Excellent write-up. I’ve got this working for my app now. A few words of caution for anyone else trying to set this up.
1.) Don’t copy and paste the code snippets. Type them all out manually. The double-quotes pasted into my IDE as fancy quotes and caused issues that I didn’t pick up on immediately. Same thing with the COPY — from line. The two hyphens pasted in as a single dash character and caused problems.
2.) Also on the COPY — from line, you’ll need to add a / to the end of /usr/share/nginx/html, otherwise docker will throw an error.