How to implement redirect depending on header and path?

Question

Nginx

I need a redirect to a particular url depending on the path and title (or rather the OS in the title).
For example, /search redirects to yandex from an iPhone and to google from an android.
How can this be implemented?

Answer 1

Make conditions with regular expressions that bypass the corresponding heading. But in general, this is not the most kosher way to use nginx - usually such logic is left inside the application.

Answer 2

I think map will help, https://nginx.org/en/docs/http/ngx_http_map_module.html
Substituting one value based on another is exactly what it is.