Error because `import.meta.url` is undefined

[nichoth]

Describe the bug

In order to require older modules, I've been writing this:

import { createRequire } from 'module';
const require = createRequire(import.meta.url)

This works if I run the file with node my-file.js. However, I’ve been using the package netlify-cli to run things locally, and when I do that, it logs an error saying that import.meta.url is undefined:

The argument ‘filename’ must be a file URL object, file URL string, or absolute path string. Received undefined

If you want to see in more detail, this is all open source:

https://github.com/nichoth/ssc-server/blob/1965d193da893bb98e98bd9962717d65c32a4f83/netlify/functions/profile/profile.js#L14

---

This is relevant to this post

Steps to reproduce

Either

Use a lambda function that includes import.meta.url, and run it with netlify-cli

or

clone my example at this commit within git :

https://github.com/nichoth/ssc-server/blob/1965d193da893bb98e98bd9962717d65c32a4f83/netlify/functions/profile/profile.js#L14

Then run npm start, which will run netlify dev

Configuration

[build]
  command = "npm run build"
  functions = "netlify/functions"
  publish = "public"

  ## more info on configuring this file: https://www.netlify.com/docs/netlify-toml-reference/

[dev]
  autoLaunch = false
  publish = "public" # Folder with the static content for _redirect file

[template.environment]
  FAUNADB_SERVER_SECRET = "faunaDB secret"
  CLOUDINARY_API_SECRET = "cloudinary secret"
  CLOUDINARY_CLOUD_NAME="cloudinary cloud name"
  CLOUDINARY_API_KEY="cloudinary API key"
  PUBLIC_KEY = "public key"
  SECRET_KEY = "secret key"

[functions]
  node_bundler = "esbuild"

[functions.profile]
  external_node_modules = ["@nichoth/ssc"]

Environment

  System:
    OS: macOS 12.3.1
    CPU: (8) arm64 Apple M1
    Memory: 70.31 MB / 16.00 GB
    Shell: 5.8 - /bin/zsh
  Binaries:
    Node: 16.13.1 - ~/.nvm/versions/node/v16.13.1/bin/node
    Yarn: 1.22.18 - ~/.nvm/versions/node/v16.13.1/bin/yarn
    npm: 8.3.0 - ~/.nvm/versions/node/v16.13.1/bin/npm
  npmPackages:
    netlify-cli: ^10.3.0 => 10.3.0 
  npmGlobalPackages:
    netlify-cli: 9.16.6

[alexcroox]

@nichoth did you ever resolve this? Running ESM with import.meta.url is giving me the same error on AWS Lambda 16x

[nichoth]

@alexcroox No actually, I think I refactored so that everything is using require on the server.

[alexcroox]

I don't blame you. The node ecosystem still isn't ready for ESM without a lot of pain during the intial stages of setting up a new project...

For any other weary travellers I solved this on AWS by using import dirname from 'es-dirname'.

dirname() is a hack that throws an error and reads the file path from the error stack!

[danez]

We do not yet support pure ESM modules in netlify functions. Currently, it will all be compiled to commonjs.

Supporting this is on our roadmap though. Ref: https://github.com/netlify/zip-it-and-ship-it/issues/750

[thescientist13]

Would love to see support for this, especially with Node 18 and Web API adoption on the backend picking up steam, using import.meta.url + URL would be great to have.