: dfc-m:Piece
+                      dfc-b:hasUnit: dfc-m:Gram
                       dfc-b:value: 3.0
                     dfc-b:alcoholPercentage: 0.0
                     dfc-b:lifetime: ''
@@ -345,6 +345,8 @@ paths:
                   dfc-b: http://static.datafoodconsortium.org/ontologies/DFC_BusinessOntology.owl#
                   dfc-m: http://static.datafoodconsortium.org/data/measures.rdf#
                   dfc-pt: http://static.datafoodconsortium.org/data/productTypes.rdf#
+                  dfc-b:hasUnit:
+                    "@type": "@id"
                 "@id": http://test.host/api/dfc-v1.7/enterprises/6201/supplied_products/0
                 "@type": dfc-b:SuppliedProduct
                 dfc-b:name: Apple