Use nested field names in Grok custom patterns

[vilman]

Hi,

I'm trying to map a nested field from a custom grok expression.

So, instead of using:
(?=.*?Message Type: (?<test1>[^;]+))?

I would like to map test1 to [event][name].

Tried things like:

(?=.*?Message Type: (?<[event][name]>[^;]+))?
(?=.*?Message Type: (?<event.name>[^;]+))?
(?=.*?Message Type: (?<{[event][name]}>[^;]+))?
...

Is that even possible? I know I could rename them later but that's not the idea...

Thanks!

[vilman]

This seems related to a support library issue. Can't be fixed at least 3y ago. An option would be to define custom patterns.

See Parse regex to a nested field · Issue #66 · logstash-plugins/logstash-filter-grok · GitHub.