logstash yaml 插件

https://github.com/logstash-plugins/logstash-filter-yaml

该插件的基本逻辑为，指定一个列，将其通过 yaml 解析器解析为键值对，加到原来的 event 中。

filter {
    yaml {
        source => "extra_data"
        remove_field => [ "official_requirement", "extra_data" ]
    }
}