Scenario: "Depok": Nginx with Brotli

Level: Medium

Type: Fix

Tags: nginx  

Description: You are tasked to add compression to the company website. The website is running on an Nginx server, and you decide to add Brotli compression to it.

Brotli has became very popular these days because of its high compression ratio. It's a generic-purpose lossless compression algorithm that compresses data using a combination of a modern variant of the LZ77 algorithm, Huffman coding, and 2nd order context modeling.

For this purpose, you decided to compile the brotli modules yourself and add them to the Nginx server.

The location of the Brotli source code is at /home/admin/ngx_brotli. The nginx source code (needed to compile the modules) is located at /home/admin/nginx-1.18.0. From the ngx_brotli repository first you need to compile the brotli dependencies and then configure and make modules for Nginx. Afer that you need to add the modules to the Nginx configuration.

After installing the modules, you need to make sure the responses from the server are being server with compression.

Create a port-forward to port 80 from the server to your computer and check the header Content-Encoding, responses must return br for Brotli compression. You can also use curl -H "Accept-Encoding: br, gzip" -I http://localhost to check the header.

Something nice about Brotli is that it fails over to gzip if the client doesn't support Brotli, so curl -H "Accept-Encoding: gzip" -I http://localhost should return gzip instead.

Test: curl -H "Accept-Encoding: br" -sI http://localhost returns the header Content-Encoding: br.

The "Check My Solution" button runs the script _/home/admin/agent/check.sh_, which you can see and execute.

Time to Solve: 15 minutes.