404 if the applicable version no longer matches (#33086)

Peter Bengtsson · web-flow · commit e541364c9acf · 2022-11-30T16:27:29.000Z
diff --git a/middleware/find-page.js b/middleware/find-page.js
@@ -24,6 +24,18 @@ export default async function findPage(
   let page = req.context.pages[req.pagePath]
   if (page && isDev && englishPrefixRegex.test(req.pagePath)) {
     page = await rereadByPath(req.pagePath, contentRoot, req.context.currentVersion)
+
+    // This can happen if the page we just re-read has changed which
+    // versions it's available in (the `versions` frontmatter) meaning
+    // it might no longer be available on the current URL.
+    if (!page.applicableVersions.includes(req.context.currentVersion)) {
+      return res
+        .status(404)
+        .send(
+          `After re-reading the page, '${req.context.currentVersion}' is no longer an applicable version. ` +
+            'A restart is required.'
+        )
+    }
   }
 
   if (page) {
diff --git a/tests/fixtures/page-with-redirects.md b/tests/fixtures/page-with-redirects.md
@@ -4,5 +4,5 @@ redirect_from:
   - /some-old-path
 versions:
   free-pro-team: '*'
+  ghec: '*'
 ---
-
diff --git a/tests/unit/find-page-middleware.js b/tests/unit/find-page-middleware.js
@@ -23,7 +23,17 @@ function makeRequestResponse(url, currentVersion = 'free-pro-team@latest') {
   req.context.currentVersion = currentVersion
   req.context.pages = {}
 
-  return [req, new http.ServerResponse(req)]
+  const res = new http.ServerResponse(req)
+  res.status = function (code) {
+    this._status = code
+    return {
+      send: function (message) {
+        this._message = message
+      }.bind(this),
+    }
+  }
+
+  return [req, res]
 }
 
 describe('find page middleware', () => {
@@ -73,7 +83,6 @@ describe('find page middleware', () => {
     })
     expect(req.context.page).toBeInstanceOf(Page)
   })
-
   test('finds it for non-fpt version URLS', async () => {
     const [req, res] = makeRequestResponse('/en/page-with-redirects', 'enterprise-cloud@latest')
     req.context.pages = {
@@ -91,6 +100,27 @@ describe('find page middleware', () => {
     expect(req.context.page).toBeInstanceOf(Page)
   })
 
+  test("will 404 if the request version doesn't match the page", async () => {
+    // The 'versions:' frontmatter on 'page-with-redirects.md' does
+    // not include ghes. So this'll eventually 404.
+    const [req, res] = makeRequestResponse('/en/page-with-redirects', 'enterprise-server@latest')
+    req.context.pages = {
+      '/en/page-with-redirects': await Page.init({
+        relativePath: 'page-with-redirects.md',
+        basePath: path.join(__dirname, '../fixtures'),
+        languageCode: 'en',
+      }),
+    }
+
+    await findPage(req, res, () => {}, {
+      isDev: true,
+      contentRoot: path.join(__dirname, '../fixtures'),
+    })
+    expect(res._status).toBe(404)
+    expect(res._message).toMatch('')
+    expect(req.context.page).toBeUndefined()
+  })
+
   test('re-reads from disk if in development mode and finds nothing', async () => {
     const [req, res] = makeRequestResponse('/en/never/heard/of')
 
