ElasticSearch _suggest查询区分大小写。希望他们不区分大小写

我目前正在使用此端点和请求执行搜索：

elasticserver.com/citysuggest/_suggest -d {
  "result": {
    "text": "Chicago",
    "completion": {
      "field": "autoCompleteName"
    }
}

这是我的索引映射：

{
    "settings": {
        "number_of_shards": 1,
        "number_of_replicas": 1,
        "index": {
            "mapper": {
                "dynamic": false
            }
        },
        "analysis": {
            "analyzer": {
                "str_search_analyzer": {
                    "tokenizer": "standard",
                    "filter": ["standard", "str_delimiter", "asciifolding", "porter_stem"]
                },
                "str_index_analyzer": {
                    "tokenizer": "standard",
                    "filter": ["standard", "str_delimiter", "asciifolding", "porter_stem"],
                    "char_filter": "html_strip"
                }
            },
            "filter": {
                "str_delimiter": {
                    "type": "word_delimiter",
                    "generate_word_parts": true,
                    "catenate_words": true,
                    "catenate_numbers": true,
                    "catenate_all": true,
                    "split_on_case_change": true,
                    "preserve_original": true,
                    "split_on_numerics": true,
                    "stem_english_possessive": true
                }
            }
        }
    },
    "mappings": {
        "city": {
            "_source": {
                "enabled": false
            },
            "dynamic": false,
            "properties": {
                "_all": {
                    "enabled": false
                },
                "autoCompleteName": {
                    "type": "completion",
                    "index_analyzer": "str_index_analyzer",
                    "search_analyzer": "str_search_analyzer"
                }
            }
        }
    }
}

当我搜索“芝加哥”时，它会返回预期结果，因为它找到了与芝加哥匹配的内容，但是，当我搜索“芝加哥”时，它不返回任何内容。我一辈子都无法弄清楚我需要为使搜索不区分大小写而需要更改的内容。如果用户键入“ ChiCAgO”，则应返回我的芝加哥结果，相反，我什么也得不到。

为了测试我的分析仪，我运行了这个：

elasticserver.com/citysuggest/_analyze?text=ChicaGo&pretty

然后我得到了看起来像正确标记化的值。

{
  "tokens": [
    {
      "token": "chicago",
      "start_offset": 0,
      "end_offset": 7,
      "type": "<ALPHANUM>",
      "position": 1
    }
  ]
}