Elasticsearch 6 创建索引报错：

Invalid index name [testDemo], must be lowercase

原因：Elasticsearch 6 默认索引类型是_doc，如果想改变则要指定索引类型

示例：

PUT testDemo
{
  "mappings": {
    "properties": {
      "name": {
        "type": "text"
      },
      "location": {
        "type": "geo_point"
      }
    }
   }
}

返回：

{
  "error": {
    "root_cause": [
      {
        "type": "invalid_index_name_exception",
        "reason": "Invalid index name [testDemo], must be lowercase",
        "index_uuid": "_na_",
        "index": "testDemo"
      }
    ],
    "type": "invalid_index_name_exception",
    "reason": "Invalid index name [testDemo], must be lowercase",
    "index_uuid": "_na_",
    "index": "testDemo"
  },
  "status": 400
}

指定索引类型：

PUT testDemo
{
  "mappings": {
    "product": {
    "properties": {
      "name": {
        "type": "text"
      },
      "location": {
        "type": "geo_point"
      }
    }
   }
  }
}

结果：

{
  "acknowledged" : true,
  "shards_acknowledged" : true,
  "index" : "testDemo"
}

product为指定索引类型