Logstash不解析JSON，运行时不显示

Question

我是Logstash的新手，我正在使用Logstash解析JSON行，如下所示：

{"timestamp":"1970-01-01T08:00:11.328750+0800","flow_id":666385651532846,"pcap_cnt":19,"event_type":"dns","src_ip":"10.0.2.28","src_port":62793,"dest_ip":"8.8.8.8","dest_port":53,"proto":"UDP","dns":{"type":"query","id":52369,"rrname":"dns.msftncsi.com","rrtype":"A","tx_id":0}}

我在这里使用我的配置，但未显示任何内容：

input { 
   file {
    type => "json"
    path => "/home/sfrogit96/Documents/ELK/logstash-6.3.1/bin/test.json"
    start_position => "beginning"
  }
}  

filter {
  json {
    source => "message"
    target => "message"
  }


}
 output { stdout { codec => rubydebug  }}