Force interface language by config file #792

As explained in #785, trying to force the language interface which specified in .env file.

I tried the commented code below and re-compiled the front, but nothing happened. Since I didn't find any other piece which gets browser language, I assume my method of recompilation is flawed. (Only do cargo web deploy -p plume-front --release)

So I made this WIP PR as @igalic suggested. 😁

Codecov Report

Merging #792 into master will decrease coverage by 0.01%.
The diff coverage is n/a.

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The issue with the front-end is that it runs in the browser: it can't access the environment variables of the server.

I think the solution would be to:

first, do this change on the server side, where you can access the environment variables from the configuration. This may require you to change Plume-org/rocket-i18n first
then, once this settings works on the server, add a lang property to every <html> tag we render, containing the language code that we chose to render the page
in the front-end, use this lang attribute to detect the language instead of relying on navigator.language as we currently do.

I hope this isn't too much. I can try to guide you more if need detailed steps, I know it can be hard to get started on a codebase you know nothing about. Feel free to ask me here or on Matrix if you have any questions.

I assume my method of recompilation is flawed. (Only do cargo web deploy -p plume-front --release)

The feature is missing, so it's not the issue at hand, but doing just that was actually not sufficient. You must also rebuild Plume, as it's build script (build.rs) is the one copying files from target/ to where static files should be

I give up on this. Could not make it work...