Rewrite rule for reverse proxy

[Claude]

Igor Sysoev <is at ...> writes:

> 
> On Tue, May 12, 2009 at 03:58:31AM +0000, Claude wrote:
> 
> > Trying to write a rewrite rule that will transform this url 
> > http://external_site.com/login?back_url=http%3A%2F%2Finternal_url%2F 
> > to this one 
> > http://external_site.com/login?back_url=http%3A%2F%2Fexternal_site.com%2F
> > 
> > I know I need to play with arguments and rewrite but I'm stuck. 
> 
> Redirection rewrite capabilitires are very limited: they works with
> exact strings only, but you may try
> 
>   proxy_redirect  default;
> 
>   proxy_redirect
>      http://external_site.com/login?back_url=http%3A%2F%2Finternal_url%2F
>      http://external_site.com/login?back_url=http%3A%2F%2Fexternal_site.com%2F
>   ;
> 

Hum, not exactly what I'm looking for as I don't know in advance how many pages
will use the string "internal_site" and also the parameter can be something
else. It would be nice to have something similar to the substitution module for
uri...