Redirect from default language should be permanent

[max-frai]

Description

For seo-correctness when we want to skip default language we should do a redirect to page without mentioned page language:

site.com/en/page -> site.com/page
site.com/de/page -> site.com/de/page

next-intl/packages/next-intl/src/middleware/middleware.tsx

Line 106 in b5884a7

return NextResponse.redirect(urlObj.toString());

In middleware redirect function you have:
return NextResponse.redirect(urlObj.toString());

It produces 307 code which is "temporarily" redirect. This is not good for seo purposes, because google crawler will follow this redirect each time and each redirect chain decrease number of requests per day allowed for a site.

Solution is:
return NextResponse.redirect(urlObj.toString(), { status: 308 });

This way google won't remember and follow redirect for default locale each time.

Mandatory reproduction URL (CodeSandbox or GitHub repository)

https://next-intl-example-next-13.vercel.app/en

Reproduction description

https://next-intl-example-next-13.vercel.app/en

Expected behaviour

https://next-intl-example-next-13.vercel.app/en this page should redirect to https://next-intl-example-next-13.vercel.app/ with 308 status code, not 307

[amannn]

There's some nuance to this, as the next-intl middleware definitely needs to use temporary redirects.

I guess it's up to debate if the use case of redirecting /en to / for defaultLocale: 'en' and localePrefix: 'as-necessary' could be permanent.

Note that in the upcoming 3.0 release we're switching the default for localePrefix to always (as-necessary remains supported though). Among other topics, the question about the status code of this redirect also vanishes with localePrefix: 'always'. I'd generally recommend moving to that routing strategy.

However, let's go back to the topic:

because google crawler will follow this redirect each time

Where does the Google Crawler pick up the /en route in the first place? It's mostly there for compatibility, but / is the target of the redirect and the Link header also describes this route to be used for users that prefer the en locale:

Link: <https://next-intl-example-next-13.vercel.app/>; rel="alternate"; hreflang="en",
      <https://next-intl-example-next-13.vercel.app/de>; rel="alternate"; hreflang="de",
      <https://next-intl-example-next-13.vercel.app/>; rel="alternate"; hreflang="x-default"

E.g. when building a sitemap, you should consider linking to / instead of /en.

[amannn]

Closing this due to inactivity …

[RicSala]

i agree that it should be a permanent redirect. Otherwise Google keeps going there..