带状对象嵌套

Question

在Elasticsearch 6.3中，我试图在嵌套对象字段中应用bigram查询，该查询对象字段通过组合嵌套字段中的所有值来生成bigram数据。下面是映射。

 PUT /testindex
     {
     "settings": {
       "analysis": {
         "analyzer": {
              "my_shingles_test": {
                "tokenizer": "standard",
                "filter": [
                  "shingles"
                ]
              }
            },
            "filter": {
              "shingles": {
                "type": "shingle",
                "min_shingle_size": 2,
                "max_shingle_size": 3,
                "output_unigrams": false
              }
            }
          }
        },
    "mappings": {
    "default" :{
    "properties" : {
    "book_name":{
    "type":"text"
    },
    "book_id":{
    "type": "integer"
    },
    "book_attributes":{
    "type":"nested",
    "properties": {
    "search_term":{
    "type":"nested"
    "analyzer": "my_shingles_test"
    }
   }
  }
}

Here's the sample data:

        {
        "book_name":"xyz",
        "book_id":123,
        "book_attributes":[
        {
        "search_term":[
        "paperback"
        ]
        },
        {
        "search_term":[
        "best selling"
        ]
        }
        ]
        },
        {
        "book_name":"abc",
        "book_id":456,
        "book_attributes":[
        {
        "search_term":[
        "hardcover"
        ]
        },
        {
        "search_term":[
        "best author"
        ]
        },
        {
        "search_term":[
        "best selling"
        ]
        }
       ]
      }

在这里，我想为文档的所有搜索词创建bigram和trigram作为[平装本，最畅销，平装本最畅销]。当某人搜索平装书畅销书时，它应该只退回ID为123的书。我尝试过，但未返回预期结果。