best way to debug nginx rewrite rules in config file?
Enable rewrite_log:
rewrite_log on;
and set debug level in error_log directive:
error_log /var/log/nginx/localhost.error_log notice;
Enable debugging support, then set debug level in error_log.
error_log /var/log/nginx/error.log debug;
Now you can tail the log and send your requests through. There's probably more detail than you want, but that can sometimes be a lifesaver.
Oh, and you should be aware that if is evil, in a location context at least...