Logstash Unable to parse dot inside a json

Elastic Stack Logstash
1

I am trying to parse my CSV fomatted logs using logstash. I am facing problem in parsing a json which contains dot(.) in the key of json.

I took reference from this link ref but didn't work for me

My sample input is

2016-10-17 10:44:37,733|null|{"k1.k2.k3.k4":"val"}|{"requestId":"9s,ss4"}|{"status":"PG601"}|1732|{"testKey": "<?xml version="}

My filter code is :

filter {
ruby {
code => "
event.to_hash.keys.each { |k| event[ k.sub('.','_') ] = event.remove(k) if k.include?'.' }
"
}

    mutate {                gsub => ["message","\"","'"]        }
    csv {
            columns => ["TIMESTAMP","URI","HEADERS","REQUEST","RESPONSE","RESPONSE_TIME","INTER_RESPONSE"]
            separator => "|"
    }
    mutate {
            add_field => { "INDEX_NAME" => "pg_request_response" }
    }
    mutate { gsub => ["REQUEST", "'", '"']}
    json {             source => "REQUEST"    target => "request"  }

    mutate { gsub => ["RESPONSE", "'", '"']}
    json {             source => "RESPONSE"      target => "response"    }

    mutate { gsub => ["HEADERS", "'", '"']}
    json {             source => "HEADERS"     target => "headers"   }
     mutate { gsub => ["INTER_RESPONSE", "'", '"']   }
    json {             source => "INTER_RESPONSE"    }
    #date { match => ["TIMESTAMP", "YYYY-MM-dd HH:mm:ss,SSS"]        }

}

2

I took reference from this link ref but didn't work for me

Please be more specific. And what's wrong with the de_dot filter?