我的日志有两个数据源。一个是beat，一个是kafka，我想基于源代码创建es索引。if kafka->在索引名前面加上kafka，if beat在索引名前面加上beat。

input {
  beats {
    port => 9300
  }
}

input {
  kafka {
    bootstrap_servers => "localhost:9092"
    topics => ["my-topic"]
    codec => json
  }
}

output {
    # if kafka
      elasticsearch {
        hosts => "http://localhost:9200"
        user => "elastic"
        password => "password"
        index  => "[kafka-topic]-my-index"
     }
    # else if beat
    elasticsearch {
        hosts => "http://localhost:9200"
        user => "elastic"
        password => "password"
        index  => "[filebeat]-my-index"
     }
}