fix: add unmapped surrogate key for 404.html (#633)

fixes #632

Author: tripodsan

src/steps/fetch-404.js

@@ -40,5 +40,19 @@ export default async function fetch404(state, req, res) {
 
   // set 404 keys in any case
   const pathKey = await getPathKey(state);
-  res.headers.set('x-surrogate-key', `${pathKey} ${contentBusId} ${ref}--${repo}--${owner}_404 ${ref}--${repo}--${owner}_code`);
+  const keys = [
+    pathKey,
+    contentBusId,
+    `${ref}--${repo}--${owner}_404`,
+    `${ref}--${repo}--${owner}_code`,
+  ];
+
+  if (state.info.unmappedPath) {
+    keys.push(await getPathKey({
+      contentBusId,
+      info: { path: state.info.unmappedPath },
+    }));
+  }
+
+  res.headers.set('x-surrogate-key', keys.join(' '));
 }

test/rendering.test.js

@@ -120,6 +120,7 @@ const DEFAULT_CONFIG = {
     '/products': '/generic-product',
     '/articles/': '/special/default-article',
     '/app': '/spa/index.html',
+    '/broken': '/not-a-page',
   },
   headers: HEADERS,
   metadata: {
@@ -527,6 +528,18 @@ describe('Rendering', () => {
       assert.strictEqual(body.trim(), '');
     });
 
+    it('renders 404 for folder mapped not found', async () => {
+      const { headers, body } = await testRender(new URL('https://helix-pipeline.com/broken/folder'), 'html', 404);
+      assert.deepStrictEqual(Object.fromEntries(headers.entries()), {
+        'access-control-allow-origin': '*',
+        'content-type': 'text/html; charset=utf-8',
+        link: '</scripts/scripts.js>; rel=modulepreload; as=script; crossorigin=use-credentials',
+        'x-error': 'failed to load /not-a-page.md from content-bus: 404',
+        'x-surrogate-key': 'gPHXKWdMY_R8KV2Z foo-id super-test--helix-pages--adobe_404 super-test--helix-pages--adobe_code QJqsV4atnOA47sHc',
+      });
+      assert.strictEqual(body.trim(), '');
+    });
+
     it('renders 301 for redirect file', async () => {
       loader.headers('one-section.md', 'x-amz-meta-redirect-location', 'https://www.adobe.com');
       const ret = await render(new URL('https://localhost/one-section'), '', 301);