Proxy Caching in the ngx_http_proxy_module in Nginx

The ngx_http_proxy_module is one of the essential components of Nginx, allowing us to forward HTTP requests to other servers. One of the notable features of this module is its ability to use caching. Caching requests helps us reduce the load on servers, resulting in faster website response times.

This module allows us to define which HTTP requests should be cached. For instance, we can specify which requests should be cached and which should not. This capability gives us more control over server performance and resource usage.

Using the proxy_cache_methods directive, we can define these methods. This directive allows us to specify which HTTP methods should be cached. By default, only GET and HEAD requests are cached, but with this directive, we can add other methods as well.

For example, let's assume we want to cache POST requests too. We can easily do this by specifying the methods in the proxy_cache_methods directive. This capability is particularly useful for applications that heavily depend on caching.

location /api {
    proxy_pass http://backend;
    proxy_cache my_cache;
    proxy_cache_methods GET HEAD POST;
}

In the above code, we define a location block for requests to the address /api. Initially, by using the proxy_pass directive, requests are forwarded to the server backend. Then, using proxy_cache, caching is enabled, and we specify the requests to be cached: GET, HEAD, and POST.

Code Explanation: