With next.js, why did I suddenly start seeing Module not found: Error: Can't resolve 'fs'?

Question

I changed nothing, but am using "next": "9.4.4", and I see:

Module not found: Can't resolve 'fs' in 'web/node_modules/graceful-fs'
Could not find files for /app/d/[id] in .next/build-manifest.json
ModuleNotFoundError: Module not found: Error: Can't resolve 'fs' in 'web/node_modules/graceful-fs'

What could I be doing wrong?

Answer 1

Looks like you're not in an /api directory. The client side code won't be able to import fs, only the API files will

Answer 2

Your component might be rendering on the client-side. Check that places you assume are rendered on the server (getStaticProps/getServerSideProps) might be hydrating your component and trying to run code you think should run on the server actually on the client.