How to have nginx proxy_pass follow upstream 302 redirects (eg, when you're running a steam cache and you're behind Cox's layer 7 interception stuff)

proxy.conf

# This config came around after a friend had problems with a Steam cache on his
# Cox internet connection. Cox would intercept any requests to Steam content
# servers and return a 302 to Cox's servers. The cache would return the 302
# to the Steam client, and the Steam client would go directly to Cox, bypassing
# the cache.
# This config makes nginx follow the 302 itself, and caches the result of the
# redirect as if it was the response to the original request. So subsequent
# requests to the URL that returned a 302 will get the file instead of a 302.


proxy_cache_path /cache keys_zone=steam:100m levels=1:2 inactive=100d max_size=1000g;

server {
    listen      80;
    charset     utf-8;

    client_max_body_size 75M;

    # main cache block - when upstream responds with a 302, it's caught by 
    # error_page and passed off to the (nearly identical) @handle_redirects
    location / {
       proxy_pass http://web;
       proxy_cache       steam;
       proxy_cache_key   $uri;
       proxy_cache_valid 200 206 3000h;
       proxy_intercept_errors on;
       error_page 301 302 307 = @handle_redirects;
    }

    location @handle_redirects {
       #store the current state of the world so we can reuse it in a minute
       # We need to capture these values now, because as soon as we invoke 
       # the proxy_* directives, these will disappear
       set $original_uri $uri;
       set $orig_loc $upstream_http_location;

       # nginx goes to fetch the value from the upstream Location header
       proxy_pass $orig_loc;
       proxy_cache       steam;
       # But we store the result with the cache key of the original request URI
       # so that future clients don't need to follow the redirect too
       proxy_cache_key $original_uri;
       proxy_cache_valid 200 206 3000h;
    }
}

Thank you for the gist. In my case (running as a Docker container) I would get an error about not being able to resolve. For some reason proxy_pass with a replacement variable ($orig_loc) triggers a resolve which fails when run inside Docker. Adding

# adding Google DNS resolver
resolver 8.8.8.8;

inside the location @handle_redirects { section fixed the problem.

Some troubleshooting notes while trying to proxy services.gradle.org (and locally cache requested binaries):

• Had to ignore a lot of headers or nothing gets cached. Also, failing to ignore these headers would cause a 500 on the second request ($upstream_http_location was "").
• Had to change the cache key or I got internal server errors
• Added stale config (I want this to be the equivalent of a local copy)
• Had to add a DNS server like @ypujante
• Note: I'm using a different cache name.

Main

proxy_cache_path /data/cache levels=1:2 keys_zone=my_cache:10m max_size=60g inactive=100000m use_temp_path=off;

Server:

client_max_body_size 300M; 
                             
location /test/gradle/ {
  proxy_cache my_cache;                                                           
  proxy_pass https://services.gradle.org/distributions/;                                       
  proxy_cache_key $scheme$proxy_host$uri;
  proxy_cache_valid 200 206 3000h;
  proxy_cache_use_stale  error timeout invalid_header updating
     http_500 http_502 http_503 http_504;                                                       
  proxy_intercept_errors on;
  error_page 301 302 307 = @handle_redirects;      
                                                                                                
  proxy_ignore_headers Set-Cookie;
  proxy_ignore_headers Cache-Control;
  proxy_ignore_headers Expires;
  proxy_hide_header Set-Cookie;      
  proxy_hide_header Cache-Control;     
  proxy_hide_header Expires;      
}   

location @handle_redirects {
   #store the current state of the world so we can reuse it in a minute
   # We need to capture these values now, because as soon as we invoke 
   # the proxy_* directives, these will disappear
   set $original_uri $uri;
   set $orig_loc $upstream_http_location;

   # nginx goes to fetch the value from the upstream Location header
   proxy_pass $orig_loc;
   proxy_cache       my_cache;
   # But we store the result with the cache key of the original request URI
   # so that future clients don't need to follow the redirect too
   proxy_cache_key $original_uri;
   proxy_cache_valid 200 206 3000h;
   proxy_cache_use_stale  error timeout invalid_header updating
     http_500 http_502 http_503 http_504;                 

  resolver 8.8.8.8; # Seems to be needed for redirects.
  proxy_ignore_headers Set-Cookie;
  proxy_ignore_headers Cache-Control;
  proxy_ignore_headers Expires;
  proxy_hide_header Set-Cookie;
  proxy_hide_header Cache-Control;
  proxy_hide_header Expires;
}

Thank you, this forks fine.

I had to add resolver directive to @handle_redirects location like @ypujante, otherwise I had "no resolver defined" error.

Hi. I made a load balancer using Upstream. as follows.

*
*
*
   upstream appservers {
	least_conn;
        server srv1.domain.com:443;
        server srv2.domain.com:443;
    }
*
*
*
    server {
        listen 443 ssl http2;

        server_name domain.com:443;

        location /hls {	
		proxy_pass https://appservers/hls;
         }
    }
*
*
*

I set nginx.conf similar to above.

It's working fine now, but the main server domain.com:443 is heavily affected by live streams. How can I 302 forward this traffic to the edge servers?

So I want to direct every incoming request as a link to the end servers.

domain.com/hls/test.m3u8 > srv1.domain.com/hls/test.m3u8
domain.com/hls/test.m3u8 > srv2.domain.com/hls/test.m3u8
*
*
As. I want to distribute live streams to upstream servers.

Thanks.

@stopperbir Hello, did you find any solution for this?

@Zonimi Unfortunately I still haven't found it. I tried many things but it doesn't work.

This gist got me 90% of the way there, but somehow the redirect was still being cached, I think. The suggestion of adding

  proxy_ignore_headers Set-Cookie;
  proxy_ignore_headers Cache-Control;

after error_page 301 302 307 = @handle_redirect; has worked for me. I tried to use proxy_no_cache $http_location, proxy_no_cache $sent_http_location or proxy_no_cache $upstream_http_location to prevent the redirect itself from being cached, but that statement was apparently being ignored. I would love to understand why this is needed but I don't know how to start debugging it.