From e50ad14afab9efa9054f76d6ce64cfcb504b01c4 Mon Sep 17 00:00:00 2001
From: JJ Kasper <jj@jjsweb.site>
Date: Fri, 6 Sep 2024 14:56:37 -0700
Subject: [PATCH] Fix middleware fallback: false case (#69799)

This ensures we properly set the request meta during our middleware
invoke so that the `NoFallbackError` bubbling is handled properly.
Without these fields set we bubble the error unexpectedly causing an
unexpected 500 instead of a 404.

x-ref: https://github.com/vercel/next.js/pull/66987
Closes: https://github.com/vercel/next.js/issues/69428
---
 .../server/lib/router-utils/resolve-routes.ts |  3 ++
 .../app/pages/ssg-fallback-false/[slug].js    | 53 +++++++++++++++++++
 .../e2e/middleware-general/test/index.test.ts |  9 ++++
 3 files changed, 65 insertions(+)
 create mode 100644 test/e2e/middleware-general/app/pages/ssg-fallback-false/[slug].js

diff --git a/packages/next/src/server/lib/router-utils/resolve-routes.ts b/packages/next/src/server/lib/router-utils/resolve-routes.ts
index 1250838f93447..7b9d119eb2d54 100644
--- a/packages/next/src/server/lib/router-utils/resolve-routes.ts
+++ b/packages/next/src/server/lib/router-utils/resolve-routes.ts
@@ -471,6 +471,9 @@ export function getResolveRoutes(
               throw new Error(`Failed to initialize render server "middleware"`)
             }
 
+            addRequestMeta(req, 'invokePath', '')
+            addRequestMeta(req, 'invokeOutput', '')
+            addRequestMeta(req, 'invokeQuery', {})
             addRequestMeta(req, 'middlewareInvoke', true)
             debug('invoking middleware', req.url, req.headers)
 
diff --git a/test/e2e/middleware-general/app/pages/ssg-fallback-false/[slug].js b/test/e2e/middleware-general/app/pages/ssg-fallback-false/[slug].js
new file mode 100644
index 0000000000000..ac8f4401f31db
--- /dev/null
+++ b/test/e2e/middleware-general/app/pages/ssg-fallback-false/[slug].js
@@ -0,0 +1,53 @@
+import { useRouter } from 'next/router'
+import { useEffect } from 'react'
+import { useState } from 'react'
+
+export default function Page(props) {
+  const router = useRouter()
+  const [asPath, setAsPath] = useState(
+    router.isReady ? router.asPath : router.href
+  )
+
+  if (!props.params) {
+    console.error('props', props)
+    throw new Error('missing props!!!')
+  }
+
+  useEffect(() => {
+    if (router.isReady) {
+      setAsPath(router.asPath)
+    }
+  }, [router.asPath, router.isReady])
+
+  return (
+    <>
+      <p id="ssg">/blog/[slug]</p>
+      <p id="query">{JSON.stringify(router.query)}</p>
+      <p id="pathname">{router.pathname}</p>
+      <p id="as-path">{asPath}</p>
+      <p id="props">{JSON.stringify(props)}</p>
+    </>
+  )
+}
+
+export function getStaticProps({ params }) {
+  if (params.slug.includes('not-found')) {
+    return {
+      notFound: true,
+    }
+  }
+
+  return {
+    props: {
+      now: Date.now(),
+      params,
+    },
+  }
+}
+
+export function getStaticPaths() {
+  return {
+    paths: ['/ssg-fallback-false/first', '/ssg-fallback-false/hello'],
+    fallback: false,
+  }
+}
diff --git a/test/e2e/middleware-general/test/index.test.ts b/test/e2e/middleware-general/test/index.test.ts
index 8112918dcdfb9..70e5c8a2590f9 100644
--- a/test/e2e/middleware-general/test/index.test.ts
+++ b/test/e2e/middleware-general/test/index.test.ts
@@ -102,6 +102,15 @@ describe('Middleware Runtime', () => {
   }
 
   function runTests({ i18n }: { i18n?: boolean }) {
+    it('should handle 404 on fallback: false route correctly', async () => {
+      const res = await next.fetch('/ssg-fallback-false/first')
+      expect(res.status).toBe(200)
+      expect(await res.text()).toContain('blog')
+
+      const res2 = await next.fetch('/ssg-fallback-false/non-existent')
+      expect(res2.status).toBe(404)
+    })
+
     it('should work with notFound: true correctly', async () => {
       const browser = await next.browser('/ssr-page')
       await browser.eval('window.next.router.push("/ssg/not-found-1")')