PUT /hotels
{
  "mappings": {
    "properties": {
      "picture": { "type": "keyword" },
      "name": { "type": "text","analyzer": "ik_smart"},
      "score": { "type": "float"},
      "distance": { "type": "float"},
      "desc": { "type": "text" },
      "newPrice": { "type": "float" },
      "oldPrice": { "type": "float" },
      "sale_month": { "type": "integer" },
      "location": { 
        "type": "geo_point" 
      }
    }
  }
}

<dependency>
    <groupId>org.elasticsearch.client</groupId>
    <artifactId>elasticsearch-rest-high-level-client</artifactId>
    <version>7.12.1</version>
</dependency>

// 当前用户的地理坐标
const position = ref(null);

function getUserLocation(){
    if (navigator.geolocation) {
    navigator.geolocation.getCurrentPosition(
      (pos) => {
        position.value = {
          lat: pos.coords.latitude,
          lng: pos.coords.longitude,
        };
        // 根据用户地理坐标获取周围指定距离的酒店
        getNearHotel(position.value);
        // console.log("当前用户地理位置：",position.value);
      },
      (err) => {
        error.value = err.message;
      }
    );
  } else {
    error.value = 'Geolocation is not supported by this browser.';
  }
}

@PostMapping("/searchByLocation")
public List<Map<String, Object>> searchHotelsByLocation(
        @RequestBody SearchVo searchVo
        ) throws IOException {

    // 构建查询请求
    SearchRequest searchRequest = new SearchRequest("hotels");

    // 构建查询DSL
    SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
    BoolQueryBuilder boolQuery = QueryBuilders.boolQuery();
    boolQuery.filter(QueryBuilders.geoDistanceQuery("location")
            .point(searchVo.getLat(), searchVo.getLon())
            .distance(searchVo.getRadiusKm(), DistanceUnit.KILOMETERS));

    sourceBuilder.query(boolQuery);
    sourceBuilder.sort(SortBuilders.geoDistanceSort("location", searchVo.getLat(), searchVo.getLon())
            .order(SortOrder.ASC) // 实现升序排序，距离越近越靠前
            .unit(DistanceUnit.KILOMETERS));

    searchRequest.source(sourceBuilder);

    // 执行查询
    SearchResponse searchResponse = client.search(searchRequest, RequestOptions.DEFAULT);
    SearchHits hits = searchResponse.getHits();
    List<Map<String, Object>> hotels = new ArrayList<>();

    for (SearchHit hit : hits) {
        Map<String, Object> hotel = hit.getSourceAsMap();
        // 可以获取距离信息（如果需要显示距离）
        double distance = (double) hit.getSortValues()[0];
        hotel.put("distance_km", distance);
        hotels.add(hotel);
    }

    return hotels;
}

// 使用圆形过滤，过滤出当前用户指定距离的附近酒店
async function getNearHotel(userLocation){
    // 定义搜索半径
    let radiusKm = 3.0;
    
    // 构造查询参数
    let searchArgs = {
        lat:userLocation.lat,
        lon:userLocation.lng,
        radiusKm:radiusKm
    }

    const res = await axios.post("http://localhost:9009/es/searchByLocation",searchArgs);
    console.log("查询到"+ radiusKm + "公里内，存在"+res.data.length+"家酒店/旅社");
    // 处理距离小数点，保留逗号后两位
    for(let item of res.data){
        item.distance_km = item.distance_km.toFixed(2);
    }
    cardsD.value = res.data
}