proxying relative urls with nginx

nginx, proxy, reverse-proxy, webserver

Solution

Based on your updated comments; if the upstream backend sends the referer header, you could do something like this:

location ~* ^/(css|js)/.+\.(css|js)$ {            
        #checking if referer is from app1            
        if ($http_referer ~ "^.*/app1"){
            return 417;
        }    

        #checking if referer is from app2
        if ($http_referer ~ "^.*/app2"){
            return 418;
        }    
    }
    error_page   417  /app1$request_uri;
    error_page   418  /app2$request_uri;


    location /app1 {        
         proxy_pass  http://app1.com;
    }

    location /app2 {
        proxy_pass http://app2.com;
    }

For example, if the backend on app2.com, requests the test.css like this:

curl 'http://example.com/css/test.css' -H 'Referer: http://app2.com/app2/some/api'

The request land here:

/app2/css/test.css

Problem

My question is similar to Nginx Relative URL to Absolute Rewrite Rule? - but with an added twist. I have nginx acting as a proxy server, which proxies for multiple apps, similar to this (simplified) config: ``` server { listen 80; server_name example.com; location /app1 { proxy_pass http://app1.com; } location /app2 { proxy_pass http://app2.com; } } ``` This works fine, but as in the other question, these applications (`app1` and `app2`) use relative urls such as `/css/foo.css`, or `/js/bar.js`. Also it's a big problem to ask all applications to change to something like `/app1/css/foo.css`. Is it possible for nginx to intelligently figure out which application should handle the request? FTR, users would be accessing these applications like this: `http://example.com/app1/fooaction` or `http://example.com/app2/baraction`. If it matters, all applications are Java/Tomcat based apps. TIA!

Original source