我需要防止某些字段的值像“null”（null作为字符串）和 "" （空字符串）从elasticsearch中获取索引，即，我应该能够获取在源字段中不包含这些字段的文档。
索引时Map中是否需要任何设置，例如在字段上使用自定义分析器？
p、 s:-我正在使用elasticsearch 7.6.1
我试过下面的答案，这就是为什么它不起作用-

{  "settings": {
"number_of_shards": "5",
"analysis": {
  "normalizer": {
    "my_normalizer": {
      "char_filter": [
        {
          "type": "mapping",
          "mappings": [
            "null =>",
            "\"\"\" =>"
          ]
        }
      ],
      "filter": [
        "uppercase"
      ],
      "type": "custom"
    }
  }
},
"number_of_replicas": "1"}}

响应错误-序列化设置中只允许值列表
即使我尝试了以下设置，也没有得到预期的结果：

{  "settings": {
"number_of_shards": "5",
"analysis": {
  "char_filter": {
    "my_filter": {
      "type": "mapping",
      "mappings": [
        "null =>",
        "\"\"\" =>"
      ]
    }
  },
  "normalizer": {
    "my_normalizer": {
      "char_filter": [
        "my_filter"
      ],
      "filter": [
        "uppercase"
      ],
      "type": "custom"
    }
  }
},
"number_of_replicas": "1"}}

请求-getindexname/\u分析

{"normalizer":"my_normalizer","text":"null"}

回应-

{
"tokens": [
    {
        "token": "",
        "start_offset": 4,
        "end_offset": 4,
        "type": "word",
        "position": 0
    }
]

}
预期React-

{
"tokens": []
}