Webpack has trouble dealing with some ES Modules dependencies

[minenwerfer]

Goals

1. Patch built-in Webpack config to address ESM-related bundling issues
2. Increase the portability of certain dependencies to NextJS

Non-Goals

None that I know of.

Background

When using the bson package inside a Server Action, Webpack complains of a top-level await being used. This can be patched using the following in next.config.js:

config.resolve.alias.bson = fileURLToPath(import.meta.resolve('bson').replace(/.mjs$/, '.cjs'))

I am a library developer and my library depends on the bson package, so every NextJS user that wished to integrate with my library would have to patch their configs manually, make adoption harder.

Proposal

My idea is, NextJS should provide a webpack (or nextjs) conditional export name that will be preferred over import so library developers could use this strategy to force problematic dependencies to be handled as CommonJS. Something like the following:

config.resolve.conditionNames = [
  'webpack',
  'import',
  'require',
]

So I would be able to open a PR in bson setting this conditional export to a CommonJS file and changes in next.config.js wouldn't be needed anymore. This is also great because it is very unlikely to break anything.