Create canonical product layer scaffold

tests/test_canonical_layer.py

@@ -0,0 +1,42 @@
+import unittest
+
+import build_canonical_layer
+
+
+class CanonicalLayerTests(unittest.TestCase):
+    def test_build_canonical_layer_seeds_one_canonical_per_observed_product(self):
+        observed_rows = [
+            {
+                "observed_product_id": "gobs_1",
+                "representative_name_norm": "GALA APPLE",
+                "representative_brand": "SB",
+                "representative_variant": "",
+                "representative_size_value": "5",
+                "representative_size_unit": "lb",
+                "representative_pack_qty": "",
+                "representative_measure_type": "weight",
+            },
+            {
+                "observed_product_id": "gobs_2",
+                "representative_name_norm": "ROTINI",
+                "representative_brand": "",
+                "representative_variant": "",
+                "representative_size_value": "16",
+                "representative_size_unit": "oz",
+                "representative_pack_qty": "",
+                "representative_measure_type": "weight",
+            },
+        ]
+
+        canonicals, links = build_canonical_layer.build_canonical_layer(observed_rows)
+
+        self.assertEqual(2, len(canonicals))
+        self.assertEqual(2, len(links))
+        self.assertEqual("GALA APPLE", canonicals[0]["canonical_name"])
+        self.assertEqual("5", canonicals[0]["normalized_quantity"])
+        self.assertEqual("lb", canonicals[0]["normalized_quantity_unit"])
+        self.assertEqual("seed_observed_product", links[0]["link_method"])
+
+
+if __name__ == "__main__":
+    unittest.main()