Micro-caching for dynamic content in Nginx - Mini Project: Build & Apply

Micro-caching for dynamic content

📖 Scenario: You manage a busy website that serves dynamic content. To improve speed and reduce server load, you want to add a short cache (micro-cache) for dynamic pages using nginx. This cache will store responses for a few seconds so repeated requests are faster.

🎯 Goal: Set up a micro-cache in nginx that caches dynamic content for 5 seconds. You will create the cache zone, configure caching rules, and verify the cache works by printing cache status headers.

📋 What You'll Learn

Create an nginx cache zone named microcache with 10MB size

Set cache key to $scheme$host$request_uri

Cache dynamic content for 5 seconds

Add headers to show cache status

Test caching by printing cache status header

💡 Why This Matters

🌍 Real World

Micro-caching helps busy websites serve dynamic content faster by temporarily storing responses. This reduces server load and improves user experience.

💼 Career

DevOps engineers often configure nginx caching to optimize web performance and scalability in production environments.

1

Create the cache zone

In the http block of your nginx config, create a cache zone named microcache with 10MB size using proxy_cache_path. Use /tmp/nginx_microcache as the cache directory.

Nginx

# Your code here

Need a hint?

Use proxy_cache_path directive inside http block to define cache zone.

2

Configure cache key and enable micro-caching

Inside the server block, set proxy_cache to microcache and define proxy_cache_key as $scheme$host$request_uri. Set proxy_cache_valid to cache 200 responses for 5 seconds.

Nginx

http {
    proxy_cache_path /tmp/nginx_microcache levels=1:2 keys_zone=microcache:10m max_size=10m inactive=60m use_temp_path=off;
}

server {
    listen 80;
    server_name example.com;
    # Your code here
}

Need a hint?

Use proxy_cache, proxy_cache_key, and proxy_cache_valid directives inside server block.

3

Add headers to show cache status

Inside the location / block, add proxy_pass to http://backend. Add add_header directives to show X-Cache-Status header with $upstream_cache_status value.

Nginx

http {
    proxy_cache_path /tmp/nginx_microcache levels=1:2 keys_zone=microcache:10m max_size=10m inactive=60m use_temp_path=off;
}

server {
    listen 80;
    server_name example.com;

    proxy_cache microcache;
    proxy_cache_key "$scheme$host$request_uri";
    proxy_cache_valid 200 5s;

    # Your code here
}

Need a hint?

Use location / block with proxy_pass and add_header directives.

4

Test and print cache status header

Run curl -i http://localhost/ to see the X-Cache-Status header in the response. This shows if the response was served from cache.

Nginx

http {
    proxy_cache_path /tmp/nginx_microcache levels=1:2 keys_zone=microcache:10m max_size=10m inactive=60m use_temp_path=off;
}

server {
    listen 80;
    server_name example.com;

    proxy_cache microcache;
    proxy_cache_key "$scheme$host$request_uri";
    proxy_cache_valid 200 5s;

    location / {
        proxy_pass http://backend;
        add_header X-Cache-Status $upstream_cache_status;
    }
}

# Your code here

Need a hint?

Use curl -i http://localhost/ to see headers including X-Cache-Status.