Hi folks,

I'm trying out using dotenv to dynamically set different values for url in the file docusaurus.config.js

For example...

In docusaurus.config.js, I have the following relevant lines...

// load environment variables from relavent .env file
require('dotenv').config({ path: `.env.${process.env.NODE_ENV}` })
...etc
const config = {
  title: 'my title',
  tagline: 'my tagline',
  url: process.env.DOCS_URL,
etc...

Then, I have separate dotenv files as such

// .env.development
DOCS_URL=http://localhost:3000

and

// .env.production
DOCS_URL=https://my-docs.someurl

Now, with this config setup, if I run npm start, everything works fine. NODE_ENV gets set to development, the relevant dotenv file gets loaded, all is good.

However, if I run npm run build, no joy. A quick check of console.log(process.env.NODE_ENV); inside docusaurus.config.js reveals that in this context, NODE_ENV is undefined.

Would anyone be able to assist? Am I missing something here?

Further info.

I made the following second attempt to check something...

I added a fallback value for that url config setting in case the dotenv config value can't be evaluated.

// load environment variables from relavent .env file
require('dotenv').config({ path: `.env.${process.env.NODE_ENV}` })
console.log("process.env.NODE_ENV is: ", process.env.NODE_ENV);
...etc
const config = {
  title: 'my title',
  tagline: 'my tagline',
  url: process.env.DOCS_URL || 'https://my-docs.someurl',
etc...

and I noticed that docusaurus.config.js appears to load twice, resulting in the following console output...

$ npm run build

> docs-website@0.0.0 build
> docusaurus build

process.env.NODE_ENV is:  undefined
[INFO] [en] Creating an optimized production build...
process.env.NODE_ENV is:  production

✔ Client
  

✔ Server
  Compiled successfully in 18.64s


✔ Client
  

● Server █████████████████████████ cache (99%) shutdown IdleFileCachePlugin
 stored

[SUCCESS] Generated static files in "build".
[INFO] Use `npm run serve` command to test your build locally.

So it looks like the first time through, process.env.NODE_ENV isn't set, which result in an error in node_modules\@docusaurus\core\lib\server\configValidation.js i.e. [ERROR] Error: "url" is required if you only rely on dotenv config alone, without the fallback as per my second attempt

Do you think this is a bug worth reporting?