feat: support upserting tables with only unique constraint(s) (#680)

* feat: support upserting tables with only unique constraint(s)

* test: update tests

* test: fix syntax

* test: fix expected set size

Author: bchrobot

src/__tests__/main.test.ts

@@ -81,6 +81,12 @@ test.beforeEach(async (t) => {
         name text
       )
   `);
+  await t.context.client.query(`
+    create table just_unique_constraints (
+      name text,
+      unique (name)
+    )
+  `);
   await initializePostgraphile(t);
 });
 
@@ -221,17 +227,18 @@ const create = async (
   return execGqlOp(t, nanographql(mutation));
 };
 
-test("ignores tables without primary keys", async (t) => {
+test("ignores tables without primary keys or unique constraints", async (t) => {
   await create(t);
   const res = await fetchMutationTypes(t);
   const upsertMutations = new Set(
     res.data.__type.fields
       .map(({ name }) => name)
       .filter((name) => name.startsWith("upsert"))
   );
-  t.assert(upsertMutations.size === 2);
+  t.assert(upsertMutations.size === 3);
   t.assert(upsertMutations.has("upsertBike"));
   t.assert(upsertMutations.has("upsertRole"));
+  t.assert(upsertMutations.has("upsertJustUniqueConstraint"));
 });
 
 test("upsert crud - match primary key constraint", async (t) => {

src/postgraphile-upsert.ts

@@ -27,14 +27,15 @@ export const PgMutationUpsertPlugin: Plugin = (builder) => {
     ).filter((con) => con.type === "u" || con.type === "p");
     const upsertFieldsByName = (pgIntrospectionResultsByKind.class as PgTable[])
       .filter(
-        (table) =>
-          !!table.namespace &&
-          !!table.primaryKeyConstraint &&
-          !omit(table, "upsert") &&
-          table.isSelectable &&
-          table.isInsertable &&
-          table.isUpdatable
-      )
+        (table) => {
+          const hasUniqueConstraint = allUniqueConstraints.some((c) => c.classId === table.id);
+          return !!table.namespace &&
+            (!!table.primaryKeyConstraint || hasUniqueConstraint) &&
+            !omit(table, "upsert") &&
+            table.isSelectable &&
+            table.isInsertable &&
+            table.isUpdatable
+      })
       .reduce<GraphQLFieldConfigMap<unknown, unknown>>((fnsByName, table) => {
         const gqlTable = pgGetGqlTypeByTypeIdAndModifier(table.type.id, null);
         if (!gqlTable) return fnsByName;