Header modification with NGINX

With more complexities in your system, sometimes some additional debug or information sent in the HTTP headers can be invaluable. The HTTP headers can have a specific meaning that tells the browser to treat a response a certain way or they could simply be to provide extra information, which can be used to trace specific issues from your website or applications.

Getting ready

The ability to modify the headers is already inbuilt into the NGINX core, but to use the latest features, you'll need version 1.10.0 or higher.

How to do it...

There are a number of different ways that we can modify the headers to suit different requirements. While the process remains the same for each, specific examples of where headers are commonly modified are detailed in the following examples.

Caching static content

For sites where the static media files (such as CSS, JS, and images) have a version number in their filename, we can easily cache the files with a long expiry without causing...