ModuleError: Cannot Resolve 'fs' used in markdown blog-starter example

[dillionmegida]

What version of Next.js are you using?

9.5.1

What version of Node.js are you using?

12.18.4

What browser are you using?

Chrome

What operating system are you using?

macOS

How are you deploying your application?

Vercel

Describe the Bug

Following the markdown blog starter, the fs module was used in the lib/api.js file to do some reading from a directory.

On running npm run dev, and accessing the blog page, I get:

event - build page: /blog/[slug]
event - build page: /blog/[slug]
event - compiled successfully
error - ./utils/posts/index.ts
Module not found: Can't resolve 'fs' in ...

Expected Behavior

I followed everything in the blog-starter, so I expected the page to load without errors.

To Reproduce

The markdown blog starter template was what I used before getting the error.

Actually, I discovered a solution that worked for me, but I'm just surprised that the blog-starter did not use the solution.

In this discussion, the solution was to have a next.config.js configured like so:

module.exports = {
  webpack: (config, { isServer }) => {
    // Fixes npm packages that depend on `fs` module
    if (!isServer) {
      config.node = {
        fs: 'empty'
      }
    }

    return config
  }
}

But the blog starter did not have any next.config.js file so I'm wondering how it deployed successfully.

I've got the solution already but I think the starter working without the next config file should be addressed documentation-wise or any ways at all.

Awesome job, team. Thank you!

[Timer]

This was likely caused by an edit you made to the example. Could you please share your project?

[dillionmegida]

Hi @Timer, the project is currently private in development. I'm sorry I can't share.
But I followed the blog-starter template and expected it to work without further configurations.

[Timer]

It does work fine! The two files you referenced in your logs above do not belong to that example:

event - build page: /blog/[slug]
error - ./utils/posts/index.ts

This would indicate you have pages/blog/[slug].ts and utils/posts/index.ts, neither of which exist in the example you linked.

I'll close this issue since it's not actionable without you sharing a reproduction.

[dillionmegida]

I'm sorry about that.

The main issue was the fs module throwing errors until I added next.config.js. I didn't expect to have any more configurations since the template didn't have them too.

Thank you, once again.

[Timer]

This is caused to an error in your user code. No next.config.js is necessary if you fix the issue in your application. Happy to help you find it if you can share some code!

[balazsorban44]

This issue has been automatically locked due to no recent activity. If you are running into a similar issue, please create a new issue with the steps to reproduce. Thank you.