Mastering Nginx

Chapter 7

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• Any image will be cached for as long as possible, due to the images
  also being stored in the database, making it a truly expensive operation
  to retrieve them

We will configure NGINX to support this strategy as follows:

http {

# here we configure two separate shared memory zones for the keys/

metadata

# and filesystem paths for the cached objects themselves

proxy_cache_path /var/spool/nginx/articles keys_zone=ARTICLES:16m

levels=1:2 inactive=1d;

proxy_cache_path /var/spool/nginx/images keys_zone=IMAGES:128m

levels=1:2 inactive=30d;

# but both paths still lie on the same filesystem as proxy_temp_

path

proxy_temp_path /var/spool/nginx;

server {

location / {

# this is where the list of articles is found

proxy_cache_valid 1m;

}

location /articles {

# each article has a URI beginning with "/articles"

proxy_cache_valid 1d;

}

location /img {

# every image is referenced with a URI under "/img"

proxy_cache_valid 10y;

}

}

That takes care of our requirements. We have now activated caching for a legacy
application that has no caching support.