fix: fixes cookie override during redirection from server action

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

@@ -220,22 +220,38 @@ async function createRedirectRenderResult(
       if (
         headResponse.headers.get('content-type') === RSC_CONTENT_TYPE_HEADER
       ) {
-        const response = await fetch(fetchUrl, {
+        const redirectResponse = await fetch(fetchUrl, {
           method: 'GET',
           headers: forwardedHeaders,
           next: {
             // @ts-ignore
             internal: 1,
           },
         })
+        //copy cookies from the redirect response to respose we're sending before copying other headers
+        //this is needed only in case of custom server created by developer
+        //cause nextjs app dir does not allow to set cookies from components
+        const redirectResponseCookies = new ResponseCookies(
+          redirectResponse.headers
+        )
+        const responseCookies = new ResponseCookies(
+          fromNodeOutgoingHttpHeaders(res.getHeaders())
+        )
+        redirectResponseCookies.getAll().forEach((cookie) => {
+          if (typeof cookie.value === 'undefined') {
+            responseCookies.delete(cookie.name)
+          } else {
+            responseCookies.set(cookie)
+          }
+        })
         // copy the headers from the redirect response to the response we're sending
-        for (const [key, value] of response.headers) {
+        for (const [key, value] of redirectResponse.headers) {
           if (!actionsForbiddenHeaders.includes(key)) {
             res.setHeader(key, value)
           }
         }
 
-        return new FlightRenderResult(response.body!)
+        return new FlightRenderResult(redirectResponse.body!)
       }
     } catch (err) {
       // we couldn't stream the redirect response, so we'll just do a normal redirect

packages/next/src/server/lib/server-ipc/utils.ts

@@ -13,6 +13,7 @@ export const ipcForbiddenHeaders = [
 export const actionsForbiddenHeaders = [
   ...ipcForbiddenHeaders,
   'content-length',
+  'set-cookie',
 ]
 
 export const filterReqHeaders = (

test/e2e/app-dir/app-basepath-custom-server/custom-server/app/page.js

@@ -1,8 +1,12 @@
 import { redirect } from 'next/navigation'
+import { cookies } from 'next/headers'
 
 async function action() {
   'use server'
-
+  cookies().set(
+    'custom-server-action-test-cookie',
+    'custom-server-action-test-cookie-val'
+  )
   redirect('/another')
 }
 

test/e2e/app-dir/app-basepath-custom-server/custom-server/server.js

@@ -18,7 +18,10 @@ async function main() {
     try {
       const parsedUrl = parse(req.url, true)
       const { pathname } = parsedUrl
-
+      res.setHeader(
+        'set-cookie',
+        'custom-server-test-cookie=custom-server-test-cookie-val'
+      )
       if (pathname.startsWith('/base')) {
         await handle(req, res, parsedUrl)
       } else {

test/e2e/app-dir/app-basepath-custom-server/index.test.ts

@@ -1,6 +1,6 @@
-import { join } from 'path'
 import { createNextDescribe } from 'e2e-utils'
-import { retry } from 'next-test-utils'
+import { check, retry } from 'next-test-utils'
+import { join } from 'path'
 
 createNextDescribe(
   'custom-app-server-action-redirect',
@@ -35,5 +35,26 @@ createNextDescribe(
       // Count should still be 2 as the browser should not have reloaded the page.
       expect(await getCount()).toBe('Count: 2')
     })
+
+    it('redirects with proper cookies set from both redirect response and post respose', async () => {
+      const browser = await next.browser('/base')
+
+      await browser.elementById('submit-server-action-redirect').click()
+
+      expect(await browser.waitForElementByCss('#another').text()).toBe(
+        'Another Page'
+      )
+      expect(await browser.url()).toBe(
+        `http://localhost:${next.appPort}/base/another`
+      )
+      await check(
+        () => browser.eval('document.cookie'),
+        /custom-server-test-cookie/
+      )
+      await check(
+        () => browser.eval('document.cookie'),
+        /custom-server-action-test-cookie/
+      )
+    })
   }
 )