Can I proxy_pass to a variable?

[Igor Sysoev]

On Mon, May 10, 2010 at 04:29:46PM +0800, 任晓磊 wrote:

> On Mon, May 10, 2010 at 2:07 PM, Igor Sysoev <igor at sysoev.ru> wrote:
> > You have to write:
> >
> >     proxy_pass http://$http_host$request_uri;
> >
> > Since 0.8.25 and 0.7.65, you may write:
> >
> >     proxy_pass http://$http_host;
> 
> But, why didn't I need to specify $request_uri when proxy_pass to a
> literal value?

For historical reasons.
There are two ways to map URI to a resource: root and alias:

     location /dir1/ {
         root  /path/to;
     }

     location /dir2/ {
         alias  /path/to/dir3/;
     }

The variables support has appeared eventually:

     location / {
         root  /path/$host;
     }

     location ~ ^/~(?<user>[^/]+)(?<path>.*)$ {
         alias  /homes/$user/$path;
     }

In proxy_pass the root way is:

     location /dir1/ {
         proxy_pass  http://host;
     }

The alias way is:

     location /dir2/ {
         proxy_pass  http://host/dir3/;
     }

The proxy_pass variables support has appeared to support proxying to a full
URL only as in static alias. Then the root way has been added.


-- 
Igor Sysoev
http://sysoev.ru/en/