Indexing Json file

Hi,

I'm trying to parse JSON file with logstash. In kibana I see the field "counters" of my JSON file like that :

What i'm interested in is to get the "tele" in the "sdn" attribute

I tried to do a conf file like that :

input {
beats {
port=> 5044
}
}
filter{
json {
source => "message"
}
split { field => "[counters]" }

if "tele" in [counters][sdn]{
mutate{add_field=>["VNFc", "tele"]
}
}
}
output{
elasticsearch
{
action => "index"
hosts => ["localhost:9200"]
index => "test-%{+YYYY.MM.dd}"
}stdout {}
}

Thanks a lot (i'm new to ELK :grimacing: )