feat(fetch): Add fallback languages configuration.

[Romakita]

fallbackLanguages give the possibility to configure a list of languages which must used the default language when a page is missing in the requested language.

Example

fallbackLanguages

• type: Array<string>

List of languages that will fallback to the default language when a page is request and didn't exists for the given local.

Example:

• try to fetch the page of /de/overview. If this page exists, it'll be displayed
• then try to fetch the default page /overview (depending on the default language). If this page exists, it'll be displayed
• then display 404 page.

window.$docsify = {
  fallbackLanguages: [
    "fr",
    "de"
  ]
};

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[Lalilu]

Hey guys, I don't understand how fallback languages works…

Can you guys explain me what I have to do to make it work in my instance?

Scenario (based on my assumption how it works):

/fr/documentA.md
/fr/documentB.md
/de/documentB.md

–> when I open /de/documentA, it gets redirected to /fr/documentA

Is that correct?

[gigaga]

Hello,

I don't understand too.

Currently, I have :

/fr/
/myDoc.md

with fallbackLanguages: ["fr"].

When I consult /myDoc it works, but when I try to go to /fr/myDoc I get a 404 error rather to redirect to /myDoc.

In fact, I think it is because I use basePath: "/src/" too :(

Thanks a lot