Auth0 Provider ignores NEXTAUTH_URL (with basePath) in prod

[ss-ravi]

Provider type

Auth0

Environment

  System:
    OS: macOS 14.5
    CPU: (10) arm64 Apple M2 Pro
    Memory: 548.75 MB / 32.00 GB
    Shell: 5.9 - /bin/zsh
  Binaries:
    Node: 18.18.2 - ~/.nvm/versions/node/v18.18.2/bin/node
    Yarn: 1.22.22 - ~/.nvm/versions/node/v18.18.2/bin/yarn
    npm: 9.8.1 - ~/.nvm/versions/node/v18.18.2/bin/npm
    pnpm: 8.15.3 - ~/.nvm/versions/node/v18.18.2/bin/pnpm
  Browsers:
    Chrome: 129.0.6668.60
    Safari: 17.5
  npmPackages:
    next: 14.2.13 => 14.2.13 
    next-auth: ^4.24.8 => 4.24.8 
    react: ^18 => 18.3.1 

Reproduction URL

https://github.com/ss-ravi/auth0-provider-test

Describe the issue

after the auth0 sign in, the browser is being redirected to https://my-app.vercel.app/api/auth/callback/auth0 even though my NEXTAUTH_URL is set to https://my-app.vercel.app/app/api/auth.
In localhost it works as expected and the app redirects to http://localhost:3000/app/api/auth/callback/auth0.

How to reproduce

• Clone the repo
• Set it up to deploy on Vercel
• set the environment variables:
  • NEXT_PUBLIC_BASE_PATH=/app
  • AUTH0_CLIENT_ID=xxx
  • AUTH0_CLIENT_SECRET=xxx
  • AUTH0_ENDPOINT=https://xxx.com
  • NEXTAUTH_URL=https://my-app.vercel.app/app/api/auth (switch to your app's Vercel domain)
  • NEXTAUTH_SECRET=xxx
• deploy the app
• the callbackUrl will not include the basePath and it will show 404

Expected behavior

The callbackUrl should include the basePath (as it is set in the NEXTAUTH_URL)

Additional info

I also tried to set the redirectUri manually, but without success: commit

Relevant code

• nextjs config
• _app
• nextauth config
• test page