Dynamic Proxy Pass - is there a more elegant solution?

I’m X-Accel-Redirecting URLs that look like:


Right now my location that handles these and requests from S3 looks like

location ~ /AWSS3/(.*) {

Store our ETag value.

set $rails_etag $upstream_http_etag;

Prevent Amazon from overwriting our Headers.

proxy_hide_header Content-Type;
proxy_hide_header ETag;

Hide Amazon Headers

proxy_hide_header X-Amz-Id-2;
proxy_hide_header X-Amz-Request-Id;

Set the HTTP Host header to S3.

proxy_set_header Host ‘s3.amazonaws.com’;

Force Amazon to do the heavy lifting.

proxy_max_temp_file_size 0;

Ensure tight timeouts, we’ll retry the requests to a different

backend in

the event of failures.

proxy_connect_timeout 5;
proxy_send_timeout 10;
proxy_read_timeout 10;

Retry if Amazon freaks out.

proxy_next_upstream error timeout http_500 http_502 http_503 http_504;

Ensure the requests are always gets.

proxy_method GET;
proxy_set_header Method ‘GET’;
proxy_set_header Content-Length “”;
proxy_set_header Cookie “”;
proxy_set_header Content-Type “”;

Clear any CloudFront headers.

proxy_set_header X-Amz-Cf-Id “”;

We use the query string for Authorization, clear headers that the


may have sent.

proxy_set_header Authorization “”;

Resolver, for dynamically proxied requests.


Proxy to S3.

set $s3 “s3-external-2.amazonaws.com”;
proxy_pass https://$s3/$1$is_args$args;

Add back our own ETag.

add_header ETag $rails_etag;


Is there a way to avoid having to capture the path in the location
block and reconstruct it with $is_args$args?

I would like something more like:

location /AWSS3/ {

proxy_pass https://$s3/;

which does work when passing to an upstream block (https://s3/ with
upstream s3 defined).

I prefer this method as it re-resolves the DNS periodically.