process.env.NODE_ENV suddenly UNDEFINED in current SvelteKit project

Question

Inside svelte.config.js I was using this

const dev = process.env.NODE_ENV === 'development';

to conditionally set a base path which was working fine in projects with @sveltejs/[email protected] and *.357

After installing now the most recent SvelteKit version @sveltejs/[email protected] it only results to undefined

Differences I notice is that the new project lists "vite": "^3.0.0" as devDependency and the script changed from "dev": "svelte-kit dev", to "dev": "vite dev"

Update: It's also the case for a project with @sveltejs/[email protected], [email protected], "dev": "vite dev" - so the switch was before vite 3.0

Going through the vite docs I find import.meta.env, but that's also undefined inside svelte.config.js

Switching from Node v16 to 17 didn't make a difference as well

What changed and how can I now distinguish between dev and build mode?

Hint: backticks do not work in question string.

Marcin Orlowski
– Marcin Orlowski

2022-07-21 17:27:21 +00:00
Commented Jul 21, 2022 at 17:27 — Marcin Orlowski
– Marcin Orlowski, Commented Jul 21, 2022 at 17:27

Paolo · Accepted Answer · 2022-07-21 17:21:35Z

5

The behavior you describe was introduced in 100-next384

[breaking] remove mode, prod and server from $app/env (#5602)

and here is the relevant discussion

respect --mode, and remove server, prod and mode from $app/env

I think you should use Vite capabilities to configure dev VS production/build modes.

Update

Considering better your case, a way to solve the issue is to set a value for the NODE_DEV environment variable, like (Linux/Mac):

export NODE_ENV=development && npm run dev

There are other ways to do this but at least for development it should do the trick.

edited Jul 21, 2022 at 17:21

answered Jul 21, 2022 at 15:04

Paolo

21.4k21 gold badges78 silver badges124 bronze badges

Sign up to request clarification or add additional context in comments.

5 Comments

Corrl Over a year ago

I'm not sure - is this really related to $app/env? I'm not in a src/ project file but in the svelte.config.js. I first thought it was only with the current version and somehow related to vite 3, but it's the same in a project with next.366 and [email protected]. The vite docs page you linked is where I got import.meta.env from which as stated unforunately doesn't work in the config file.

Paolo Over a year ago

I see what you say. Then, shouldn't be enough to export NODE_ENV environment variable?

Corrl Over a year ago

export how/where?

Paolo Over a year ago

it depends on your environment/os. for linux development I run export NODE_ENV='dev' npm run dev. ymmv

Corrl Over a year ago

I'm on Mac and export NODE_ENV=development && ... seems to be doing the trick, great! Thanks!!

Luck1609 · Accepted Answer · 2023-01-09 15:50:42Z

0

This might help someone in the future. I encountered this error when I created an express server in a react application. I created the server directory in the root folder of the react application and I was running both react app and express server at the same time.

answered Jan 9, 2023 at 15:50

Luck1609

3542 silver badges7 bronze badges

Collectives™ on Stack Overflow

process.env.NODE_ENV suddenly UNDEFINED in current SvelteKit project

2 Answers 2

Update

5 Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Update

5 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related