• Optimized Calibre-web Nginx reverse proxy config
• Calibre-Web Wiki reverse proxy setup instructions

This example would be even more helpful if it contained directives for location rewriting. For example, I am using the location /books/ in the proxy for calibre-web. Not being a web administation expert, it took me several hours to figure out how to make this work.

It looks like this:

location /books/ {
		proxy_pass http://127.0.0.1:8083;
		proxy_set_header Host $http_host;
		proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
		proxy_set_header X-Real-IP $remote_addr;
		proxy_set_header X-Scheme $scheme;
		proxy_set_header X-Script-Name /books;
		proxy_set_header X-Forwarded-Host $host;

		# Websockets settings
		proxy_http_version 1.1;
		proxy_set_header Upgrade $http_upgrade;

# The following line requires a "map" block outside the server block
#
# map $http_upgrade $connection_upgrade {
#    default upgrade;
#    ''      close;
# }
#
# A simple "Connection upgrade" may causes the login page (POST) to time out!

 		proxy_set_header Connection $connection_upgrade;
}

X-Script-Name is key here. I'd experimented with proxy_redirect and X-Forwarded-Prefix before, without success, and was about to give up, when I eventually found janeczku/calibre-web#19 which contained the hint to use X-Script-name.