Re: debian.org Language Subdomain Proposal

On Tue, Jul 30, 2019 at 1:47 PM Paul Wise wrote:

> Passing cookies for this could work easily, but discussing it a while
> ago we decided there could be GDPR issues. I seem to remember I worked
> out that via some Apache rewrite rules it would be possible to use the
> names of top-level directories to influence content negotiation, but I
> neglected to take notes about how.

It looks like we just need to set the prefer-language Apache variable
and it looks like there is a way to do that based on the domain,
subdirectory, cookies or almost anything else we could think of.

https://httpd.apache.org/docs/current/content-negotiation.html#exceptions
https://httpd.apache.org/docs/2.4/mod/mod_setenvif.html#setenvif
https://httpd.apache.org/docs/current/mod/mod_rewrite.html#rewriterule

So, assuming the web server filesystem has no directories matching any
language code, something like this should do the job (untested):

RewriteEngine  on
RewriteRule "^/[a-z][a-z](/.*)"  "/$1" [passthrough]
RewriteRule "^/[a-z][a-z]-[a-z][a-z](/.*)"  "/$1" [passthrough]
SetEnvIf Request_URI "^/([a-z][a-z])/" prefer-language=$1
SetEnvIf Request_URI "^/([a-z][a-z]-[a-z][a-z])/" prefer-language=$1

I'll have a look at testing this when I get time, then we can decide
what method we want to use for sticky links and update the translation
selection mechanism to use it.