Learning nginx

Until today I was just a copy+paster of nginx configs. I thought I had my share back when I learned and undestood apache very well, so why learn another one. But my nextcloud setup and letsencrypt that comes with it has an nginx "bundled", so I would like to understand things a bit better. So I started reading the docs and will take my notes here.

Open Source Or Not?

I been surfing and reading on nginx.com which didn't feel very open sourcy and always mentioned "NGINX Plus", where I felt I have to go and buy it, which was the intention, I guess. But I did find nginx.org and reading the about nginx I also got the confirmation for my feelings, there is the open source universe and the commercial universe for nginx. Very cool, I love it when open source can be made sustainable by having those that can/want/should do pay for the software. Sounds like another open source based business at work, awesome!

Notes on server, server_name and location

• The first server block (as the docs name it), looking like this server {, is the default server, used when none below matches
• Search Priorities is always 1) exact name 2) wildcards 3) regular expressions this seems to be that case for server_name and location which I only found explained very much in detail on nginx.com
• Location search priorities are also explained using examples here
• "locations of all types test only a URI part of request line without arguments" which means query params can NOT be used for filtering for a location, sounds reasonable since that might end in hell
• location / { matches any request and it will be used as a last resort
• regular expressions are PCRE, Perl regular expressions, details for usage in nginx are here
• The strange server_name _ as I found in my nextcloud nginx, is explained here too

  There is nothing special about this name, it is just one of a myriad of invalid domain names which never intersect with any real name. Other invalid names like “--” and “!@#” may equally be used.