Read page name from work store in server module map proxy

packages/next/src/build/templates/edge-app-route.ts

@@ -21,7 +21,6 @@ if (rscManifest && rscServerManifest) {
     serverActionsManifest: rscServerManifest,
     serverModuleMap: createServerModuleMap({
       serverActionsManifest: rscServerManifest,
-      pageName: 'VAR_PAGE',
     }),
   })
 }

packages/next/src/build/templates/edge-ssr-app.ts

@@ -60,7 +60,6 @@ if (rscManifest && rscServerManifest) {
     serverActionsManifest: rscServerManifest,
     serverModuleMap: createServerModuleMap({
       serverActionsManifest: rscServerManifest,
-      pageName: 'VAR_PAGE',
     }),
   })
 }

packages/next/src/server/app-render/action-utils.ts

@@ -2,26 +2,44 @@ import type { ActionManifest } from '../../build/webpack/plugins/flight-client-e
 import { normalizeAppPath } from '../../shared/lib/router/utils/app-paths'
 import { pathHasPrefix } from '../../shared/lib/router/utils/path-has-prefix'
 import { removePathPrefix } from '../../shared/lib/router/utils/remove-path-prefix'
+import { workAsyncStorage } from './work-async-storage.external'
 
 // This function creates a Flight-acceptable server module map proxy from our
 // Server Reference Manifest similar to our client module map.
 // This is because our manifest contains a lot of internal Next.js data that
 // are relevant to the runtime, workers, etc. that React doesn't need to know.
 export function createServerModuleMap({
   serverActionsManifest,
-  pageName,
 }: {
   serverActionsManifest: ActionManifest
-  pageName: string
 }) {
   return new Proxy(
     {},
     {
       get: (_, id: string) => {
-        const workerEntry =
+        const workers =
           serverActionsManifest[
             process.env.NEXT_RUNTIME === 'edge' ? 'edge' : 'node'
-          ][id].workers[normalizeWorkerPageName(pageName)]
+          ][id].workers
+
+        const workStore = workAsyncStorage.getStore()
+
+        let workerEntry:
+          | { moduleId: string | number; async: boolean }
+          | undefined
+
+        if (workStore) {
+          workerEntry = workers[normalizeWorkerPageName(workStore.page)]
+        } else {
+          // If there's no work store defined, we can assume that a server
+          // module map is needed during module evaluation, e.g. to create a
+          // server action using a higher-order function. Therefore it should be
+          // safe to return any entry from the manifest that matches the action
+          // ID. They all refer to the same module ID, which must also exist in
+          // the current page bundle. TODO: This is currently not guaranteed in
+          // Turbopack, and needs to be fixed.
+          workerEntry = Object.values(workers).at(0)
+        }
 
         if (typeof workerEntry === 'string') {
           return { id: workerEntry, name: id, chunks: [] }

packages/next/src/server/app-render/app-render.tsx

@@ -1057,10 +1057,7 @@ async function renderToHTMLOrFlightImpl(
   // TODO: fix this typescript
   const clientReferenceManifest = renderOpts.clientReferenceManifest!
 
-  const serverModuleMap = createServerModuleMap({
-    serverActionsManifest,
-    pageName: renderOpts.page,
-  })
+  const serverModuleMap = createServerModuleMap({ serverActionsManifest })
 
   setReferenceManifestsSingleton({
     clientReferenceManifest,

packages/next/src/server/load-components.ts

@@ -172,16 +172,15 @@ async function loadComponentsImpl<N = any>({
       : null,
   ])
 
-  // Before requring the actual page module, we have to set the reference manifests
-  // to our global store so Server Action's encryption util can access to them
-  // at the top level of the page module.
+  // Before requiring the actual page module, we have to set the reference
+  // manifests to our global store so Server Action's encryption util can access
+  // to them at the top level of the page module.
   if (serverActionsManifest && clientReferenceManifest) {
     setReferenceManifestsSingleton({
       clientReferenceManifest,
       serverActionsManifest,
       serverModuleMap: createServerModuleMap({
         serverActionsManifest,
-        pageName: page,
       }),
     })
   }