process.env.DOCUSAURUS_CURRENT_LOCALE is undefined in serve

[Josh-Cena]

Discussed in #8848

^{Originally posted by laojun March 30, 2023}
Hi:
First of all, Thanks for the v2.4。

I use process.env.DOCUSAURUS_CURRENT_LOCALE to solve my problem in https://github.com/facebook/docusaurus/discussions/8745。

Here is my docusaurus.config.js

baseUrl: `/${process.env.DOCUSAURUS_CURRENT_LOCALE}/`

Seems right when i run build

But error when i run server

How can i make it right when i run server?

Thanks

[slorber]

@laojun according to you, which value process.env.DOCUSAURUS_CURRENT_LOCALE should have when running the serve command?

The original PR (#8677) mentions that this env variable is a temporary workaround until we figure out a better API

And it is also explained that you have to program defensively against the value being potentially undefined.

docusaurus serve belongs to the commands we documented as having an undefined current locale env variable.

My suggestion, try something like this:

baseUrl: process.env.DOCUSAURUS_CURRENT_LOCALE
  ? `/${process.env.DOCUSAURUS_CURRENT_LOCALE}/`
  : "/"; // or "/zh-cn/" ???

---

Going to close because for me it's not a bug, it's a documented limitation of the current implementation.

Even if we had a better API, I have no idea which locale we should define as the "current one" when running docusaurus serve. I'm not sure we could generalize a good solution here. There are many cases to consider when serving a build output depending on what has been built (single localized site vs site with multiple locales built one after the other)

Open to discussing this more but please explain me your expectations when running this command.

[Josh-Cena]

Yeah, that makes sense :/ Multiple locales are served at once so it's hard to tell

[laojun]

@laojun according to you, which value process.env.DOCUSAURUS_CURRENT_LOCALE should have when running the serve command?

The original PR (#8677) mentions that this env variable is a temporary workaround until we figure out a better API

And it is also explained that you have to program defensively against the value being potentially undefined.

docusaurus serve belongs to the commands we documented as having an undefined current locale env variable.

My suggestion, try something like this:

baseUrl: process.env.DOCUSAURUS_CURRENT_LOCALE
  ? `/${process.env.DOCUSAURUS_CURRENT_LOCALE}/`
  : "/"; // or "/zh-cn/" ???

Going to close because for me it's not a bug, it's a documented limitation of the current implementation.

Even if we had a better API, I have no idea which locale we should define as the "current one" when running docusaurus serve. I'm not sure we could generalize a good solution here. There are many cases to consider when serving a build output depending on what has been built (single localized site vs site with multiple locales built one after the other)

Open to discussing this more but please explain me your expectations when running this command.

Thanks for the reply。

I try it like this

baseUrl: process.env.DOCUSAURUS_CURRENT_LOCALE ? `/${process.env.DOCUSAURUS_CURRENT_LOCALE}/` : '/zh-cn/',

It goes well when i choose locale zh-cn, And the url goes to /zh-cn/en-us when i chose en-us, The url should be /en-us.

[slorber]

It goes well when i choose locale zh-cn, And the url goes to /zh-cn/en-us when i chose en-us, The url should be /en-us.

That's probably a bug in the locale dropdown. Can you open another dedicated issue and provide a repro we can look at?

[Josh-Cena]

This is the same issue as #8652 I believe

This is working as intended. We don't support two locales both having base URLs—one must be the default and not have any base URL. When you choose /zh-cn/ as the site's base URL, this means zh-CN docs actually have base URL /zh-cn/ + / = /zh-cn/, and en-US has base URL /zh-cn/ + /en-us/ = /zh-cn/en-us/.

[slorber]

I think we could fix this behavior as part of #6731

This means you could keep / for your site baseUrl, but make Docusaurus use /zh-cn/ for the default locale instead of /

/ + /zh-cn/ = /zh-cn/

Does it make sense?