Support geo label position as runtime field

docs/changelog/86154.yaml

@@ -0,0 +1,5 @@
+pr: 86154
+summary: Support geo label position as runtime field
+area: Geo
+type: enhancement
+issues: []

modules/lang-painless/src/main/resources/org/elasticsearch/painless/org.elasticsearch.txt

@@ -85,6 +85,7 @@ class org.elasticsearch.index.fielddata.ScriptDocValues$Geometry {
   int getDimensionalType()
   org.elasticsearch.common.geo.GeoPoint getCentroid()
   org.elasticsearch.common.geo.GeoBoundingBox getBoundingBox()
+  org.elasticsearch.common.geo.GeoPoint getLabelPosition()
   double getMercatorWidth()
   double getMercatorHeight()
 }

modules/lang-painless/src/yamlRestTest/resources/rest-api-spec/test/painless/50_script_doc_values.yml

@@ -638,6 +638,18 @@ setup:
     - match: { hits.hits.0.fields.bbox.0.bottom_right.lat: 41.1199999647215 }
     - match: { hits.hits.0.fields.bbox.0.bottom_right.lon: -71.34000004269183 }
 
+    - do:
+        search:
+          rest_total_hits_as_int: true
+          body:
+            query: { term: { _id: "1" } }
+            script_fields:
+              label_position:
+                script:
+                  source: "doc['geo_point'].getLabelPosition()"
+    - match: { hits.hits.0.fields.label_position.0.lat: 41.1199999647215 }
+    - match: { hits.hits.0.fields.label_position.0.lon: -71.34000004269183 }
+
     - do:
         search:
           rest_total_hits_as_int: true
@@ -661,9 +673,9 @@ setup:
           body:
             query: { term: { _id: "1" } }
             script_fields:
-                    type:
-                        script:
-                            source: "doc['geo_point'].getDimensionalType()"
+              type:
+                script:
+                  source: "doc['geo_point'].getDimensionalType()"
     - match: { hits.hits.0.fields.type.0: 0 }
 
     - do:

server/src/internalClusterTest/java/org/elasticsearch/search/geo/GeoPointScriptDocValuesIT.java

@@ -12,6 +12,7 @@
 import org.elasticsearch.action.search.SearchResponse;
 import org.elasticsearch.common.document.DocumentField;
 import org.elasticsearch.common.geo.GeoBoundingBox;
+import org.elasticsearch.common.geo.GeoPoint;
 import org.elasticsearch.geo.GeometryTestUtils;
 import org.elasticsearch.index.fielddata.ScriptDocValues;
 import org.elasticsearch.plugins.Plugin;
@@ -21,6 +22,8 @@
 import org.elasticsearch.test.ESSingleNodeTestCase;
 import org.elasticsearch.xcontent.XContentBuilder;
 import org.elasticsearch.xcontent.XContentFactory;
+import org.hamcrest.BaseMatcher;
+import org.hamcrest.Description;
 import org.hamcrest.Matchers;
 import org.junit.Before;
 
@@ -36,6 +39,8 @@
 import static org.elasticsearch.test.hamcrest.ElasticsearchAssertions.assertSearchResponse;
 import static org.elasticsearch.xcontent.XContentFactory.jsonBuilder;
 import static org.hamcrest.Matchers.equalTo;
+import static org.hamcrest.Matchers.is;
+import static org.hamcrest.Matchers.oneOf;
 
 public class GeoPointScriptDocValuesIT extends ESSingleNodeTestCase {
 
@@ -54,6 +59,8 @@ protected Map<String, Function<Map<String, Object>, Object>> pluginScripts() {
             scripts.put("lon", this::scriptLon);
             scripts.put("height", this::scriptHeight);
             scripts.put("width", this::scriptWidth);
+            scripts.put("label_lat", this::scriptLabelLat);
+            scripts.put("label_lon", this::scriptLabelLon);
             return scripts;
         }
 
@@ -91,15 +98,29 @@ private double scriptLon(Map<String, Object> vars) {
             return geometry.size() == 0 ? Double.NaN : geometry.getCentroid().lon();
         }
 
+        private double scriptLabelLat(Map<String, Object> vars) {
+            Map<?, ?> doc = (Map<?, ?>) vars.get("doc");
+            ScriptDocValues.Geometry<?> geometry = assertGeometry(doc);
+            return geometry.size() == 0 ? Double.NaN : geometry.getLabelPosition().lat();
+        }
+
+        private double scriptLabelLon(Map<String, Object> vars) {
+            Map<?, ?> doc = (Map<?, ?>) vars.get("doc");
+            ScriptDocValues.Geometry<?> geometry = assertGeometry(doc);
+            return geometry.size() == 0 ? Double.NaN : geometry.getLabelPosition().lon();
+        }
+
         private ScriptDocValues.Geometry<?> assertGeometry(Map<?, ?> doc) {
             ScriptDocValues.Geometry<?> geometry = (ScriptDocValues.Geometry<?>) doc.get("location");
             if (geometry.size() == 0) {
                 assertThat(geometry.getBoundingBox(), Matchers.nullValue());
                 assertThat(geometry.getCentroid(), Matchers.nullValue());
+                assertThat(geometry.getLabelPosition(), Matchers.nullValue());
                 assertThat(geometry.getDimensionalType(), equalTo(-1));
             } else {
                 assertThat(geometry.getBoundingBox(), Matchers.notNullValue());
                 assertThat(geometry.getCentroid(), Matchers.notNullValue());
+                assertThat(geometry.getLabelPosition(), Matchers.notNullValue());
                 assertThat(geometry.getDimensionalType(), equalTo(0));
             }
             return geometry;
@@ -140,6 +161,8 @@ public void testRandomPoint() throws Exception {
             .addScriptField("lon", new Script(ScriptType.INLINE, CustomScriptPlugin.NAME, "lon", Collections.emptyMap()))
             .addScriptField("height", new Script(ScriptType.INLINE, CustomScriptPlugin.NAME, "height", Collections.emptyMap()))
             .addScriptField("width", new Script(ScriptType.INLINE, CustomScriptPlugin.NAME, "width", Collections.emptyMap()))
+            .addScriptField("label_lat", new Script(ScriptType.INLINE, CustomScriptPlugin.NAME, "label_lat", Collections.emptyMap()))
+            .addScriptField("label_lon", new Script(ScriptType.INLINE, CustomScriptPlugin.NAME, "label_lon", Collections.emptyMap()))
             .get();
         assertSearchResponse(searchResponse);
 
@@ -151,6 +174,10 @@ public void testRandomPoint() throws Exception {
         assertThat(fields.get("lon").getValue(), equalTo(qLon));
         assertThat(fields.get("height").getValue(), equalTo(0d));
         assertThat(fields.get("width").getValue(), equalTo(0d));
+
+        // Check label position is the same point
+        assertThat(fields.get("label_lon").getValue(), equalTo(qLon));
+        assertThat(fields.get("label_lat").getValue(), equalTo(qLat));
     }
 
     public void testRandomMultiPoint() throws Exception {
@@ -178,6 +205,8 @@ public void testRandomMultiPoint() throws Exception {
             .addScriptField("lon", new Script(ScriptType.INLINE, CustomScriptPlugin.NAME, "lon", Collections.emptyMap()))
             .addScriptField("height", new Script(ScriptType.INLINE, CustomScriptPlugin.NAME, "height", Collections.emptyMap()))
             .addScriptField("width", new Script(ScriptType.INLINE, CustomScriptPlugin.NAME, "width", Collections.emptyMap()))
+            .addScriptField("label_lat", new Script(ScriptType.INLINE, CustomScriptPlugin.NAME, "label_lat", Collections.emptyMap()))
+            .addScriptField("label_lon", new Script(ScriptType.INLINE, CustomScriptPlugin.NAME, "label_lon", Collections.emptyMap()))
             .get();
         assertSearchResponse(searchResponse);
 
@@ -196,6 +225,11 @@ public void testRandomMultiPoint() throws Exception {
         assertThat(fields.get("lon").getValue(), equalTo(centroidLon));
         assertThat(fields.get("height").getValue(), equalTo(height));
         assertThat(fields.get("width").getValue(), equalTo(width));
+
+        // Check label position is one of the incoming points
+        double labelLat = fields.get("label_lat").getValue();
+        double labelLon = fields.get("label_lon").getValue();
+        assertThat("Label should be one of the points", new GeoPoint(labelLat, labelLon), isMultiPointLabelPosition(lats, lons));
     }
 
     public void testNullPoint() throws Exception {
@@ -221,4 +255,29 @@ public void testNullPoint() throws Exception {
         assertThat(fields.get("height").getValue(), equalTo(Double.NaN));
         assertThat(fields.get("width").getValue(), equalTo(Double.NaN));
     }
+
+    private static MultiPointLabelPosition isMultiPointLabelPosition(double[] lats, double[] lons) {
+        return new MultiPointLabelPosition(lats, lons);
+    }
+
+    private static class MultiPointLabelPosition extends BaseMatcher<GeoPoint> {
+        private final GeoPoint[] points;
+
+        private MultiPointLabelPosition(double[] lats, double[] lons) {
+            points = new GeoPoint[lats.length];
+            for (int i = 0; i < lats.length; i++) {
+                points[i] = new GeoPoint(lats[i], lons[i]);
+            }
+        }
+
+        @Override
+        public boolean matches(Object actual) {
+            return is(oneOf(points)).matches(actual);
+        }
+
+        @Override
+        public void describeTo(Description description) {
+            description.appendText("is(oneOf(" + Arrays.toString(points) + ")");
+        }
+    }
 }

server/src/main/java/org/elasticsearch/index/fielddata/ScriptDocValues.java

@@ -232,6 +232,9 @@ public Geometry(Supplier<T> supplier) {
         /** Returns the bounding box of this geometry  */
         public abstract GeoBoundingBox getBoundingBox();
 
+        /** Returns the suggested label position  */
+        public abstract GeoPoint getLabelPosition();
+
         /** Returns the centroid of this geometry  */
         public abstract GeoPoint getCentroid();
 
@@ -247,6 +250,8 @@ public interface GeometrySupplier<T> extends Supplier<T> {
         GeoPoint getInternalCentroid();
 
         GeoBoundingBox getInternalBoundingBox();
+
+        GeoPoint getInternalLabelPosition();
     }
 
     public static class GeoPoints extends Geometry<GeoPoint> {
@@ -363,6 +368,11 @@ public double getMercatorHeight() {
         public GeoBoundingBox getBoundingBox() {
             return size() == 0 ? null : geometrySupplier.getInternalBoundingBox();
         }
+
+        @Override
+        public GeoPoint getLabelPosition() {
+            return size() == 0 ? null : geometrySupplier.getInternalLabelPosition();
+        }
     }
 
     public static class Booleans extends ScriptDocValues<Boolean> {

server/src/main/java/org/elasticsearch/index/mapper/GeoShapeQueryable.java

@@ -44,7 +44,12 @@ public interface GeoShapeQueryable {
     Query geoShapeQuery(SearchExecutionContext context, String fieldName, ShapeRelation relation, LatLonGeometry... luceneGeometries);
 
     default Query geoShapeQuery(SearchExecutionContext context, String fieldName, ShapeRelation relation, Geometry shape) {
-        final LatLonGeometry[] luceneGeometries = toQuantizeLuceneGeometry(fieldName, context, shape, relation);
+        final LatLonGeometry[] luceneGeometries;
+        try {
+            luceneGeometries = toQuantizeLuceneGeometry(shape, relation);
+        } catch (IllegalArgumentException e) {
+            throw new QueryShardException(context, "Exception creating query on Field [" + fieldName + "] " + e.getMessage(), e);
+        }
         if (luceneGeometries.length == 0) {
             return new MatchNoDocsQuery();
         }
@@ -82,12 +87,7 @@ private static double[] quantizeLons(double[] lons) {
      * transforms an Elasticsearch {@link Geometry} into a lucene {@link LatLonGeometry} and quantize
      * the latitude and longitude values to match the values on the index.
      */
-    private static LatLonGeometry[] toQuantizeLuceneGeometry(
-        String name,
-        SearchExecutionContext context,
-        Geometry geometry,
-        ShapeRelation relation
-    ) {
+    static LatLonGeometry[] toQuantizeLuceneGeometry(Geometry geometry, ShapeRelation relation) {
         if (geometry == null) {
             return new LatLonGeometry[0];
         }
@@ -130,7 +130,7 @@ public Void visit(org.elasticsearch.geometry.Line line) {
                     if (relation == ShapeRelation.WITHIN) {
                         // Line geometries and WITHIN relation is not supported by Lucene. Throw an error here
                         // to have same behavior for runtime fields.
-                        throw new QueryShardException(context, "Field [" + name + "] found an unsupported shape Line");
+                        throw new IllegalArgumentException("found an unsupported shape Line");
                     }
                     geometries.add(new org.apache.lucene.geo.Line(quantizeLats(line.getLats()), quantizeLons(line.getLons())));
                 }
@@ -139,7 +139,7 @@ public Void visit(org.elasticsearch.geometry.Line line) {
 
             @Override
             public Void visit(LinearRing ring) {
-                throw new QueryShardException(context, "Field [" + name + "] found an unsupported shape LinearRing");
+                throw new IllegalArgumentException("Found an unsupported shape LinearRing");
             }
 
             @Override

server/src/main/java/org/elasticsearch/script/field/GeoPointDocValuesField.java

@@ -11,6 +11,7 @@
 import org.apache.lucene.util.ArrayUtil;
 import org.elasticsearch.common.geo.GeoBoundingBox;
 import org.elasticsearch.common.geo.GeoPoint;
+import org.elasticsearch.common.geo.GeoUtils;
 import org.elasticsearch.index.fielddata.MultiGeoPointValues;
 import org.elasticsearch.index.fielddata.ScriptDocValues;
 
@@ -34,6 +35,7 @@ public class GeoPointDocValuesField extends AbstractScriptFieldFactory<GeoPoint>
     private ScriptDocValues.GeoPoints geoPoints = null;
     private final GeoPoint centroid = new GeoPoint();
     private final GeoBoundingBox boundingBox = new GeoBoundingBox(new GeoPoint(), new GeoPoint());
+    private int labelIndex = 0;
 
     public GeoPointDocValuesField(MultiGeoPointValues input, String name) {
         this.input = input;
@@ -71,11 +73,13 @@ private void setSingleValue() throws IOException {
         centroid.reset(point.lat(), point.lon());
         boundingBox.topLeft().reset(point.lat(), point.lon());
         boundingBox.bottomRight().reset(point.lat(), point.lon());
+        labelIndex = 0;
     }
 
     private void setMultiValue() throws IOException {
         double centroidLat = 0;
         double centroidLon = 0;
+        labelIndex = 0;
         double maxLon = Double.NEGATIVE_INFINITY;
         double minLon = Double.POSITIVE_INFINITY;
         double maxLat = Double.NEGATIVE_INFINITY;
@@ -89,12 +93,22 @@ private void setMultiValue() throws IOException {
             minLon = Math.min(minLon, values[i].getLon());
             maxLat = Math.max(maxLat, values[i].getLat());
             minLat = Math.min(minLat, values[i].getLat());
+            labelIndex = closestPoint(labelIndex, i, (minLat + maxLat) / 2, (minLon + maxLon) / 2);
         }
         centroid.reset(centroidLat / count, centroidLon / count);
         boundingBox.topLeft().reset(maxLat, minLon);
         boundingBox.bottomRight().reset(minLat, maxLon);
     }
 
+    private int closestPoint(int a, int b, double lat, double lon) {
+        if (a == b) {
+            return a;
+        }
+        double distA = GeoUtils.planeDistance(lat, lon, values[a].lat(), values[a].lon());
+        double distB = GeoUtils.planeDistance(lat, lon, values[b].lat(), values[b].lon());
+        return distA < distB ? a : b;
+    }
+
     @Override
     public ScriptDocValues<GeoPoint> toScriptDocValues() {
         if (geoPoints == null) {
@@ -121,6 +135,11 @@ public GeoBoundingBox getInternalBoundingBox() {
         return boundingBox;
     }
 
+    @Override
+    public GeoPoint getInternalLabelPosition() {
+        return values[labelIndex];
+    }
+
     @Override
     public String getName() {
         return name;