Preserve base URL when loading assets on proxied web page - html

Question

I'm trying to host a site (called site1) nested within an existing domain (www.gateway.com).
e.g. Instead of www.site1.com/profile, it would be www.gateway.com/site1/profile.
I have an NGINX reverse proxy that detects the /site1/ path and proxies it to some upstream machines:
location ~/site1/(.*)$ {
proxy_pass http://upstreams/$1$is_args$args;
proxy_set_header Host $host;
}
The proxy itself is working fine - it redirects all the paths correctly. However, the site's assets (e.g. JS, CSS, etc.) do not preserve the base path (www.gateway.com/site1).
e.g. It is trying to load www.gateway.com/normalize.css, when the actual asset lives at www.gateway.com/site1/normalize.css.
For reference, the HTML for site1 is sourcing assets like so:
<link href="/normalize.css" rel="stylesheet" />
I've also tried removing the leading / in the href, but this results in the asset's path including the full route (less the last fragment) - also not what is desired.
Note that site1 works fine when hosted at the root of a domain (e.g. www.gateway.com/profile).
Any insights would be helpful. Thanks!

Answer 1

You might already have a block that checks for static fields that is messing up your asset delivery. To me what you are doing seems fine, but you have other nginx asset code possibly either on the upstream or site1 messit up. Add a block that checks for static files. If you are only doing this for one or two sites, this is reasonable.
The code below should work until you get us more info on other asset code.
location ~/site1/(.*)$ {
location ~* \.(?:js|css|jpg|jpeg|gif|png|ico|cur|svg)$ {
alias /location/of/site1;
expires 1M;
access_log off;
sendfile on;
sendfile_max_chunk 1m;
add_header Cache-Control public;
}
location ~* {
try_files $uri #nonStatic;
}
}
location #nonStatic {
proxy_pass http://upstreams/$1$is_args$args;
proxy_set_header Host $host;
}