gatsby-config/node.js doesn't support ESM import/export

Summary

Node v14 is out and with it the removal of the Experimental Modules warning! 🎉

I installed it, added "type": "module" to package.json, used export default in gatsby-config.js and took the default starter for a spin. This is what I got:

Error: [ERR_REQUIRE_ESM]: Must use import to load ES Module: gatsby-config.js require() of ES modules is not supported. require() of gatsby-config.js from node_modules/gatsby/dist/bootstrap/get-config-file.js is an ES module file as it is a .js file whose nearest parent package.json contains “type”: “module” which defines all .js files in that package scope as ES modules. Instead rename gatsby-config.js to end in .cjs, change the requiring code to use import(), or remove “type”: “module” from package.json.

Sounds like Gatsby, specifically gatsby/dist/bootstrap/get-config-file.js, stands in the way of using ESM import/export syntax. I think it’s time to make gatsby’s config and node APIs ESM-ready. 🚀

Basic example

export default {
  siteMetadata: {
    title: `Gatsby Default Starter`,
    author: `@gatsbyjs`,
  },
  plugins: [
    `gatsby-plugin-react-helmet`,
    // ...
  ],
}

Motivation

Would be really cool if we could finally use a single import/export system all throughout our Gatsby projects! As the release announcement states:

It is our belief that the current implementation offers a future proof model to authoring ESM modules that paves the path to Universal JavaScript.

If that doesn’t get you excited, you must be in the wrong line of work. 😄

[ghost]

@LekoArts @KyleAMathews Node 16 is out, this is no longer experimental and should be reopened.

[karlhorky]

Yeah, Gatsby not supporting ESM will become a big problem in the next weeks as people upgrade to the latest remark packages, which are full ESM.

@LekoArts would recommend the team reopening this one - it should be an issue, not a feature request.

cc @wooorm