ES地理范围查询第二讲：地理位置信息之geo_shape

1.前言

在前面我简单的介绍了es对地理位置点的相关操作，包括获取多边形内（凸多边形）的点及计算两点之间的距离，或者按照距离的远近排序的简要查询方法，但是假如我们的想要查询落在一个凹多边形内的点，使用geo_point类型的就满足不了我们的需求了，这时候es引入了geo_shape类型。

2. Geo_shape

geo_shape支持GeoJson和WKT(Well-Known Text,==6.X以后的版本支持==)格式的形状,
一个典型的GeoJson表示的点：

{
    "type": "Point",
    "coordinates": [125.6, 10.1]
  }

一个典型的用WKT表示的点：

POINT(125.6 10.1)

详细介绍，基于支持的这些形状，我们可以实现更加复杂的查询，包括多边形（矩形、圆形、多边形等）内的点，多边形的相交，直线等等；

3. 业务场景

获取一个城市地理范围（不规则）内的坐标点。一个典型的不规则的城市地理位置的坐标形式如下（WKT）:

MULTIPOLYGON(((110.390839 24.038563,110.392876 24.035597,110.393425 24.030552,110.393707 24.027109,110.393997 24.023668,110.393539 24.01976,110.391083 24.014458,110.38887 24.01053,110.386658 24.00638,110.384613 23.999998,110.386757 23.991854,110.388741 23.986572,110.389236 23.985193,110.39122 23.981291,110.392174 23.972574,110.391907 23.967531,110.389359 23.958139,110.38356 23.948992,110.375526 23.942373,110.36451 23.938519,110.358002 23.936707,110.354736 23.934425,110.349701 23.924356,110.347908 23.915421,110.348373 23.907164,110.348839 23.900513,110.352562 23.89385,110.360031 23.888321,110.367767 23.885538,110.374512 23.884136,110.378258 23.883665,110.386497 23.882486,110.394241 23.881083,110.398972 23.877165,110.402451 23.873713,110.403931 23.869577,110.406914 23.865669,110.412651 23.8645,110.418404 23.865852,110.421913 23.866066,110.425659 23.866968,110.429161 23.868328,110.43541 23.868761,110.439148 23.866684,110.441383 23.864155,110.446114 23.858171,110.449089 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23.330566,109.214363 23.336994,109.223297 23.341841,109.235992 23.344402,109.245941 23.348791,109.255379 23.357536,109.259087 23.363514,109.278473 23.379168,109.288399 23.389977,109.304039 23.405619,109.314217 23.415741,109.328407 23.421282,109.344856 23.419485,109.34935 23.417433,109.352852 23.410328,109.358093 23.40575,109.366333 23.403475,109.372063 23.39913,109.373573 23.391562,109.375343 23.386061,109.384552 23.384014,109.398743 23.388174,109.405724 23.384975,109.40947 23.379705,109.412483 23.372601,109.419952 23.368715,109.430908 23.371717,109.434883 23.375626,109.446327 23.383677,109.452301 23.386209,109.46376 23.385309,109.47123 23.384176,109.477966 23.378681,109.484207 23.372036,109.487709 23.363325,109.493057 23.354374,109.496986 23.346977,109.504791 23.336708,109.511848 23.331282,109.522774 23.323627,109.534027 23.317266,109.540573 23.312922,109.549026 23.311323,109.560226 23.311796,109.562973 23.314095,109.563217 23.318682,109.563332 23.325277,109.561447 23.331299,109.562447 23.33497,109.57003 23.354408,109.580048 23.367092,109.591911 23.370747,109.599564 23.375654,109.604065 23.379894,109.612213 23.387321,109.62191 23.399031,109.629868 23.411425,109.635597 23.421982,109.646057 23.42864,109.660751 23.429794,109.669983 23.425211,109.679192 23.416725,109.685173 23.410074,109.689163 23.406176,109.695892 23.404114,109.701622 23.40572,109.704613 23.407784,109.706596 23.408703,109.71183 23.415356,109.716812 23.420864,109.719803 23.426371,109.723541 23.438988,109.722542 23.447016,109.720299 23.451605,109.719299 23.459173,109.721298 23.462847,109.727524 23.465828,109.734253 23.465828,109.740982 23.463991,109.74572 23.464453,109.750687 23.4645,109.757919 23.46476,109.765633 23.467543,109.769363 23.469851,109.773323 23.475369,109.77626 23.486835,109.777992 23.489594,109.781471 23.49144,109.789703 23.491932,109.816628 23.487919,109.827103 23.487961,109.836823 23.485706,109.842346 23.474501,109.842819 23.473051,109.846413 23.471069,109.8479 23.469231,109.852379 23.463493,109.857361 23.460966,109.864853 23.465092,109.869827 23.470821,109.875572 23.479305,109.881561 23.484346,109.888313 23.493746,109.893051 23.506586,109.894318 23.521727,109.892593 23.531364,109.889847 23.539625,109.889122 23.556828,109.89138 23.567839,109.897881 23.580681,109.906372 23.588015,109.913368 23.59741,109.918129 23.611628,109.920639 23.623093,109.923401 23.637999,109.921432 23.655436,109.918701 23.667826,109.919724 23.680899,109.921471 23.684567,109.924217 23.687775,109.92672 23.68869,109.935707 23.68891,109.943199 23.690966,109.947708 23.701967,109.946983 23.712294,109.94899 23.725592,109.950737 23.728804,109.960487 23.734293,109.967491 23.73933,109.974747 23.74987,109.979523 23.762249,109.983032 23.771418,109.99279 23.779428,110.000793 23.781025,110.003029 23.780563,110.023521 23.78351,110.03727 23.788759,110.048523 23.795162,110.05703 23.799961,110.063782 23.803848,110.069542 23.810259,110.078568 23.822857,110.084839 23.831329,110.090103 23.835903,110.103867 23.847572,110.115646 23.858784,110.127693 23.872517,110.137451 23.880289,110.145714 23.88348,110.153214 23.881859,110.161926 23.875874,110.169411 23.868284,110.175888 23.863453,110.185638 23.863655,110.19516 23.872114,110.199203 23.884029,110.200737 23.893658,110.201767 23.905579,110.206299 23.912907,110.214798 23.911278,110.221024 23.90461,110.2295 23.898849,110.236732 23.894241,110.250504 23.897181,110.257736 23.895323,110.261711 23.888889,110.270638 23.869823,110.275101 23.860407,110.282578 23.856712,110.292839 23.860807,110.296127 23.86974,110.295158 23.877771,110.298698 23.886932,110.302711 23.891048,110.311989 23.898125,110.316559 23.913935,110.315323 23.917837,110.3004 23.936008,110.294434 23.944284,110.290459 23.951406,110.291496 23.962641,110.296799 23.972713,110.301353 23.983936,110.303879 23.991264,110.304649 23.99585,110.30587 23.999998,110.299744 24.007362,110.300446 24.011963,110.301399 24.016104,110.304848 24.021191,110.309814 24.025602,110.317276 24.029812,110.323517 24.031939,110.330986 24.036606,110.337975 24.038971,110.343979 24.039488,110.350494 24.039553,110.355263 24.03845,110.361748 24.041039,110.368973 24.045471,110.373955 24.047586,110.376923 24.051517,110.379707 24.049017,110.383499 24.045382,110.388298 24.041983,110.390839 24.038563)))

注意的问题

1. index的mapping必须显式声明该字段为geo_shape类型

{
    "ex_index_city_city": {
        "mappings": {
            "ex_type_city_city": {
                "_all": {
                    "enabled": true,
                    "analyzer": "ik_max_word"
                },
                "properties": {
                    "geo_position": {
                        "type": "geo_shape"
                    },
                    "labelId": {
                        "type": "keyword"
                    },
                    "location": {
                        "type": "keyword"
                    },
                    "name": {
                        "type": "keyword"
                    }
                }
            }
        }
    }
}

2. elasticsearch在高于6.x的版本才对WKT格式的经纬度进行了直接的支持，因此假如你的版本==低于6.x==，在导入数据时需要将WKT格式的转换为GeoJSON.

4.WKT转GeoJson

实体类GeoShapeEntity

public class GeoShapeEntity implements Serializable{

    private static final long serialVersionUID = -4507270609977265606L;
    private String type;
    private Object coordinates;

    public String getType() {
        return type;
    }

    public void setType(String type) {
        this.type = type;
    }

    public Object getCoordinates() {
        return coordinates;
    }

    public void setCoordinates(Object coordinates) {
        this.coordinates = coordinates;
    }
}

转换类WKTReaderUtils

private final static Logger logger = LoggerFactory.getLogger(WKTReaderUtils.class);

    private final static WKTReader wktReader = new WKTReader();

    /**
     * 纬度范围
     */
    private final static String[] LAT_BOUNDARY = new String[]{"-90.0","90.0"};
    /**
     * 经度范围
     */
    private final static String[] LON_BOUNDARY = new String[]{"-180.0","180.0"};

    /**
     * 将WKT文本字符串转换为ES中的GeoShape字符串格式
     *
     * @param wkt
     * @return
     */
    public static GeoShapeEntity getESGeoTextFromWkt(String wkt) {
        GeoShapeEntity entity = new GeoShapeEntity();
        try {
            Geometry geom = wktReader.read(wkt);
            if (Objects.isNull(geom)){
                logger.warn("convert wkt to Geometry error!wkt:{}",wkt);
                return null;
            }
            String type = geom.getClass().getSimpleName().toLowerCase();
            Point point;
            MultiPoint multiPoint;
            LineString lineString;
            MultiLineString multiLineString;
            Polygon polygon;
            MultiPolygon multiPolygon;
            Object result = null;
            if (type.equals(GeoShapeEnum.POINT.getEnumFeild())) {
                point = (Point) geom;
                result = getESPointText(point);
            } else if (type.equals(GeoShapeEnum.LINESTRING.getEnumFeild())) {
                lineString = (LineString) geom;
                result = getESLineStringText(lineString);
            } else if (type.equals(GeoShapeEnum.POLYGON.getEnumFeild())) {
                polygon = (Polygon) geom;
                result = getESPolygonText(polygon);
            } else if (type.equals(GeoShapeEnum.MULTIPOINT.getEnumFeild())) {
                multiPoint = (MultiPoint) geom;
                result = getESMultiPointText(multiPoint);
            } else if (type.equals(GeoShapeEnum.MULTILINESTRING.getEnumFeild())) {
                multiLineString = (MultiLineString) geom;
                result = getESMultiLineStringText(multiLineString);
            } else if (type.equals(GeoShapeEnum.MULTIPOLYGON.getEnumFeild())) {
                multiPolygon = (MultiPolygon) geom;
                result = getESMultiPolygonText(multiPolygon);
            }
            entity.setType(type);
            entity.setCoordinates(result);
        } catch (ParseException e) {
            Double[] result = getESPointText(wkt);
            entity.setType("point");
            entity.setCoordinates(result);
        }
        return entity;
    }

    /**
     * 通过MultiPolygon对象拼接中括号表示的字符串
     *
     * @param multiPolygon
     * @return
     */
    private static List