Proxy-set-header: Forwarding HTTP headers from Nginx to a WordPress container

I detailed in a recent post how I got a working WordPress container setup, complete with database and PHP engine. I saved the bit about how to redirect traffic to the container (and apply encryption to the outbound connections) because I knew it was going to be just as much work as getting the setup running. Also I needed to first get up to speed on HTTP headers in general and how to inspect them specifically.

This post is not a how-to any more than it’s a how-not-to. I wanted to detail as much the attempts that did not work as the final one that did because the former were just as illuminating as the latter.