Suppor for referencing nested record fields in Fluent plugin

[Horkyze]

Currently, there is no way (that I know of) to reference nested JSON items in fluents plugin.

Somthing like this:

label_keys container_tag, hostname, message['path'], massage.path

It would be awesome to have the ability to use Fluent's RecordAccessor module.

So the nested items will be accessible like this:

label_keys container_tag, hostname, $.message.method,  $.message.anyting

The whole problem can be avoided I one does not uses nested JSONs in their record data model. But on the other hand, nesting provides better readability.

[cyriltovena]

This is only true for fluentd, for fluent-bit we have nested mapping via json config.

This is very interesting, thank you !

[slim-bean]

This looks like it's supported now as of #1186