fs in _document.js

[x] I have searched the issues of this repository and believe that this is not a duplicate.

I try to use fs in _document.js, developement & build process is success, but when I tried to run in production mode. I got the message.

Error: EBADF: bad file descriptor, fstat

My understand. _document.js can use on _document.js because it only runs on server-side only right?

What else, I need to config

My Environment

Tech	Version
next	5.1
node	8.9.3
OS	OSX
browser	Chrome

[timneutkens]

@comus in development we do bundle it for the client side, the reason for this is hot reloading on _document.js

[comus]

oh, sorry, seems like next.config.js must add fs: empty for import fs, not sure how it works

module.exports = {
  webpack: function (config, { isServer }) {
    config.node = {
      fs: 'empty'
    }
    return config
  }
}