Logstash config version

Hello.
What is the best way to set logstash config version?
When i change config for my custom log source, i must change index name and so on.
So, is it some @metadata field, that i can use for setting config version, and set index name like when i do it for beats?
%{[@metadata][beat]}-%{[@metadata][version]}-%{+YYYY.MM.dd}

Can you provide an example how to do it?