Rsc header and query params always null on middleware

[zecka]

Link to the code that reproduces this issue

https://codesandbox.io/p/devbox/nextjs-middleware-get-rsc-query-params-and-header-vfy9hk?file=%2Fmiddleware.ts%3A23%2C15

To Reproduce

1. Go to https://codesandbox.io/p/devbox/nextjs-middleware-get-rsc-query-params-and-header-vfy9hk?file=%2Fmiddleware.ts%3A23%2C15
2. Open network tab on your browser
3. Clique on link "Page2?test=1"
4. You will a request to "https://vfy9hk-3000.csb.app/page2?test=1&_rsc=1dou9"

Current vs. Expected behavior

Check console query params test is successfully log but _rsc params is null. rsc header is also null

Provide environment information

Operating System:
  Platform: linux
  Arch: x64
  Version: #1 SMP PREEMPT_DYNAMIC Sun Aug  6 20:05:33 UTC 2023
  Available memory (MB): 4102
  Available CPU cores: 2
Binaries:
  Node: 20.9.0
  npm: 9.8.1
  Yarn: 1.22.19
  pnpm: 8.10.2
Relevant Packages:
  next: 14.3.0-canary.63 // Latest available version is detected (14.3.0-canary.63).
  eslint-config-next: N/A
  react: 19.0.0-beta-4508873393-20240430
  react-dom: 19.0.0-beta-4508873393-20240430
  typescript: 5.1.3
Next.js Config:
  output: N/A

Which area(s) are affected? (Select all that apply)

Middleware

Which stage(s) are affected? (Select all that apply)

next dev (local), next build (local), next start (local), Other (Deployed)

Additional context

No response

[tigerabrodi]

@zecka good catch!

Is this the most recent version, Next.js 14.2?

[zecka]

@tigerabrodi Yes I tested it on 14.2 and 14.3 and Both have the issue

[PSoltes]

is there an ETA on this being fixed?

Edit by maintainer bot: Comment was automatically minimized because it was considered unhelpful. (If you think this was by mistake, let us know). Please only comment if it adds context to the issue. If you want to express that you have the same problem, use the upvote 👍 on the issue description or subscribe to the issue for updates. Thanks!

[lubieowoce]

This is currently intended behavior. See e.g. test here

next.js/test/e2e/app-dir/navigation/middleware.js

Lines 14 to 19 in a5f30e6

	const rscQuery = request.nextUrl.searchParams.get(NEXT_RSC_UNION_QUERY)
	// Test that the RSC query is not present in the middleware
	if (rscQuery) {
	throw new Error('RSC query should not be present in the middleware')
	}

[PSoltes]

If it is intended behaviour, why is this issue open as a bug? Maybe change it to feature request? But also my personal opinion kinda weird to hide it.

[marco910]

It would be pretty nice to have access to the rsc param in the middleware. There is a use case in our app where we need this

[saikatmitra91]

One use case:
If you have a middleware where authentication is being done, too many prefetch RSC calls lead to rate limit on our auth service.

Is there any alternate approach to detect RSC calls ?