fix(SPD): Correct and ingest invalid SPD postcodes

Reintroduces fix from #578

Some postcodes on SPD have an extra character appended. Since these are
picked up as invalid postcodes, they can no longer be queried

This change will ingest the first instance of these invalid postcodes
(i.e. those ending with A) and drop all others

src/app/models/scottish_postcode.ts

@@ -73,6 +73,24 @@ const findQuery = `
   WHERE pc_compact=$1 
 `;
 
+const EXCEPTION_REGEX = /A$/;
+
+/**
+ * Validates and potentially mutates a CSV row for ingest
+ *
+ * Unfortunately SPD appends extra characters to some postcodes. This method returns null when these cases are met, unless the postcode ends in `A`.
+ *
+ * Postcodes suffixed with `A` are made valid and returned to the stream for ingest
+ */
+const clean = (row: string[]) => {
+  const postcode = row[0];
+  if (isValid(postcode)) return row;
+  // Reject if invalid postcide has a non-A suffix
+  if (postcode.match(EXCEPTION_REGEX) === null) return null;
+  row[0] = postcode.replace(EXCEPTION_REGEX, "");
+  return row;
+};
+
 const SPD_COL_MAPPINGS = Object.freeze([
   { column: "postcode", method: (row: RowExtract) => row.extract("Postcode") },
   {
@@ -137,6 +155,7 @@ const seedPostcodes = ({ extractor, filepath }: SeedPostcodesOptions) => {
   return methods.csvSeed({
     filepath: [filepath],
     transform: (row: RowExtract) => {
+      clean(row);
       row.extract = (code: string) => extractor(row, code);
       if (row.extract("Postcode") === "Postcode") return null; // Skip if header
       if (row.extract("DateOfDeletion").length !== 0) return null; // Skip row if terminated

test/scottish_postcode.unit.ts

@@ -57,6 +57,11 @@ describe("Scottish Postcode Model", () => {
         const result = await query(q);
         assert.isTrue(result.rows[0].count > 0);
       });
+
+      it("loads postcodes suffixed with additional character", async () => {
+        const result = await ScottishPostcode.find("PA31 8UA");
+        assert.isNotNull(result);
+      });
     });
   });