How do I use native fetch when running n8n with node.js 18?

Questions
1

Describe the issue/error/question

I’d like to use the native version of fetch as one would with node.js version 18. Is this supported?
I’m running n8n with node.js 18 set via NODE_VERSION.
Also tried setting NODE_FUNCTION_ALLOW_BUILTIN=https,fetch

What is the error message (if any)?

“ReferenceError: fetch is not defined” when using the Code node.

Information on your n8n setup

  • n8n version: latest as of 3/13/23
  • Database you’re using (default: SQLite): sqlite
  • Running n8n with the execution process [own(default), main]: own
  • Running n8n via [Docker, npm, n8n.cloud, desktop app]: docker
2

Welcome to the community @eddywashere!

Sorry, not totally up-to-date on that topic. Is it only part of Node.js v18? Because the default n8n Docker image currently uses Node.js v16.

3

as Jan pointed out, our docker image ships with node 16 right now, so there is no built in native fetch api available.

However we do ship with node-fetch. So you can set NODE_FUNCTION_ALLOW_EXTERNAL=node-fetch and then try using fetch by importing the shim via const fetch = require('node-fetch');

4

It was behind a feature flag in v17. Might be worth tracking someone in case node-fetch causes a conflict when y’all do upgrade. But maybe it already handles when fetch is available globally.

Anyway, this is helpful. I miss understood where NODE_VERSION gets applied and can’t simply be overridden without rebuilding the image

Thanks for the quick responses!