[🐛 Bug]: Failed to read header in page / layout after setting it in the middleware

[clmnin]

next-on-pages environment related information

System:
Platform: darwin
Arch: arm64
Version: Darwin Kernel Version 23.5.0: Wed May 1 20:14:38 PDT 2024; root:xnu-10063.121.3~5/RELEASE_ARM64_T6020
CPU: (10) arm64 Apple M2 Pro
Memory: 16 GB
Shell: /bin/zsh
Package Manager Used: npm (10.5.0)

Relevant Packages:
@cloudflare/next-on-pages: 1.11.3
vercel: 34.2.4
next: 14.1.0

Description

Cloudflare next-on-pages fails to read header in next js pages/layout after setting it in the middleware.

Reproduction

I have created a minimal reproducible example in this repo - clmnin/cf-middleware-set-header

How to set it up

git clone https://github.com/clmnin/cf-middleware-set-header.git
cd cf-middleware-set-header
npm i

Run NextJS Dev to see what are the expected outputs

npm run dev
# console log "token-value" for the middleware, page and layout
# ▲ Next.js 14.1.0
# - Local:        http://localhost:3000
# 1. middleware: token-value
# 2. page: token-value
# 3. layout: token-value

This is the expected output for a next js app. The page and layout routes get the response passed by the middleware.

Run Cloudflare pages preview using wrangler

npm run preview
# fails to console log "token-value" for the middleware, page and layout
# [wrangler:inf] Ready on http://localhost:8788
# 1. middleware: token-value
# 2. page: null
# 3. layout: null

Pages Deployment Method

None

Pages Deployment ID

No response

Additional Information

No response

Would you like to help?

• Would you like to help fixing this bug?

[dario-piotrowicz]

Hi @clmnin thanks a bunch for the issue 🙂
(and thanks so very much for the minimal reproduction! that's been extremely helpful!!! ❤️)

Sorry it took me a while to get to it 🙇

#811 that should fix it, if you want please feel free to try the PR's prerelease and let me know if that works for you 🙏