https://github.com/ClockworkNet/wtop might be a option

The default value for "log_format" is "combined" -- identical to the Apache "combined" log format -- so apachetop can read nginx log files without any needed changes.

GoAccess is awesome, free and open source console based. It may output an HTML, JSON, CSV report too.

http://goaccess.prosoftcorp.com/

apachetop works fine with nginx logs too.