Nested字段在单独的上下文中操作，并且它们的内容不能从外部级别访问，反之亦然。

但是，您可以访问文档的raw _source。

但有一个问题：

• 请参阅，当在offices嵌套路径下迭代时，您可以调用.arcDistance，因为coordinates的类型为ScriptDocValues.GeoPoint。
• 但是，一旦访问原始的_source，您将处理一组未优化的java.util.ArrayList和java.util.HashMap。

这意味着即使您可以迭代数组列表：

...
for (def office : params._source['offices']) {
   // office.coordinates is a trivial HashMap of {lat, lon}!
}

计算地理距离是不可能的
...除非您编写自己的geoDistance函数--这对于Painless来说完全可以，但是需要在脚本的顶部定义它。

• 无需重新发明轮子：Calculating distance between two points, using latitude longitude?*

示例实现

假设您的文档如下所示：

POST my-index/_doc
{
  "offices": [
    {
      "coordinates": "39.9,-74.92",
      "state": "New Jersey"
    }
  ],
  "headquarters": {
    "coordinates": {
      "lat": 40.7128,
      "lon": -74.006
    },
    "state": "NYC"
  }
}

您的排序脚本可能如下所示：

GET my-index/_search
{
   "sort": [
    {
      "_script": {
        "order": "asc",
        "script": {
          "lang": "painless",
          "params": {
            "lat": 28.9672,
            "lon": -98.4786
          },
          "source": """
            // We can declare functions at the beginning of a Painless script
            // https://www.elastic.co/guide/en/elasticsearch/painless/current/painless-functions.html#painless-functions

            double deg2rad(double deg) {
              return (deg * Math.PI / 180.0);
            }

            double rad2deg(double rad) {
              return (rad * 180.0 / Math.PI);
            }

            // https://stackoverflow.com/a/3694410/8160318
            double geoDistanceInMiles(def lat1, def lon1, def lat2, def lon2) {
              double theta = lon1 - lon2;
              double dist = Math.sin(deg2rad(lat1)) * Math.sin(deg2rad(lat2)) + Math.cos(deg2rad(lat1)) * Math.cos(deg2rad(lat2)) * Math.cos(deg2rad(theta));
              dist = Math.acos(dist);
              dist = rad2deg(dist);
              return dist * 60 * 1.1515;
            }

            // start off arbitrarily high            
            def hqDistance = 1000000;

            if (!doc['headquarters.coordinates'].empty) {
              hqDistance = doc['headquarters.coordinates'].arcDistance(params.lat, params.lon) * 0.000621371;
            }

            // assume office distance as large as hq distance
            def officeDistance = hqDistance;

            // iterate each office and compare it to the currently lowest officeDistance
            for (def office : params._source['offices']) {
              // the coordinates are formatted as "lat,lon" so let's split...
              def latLong = Arrays.asList(office.coordinates.splitOnToken(","));
              // ...and parse them before passing onwards
              def tmpOfficeDistance = geoDistanceInMiles(Float.parseFloat(latLong[0]),
                                                         Float.parseFloat(latLong[1]),
                                                         params.lat,
                                                         params.lon);
              // we're interested in the nearest office...
              if (tmpOfficeDistance < officeDistance) {
                officeDistance = tmpOfficeDistance;
              }
            }

            if (hqDistance < officeDistance) {
              return hqDistance;
            }

            return officeDistance;
          """
        },
        "type": "Number"
      }
    }
  ]
}

无耻的塞：我深入研究了dedicated chapter of my ES Handbook中的Elasticsearch脚本。