Key=value extractor and quotes / remove whitespaces with regex and replace

Graylog Central (peer support)
8

a processing rule would look like:

rule "kv_ex_prefix"
when
    has_field("kv")
then
    // extract all key-value from "message" and prefix it with kv_ 
    set_fields(
                fields: 
                        key_value(
                            value: to_string($message.message), 
                            trim_value_chars: "\""
                            ),
                prefix: "kv_"
            );

end

This would also strip out the " if present.