[Geo] Add Well Known Text (WKT) Parsing Support to ShapeBuilders

This commit adds WKT support to Geo ShapeBuilders.

This supports the following format:

POINT (30 10)
LINESTRING (30 10, 10 30, 40 40)
BBOX (-10, 10, 10, -10)
POLYGON ((30 10, 40 40, 20 40, 10 20, 30 10))
POLYGON ((35 10, 45 45, 15 40, 10 20, 35 10), (20 30, 35 35, 30 20, 20 30))
MULTIPOINT ((10 40), (40 30), (20 20), (30 10))
MULTIPOINT (10 40, 40 30, 20 20, 30 10)
MULTILINESTRING ((10 10, 20 20, 10 40),(40 40, 30 30, 40 20, 30 10))
MULTIPOLYGON (((30 20, 45 40, 10 40, 30 20)), ((15 5, 40 10, 10 20, 5 10, 15 5)))
MULTIPOLYGON (((40 40, 20 45, 45 30, 40 40)), ((20 35, 10 30, 10 10, 30 5, 45 20, 20 35), (30 20, 20 15, 20 25, 30 20)))
GEOMETRYCOLLECTION (POINT (30 10), MULTIPOINT ((10 40), (40 30), (20 20), (30 10)))

closes #9120

core/src/main/java/org/elasticsearch/common/geo/GeoShapeType.java

@@ -241,6 +241,11 @@ CoordinateNode validate(CoordinateNode coordinates, boolean coerce) {
             }
             return coordinates;
         }
+
+        @Override
+        public String wktName() {
+            return BBOX;
+        }
     },
     CIRCLE("circle") {
         @Override
@@ -273,11 +278,13 @@ CoordinateNode validate(CoordinateNode coordinates, boolean coerce) {
 
     private final String shapename;
     private static Map<String, GeoShapeType> shapeTypeMap = new HashMap<>();
+    private static final String BBOX = "BBOX";
 
     static {
         for (GeoShapeType type : values()) {
             shapeTypeMap.put(type.shapename, type);
         }
+        shapeTypeMap.put(ENVELOPE.wktName().toLowerCase(Locale.ROOT), ENVELOPE);
     }
 
     GeoShapeType(String shapename) {
@@ -300,6 +307,11 @@ public abstract ShapeBuilder getBuilder(CoordinateNode coordinates, DistanceUnit
                                             ShapeBuilder.Orientation orientation, boolean coerce);
     abstract CoordinateNode validate(CoordinateNode coordinates, boolean coerce);
 
+    /** wkt shape name */
+    public String wktName() {
+        return this.shapename;
+    }
+
     public static List<Entry> getShapeWriteables() {
         List<Entry> namedWriteables = new ArrayList<>();
         namedWriteables.add(new Entry(ShapeBuilder.class, PointBuilder.TYPE.shapeName(), PointBuilder::new));
@@ -313,4 +325,9 @@ public static List<Entry> getShapeWriteables() {
         namedWriteables.add(new Entry(ShapeBuilder.class, GeometryCollectionBuilder.TYPE.shapeName(), GeometryCollectionBuilder::new));
         return namedWriteables;
     }
+
+    @Override
+    public String toString() {
+        return this.shapename;
+    }
 }

core/src/main/java/org/elasticsearch/common/geo/builders/CircleBuilder.java

@@ -168,6 +168,11 @@ public GeoShapeType type() {
         return TYPE;
     }
 
+    @Override
+    public String toWKT() {
+        throw new UnsupportedOperationException("The WKT spec does not support CIRCLE geometry");
+    }
+
     @Override
     public int hashCode() {
         return Objects.hash(center, radius, unit.ordinal());

core/src/main/java/org/elasticsearch/common/geo/builders/EnvelopeBuilder.java

@@ -20,6 +20,7 @@
 package org.elasticsearch.common.geo.builders;
 
 import org.elasticsearch.common.geo.GeoShapeType;
+import org.elasticsearch.common.geo.parsers.GeoWKTParser;
 import org.elasticsearch.common.geo.parsers.ShapeParser;
 import org.locationtech.spatial4j.shape.Rectangle;
 import com.vividsolutions.jts.geom.Coordinate;
@@ -70,6 +71,28 @@ public Coordinate bottomRight() {
         return this.bottomRight;
     }
 
+    @Override
+    protected StringBuilder contentToWKT() {
+        StringBuilder sb = new StringBuilder();
+
+        sb.append(GeoWKTParser.LPAREN);
+        // minX, maxX, maxY, minY
+        sb.append(topLeft.x);
+        sb.append(GeoWKTParser.COMMA);
+        sb.append(GeoWKTParser.SPACE);
+        sb.append(bottomRight.x);
+        sb.append(GeoWKTParser.COMMA);
+        sb.append(GeoWKTParser.SPACE);
+        // TODO support Z??
+        sb.append(topLeft.y);
+        sb.append(GeoWKTParser.COMMA);
+        sb.append(GeoWKTParser.SPACE);
+        sb.append(bottomRight.y);
+        sb.append(GeoWKTParser.RPAREN);
+
+        return sb;
+    }
+
     @Override
     public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
         builder.startObject();

core/src/main/java/org/elasticsearch/common/geo/builders/GeometryCollectionBuilder.java

@@ -21,6 +21,7 @@
 
 import org.elasticsearch.common.geo.GeoShapeType;
 import org.elasticsearch.common.geo.parsers.ShapeParser;
+import org.elasticsearch.common.geo.parsers.GeoWKTParser;
 import org.locationtech.spatial4j.shape.Shape;
 
 import org.elasticsearch.ElasticsearchException;
@@ -136,6 +137,23 @@ public XContentBuilder toXContent(XContentBuilder builder, Params params) throws
         return builder.endObject();
     }
 
+    @Override
+    protected StringBuilder contentToWKT() {
+        StringBuilder sb = new StringBuilder();
+        if (shapes.isEmpty()) {
+            sb.append(GeoWKTParser.EMPTY);
+        } else {
+            sb.append(GeoWKTParser.LPAREN);
+            sb.append(shapes.get(0).toWKT());
+            for (int i = 1; i < shapes.size(); ++i) {
+                sb.append(GeoWKTParser.COMMA);
+                sb.append(shapes.get(i).toWKT());
+            }
+            sb.append(GeoWKTParser.RPAREN);
+        }
+        return sb;
+    }
+
     @Override
     public GeoShapeType type() {
         return TYPE;

core/src/main/java/org/elasticsearch/common/geo/builders/MultiLineStringBuilder.java

@@ -20,8 +20,8 @@
 package org.elasticsearch.common.geo.builders;
 
 import org.elasticsearch.common.geo.GeoShapeType;
+import org.elasticsearch.common.geo.parsers.GeoWKTParser;
 import org.elasticsearch.common.geo.parsers.ShapeParser;
-import org.locationtech.spatial4j.shape.Shape;
 import com.vividsolutions.jts.geom.Coordinate;
 import com.vividsolutions.jts.geom.Geometry;
 import com.vividsolutions.jts.geom.LineString;
@@ -82,6 +82,25 @@ public GeoShapeType type() {
         return TYPE;
     }
 
+    @Override
+    protected StringBuilder contentToWKT() {
+        final StringBuilder sb = new StringBuilder();
+        if (lines.isEmpty()) {
+            sb.append(GeoWKTParser.EMPTY);
+        } else {
+            sb.append(GeoWKTParser.LPAREN);
+            if (lines.size() > 0) {
+                sb.append(ShapeBuilder.coordinateListToWKT(lines.get(0).coordinates));
+            }
+            for (int i = 1; i < lines.size(); ++i) {
+                sb.append(GeoWKTParser.COMMA);
+                sb.append(ShapeBuilder.coordinateListToWKT(lines.get(i).coordinates));
+            }
+            sb.append(GeoWKTParser.RPAREN);
+        }
+        return sb;
+    }
+
     @Override
     public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
         builder.startObject();

core/src/main/java/org/elasticsearch/common/geo/builders/MultiPolygonBuilder.java

@@ -21,6 +21,7 @@
 
 import org.elasticsearch.common.geo.GeoShapeType;
 import org.elasticsearch.common.geo.parsers.ShapeParser;
+import org.elasticsearch.common.geo.parsers.GeoWKTParser;
 import org.locationtech.spatial4j.shape.Shape;
 import com.vividsolutions.jts.geom.Coordinate;
 
@@ -101,6 +102,37 @@ public List<PolygonBuilder> polygons() {
         return polygons;
     }
 
+    private static String polygonCoordinatesToWKT(PolygonBuilder polygon) {
+        StringBuilder sb = new StringBuilder();
+        sb.append(GeoWKTParser.LPAREN);
+        sb.append(ShapeBuilder.coordinateListToWKT(polygon.shell().coordinates));
+        for (LineStringBuilder hole : polygon.holes()) {
+            sb.append(GeoWKTParser.COMMA);
+            sb.append(ShapeBuilder.coordinateListToWKT(hole.coordinates));
+        }
+        sb.append(GeoWKTParser.RPAREN);
+        return sb.toString();
+    }
+
+    @Override
+    protected StringBuilder contentToWKT() {
+        final StringBuilder sb = new StringBuilder();
+        if (polygons.isEmpty()) {
+            sb.append(GeoWKTParser.EMPTY);
+        } else {
+            sb.append(GeoWKTParser.LPAREN);
+            if (polygons.size() > 0) {
+                sb.append(polygonCoordinatesToWKT(polygons.get(0)));
+            }
+            for (int i = 1; i < polygons.size(); ++i) {
+                sb.append(GeoWKTParser.COMMA);
+                sb.append(polygonCoordinatesToWKT(polygons.get(i)));
+            }
+            sb.append(GeoWKTParser.RPAREN);
+        }
+        return sb;
+    }
+
     @Override
     public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
         builder.startObject();

core/src/main/java/org/elasticsearch/common/geo/builders/PolygonBuilder.java

@@ -729,6 +729,19 @@ private static void translate(Coordinate[] points) {
         }
     }
 
+    @Override
+    protected StringBuilder contentToWKT() {
+        StringBuilder sb = new StringBuilder();
+        sb.append('(');
+        sb.append(ShapeBuilder.coordinateListToWKT(shell.coordinates));
+        for (LineStringBuilder hole : holes) {
+            sb.append(", ");
+            sb.append(ShapeBuilder.coordinateListToWKT(hole.coordinates));
+        }
+        sb.append(')');
+        return sb;
+    }
+
     @Override
     public int hashCode() {
         return Objects.hash(shell, holes, orientation);

core/src/main/java/org/elasticsearch/common/geo/builders/ShapeBuilder.java

@@ -27,6 +27,7 @@
 import org.elasticsearch.Assertions;
 import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.geo.GeoShapeType;
+import org.elasticsearch.common.geo.parsers.GeoWKTParser;
 import org.elasticsearch.common.io.stream.NamedWriteable;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
@@ -339,6 +340,47 @@ public String toString() {
         }
     }
 
+    protected StringBuilder contentToWKT() {
+        return coordinateListToWKT(this.coordinates);
+    }
+
+    public String toWKT() {
+        StringBuilder sb = new StringBuilder();
+        sb.append(type().wktName());
+        sb.append(GeoWKTParser.SPACE);
+        sb.append(contentToWKT());
+        return sb.toString();
+    }
+
+    protected static StringBuilder coordinateListToWKT(final List<Coordinate> coordinates) {
+        final StringBuilder sb = new StringBuilder();
+
+        if (coordinates.isEmpty()) {
+            sb.append(GeoWKTParser.EMPTY);
+        } else {
+            // walk through coordinates:
+            sb.append(GeoWKTParser.LPAREN);
+            sb.append(coordinateToWKT(coordinates.get(0)));
+            for (int i = 1; i < coordinates.size(); ++i) {
+                sb.append(GeoWKTParser.COMMA);
+                sb.append(GeoWKTParser.SPACE);
+                sb.append(coordinateToWKT(coordinates.get(i)));
+            }
+            sb.append(GeoWKTParser.RPAREN);
+        }
+
+        return sb;
+    }
+
+    private static String coordinateToWKT(final Coordinate coordinate) {
+        final StringBuilder sb = new StringBuilder();
+        sb.append(coordinate.x + GeoWKTParser.SPACE + coordinate.y);
+        if (Double.isNaN(coordinate.z) == false) {
+            sb.append(GeoWKTParser.SPACE + coordinate.z);
+        }
+        return sb.toString();
+    }
+
     protected static final IntersectionOrder INTERSECTION_ORDER = new IntersectionOrder();
 
     private static final class IntersectionOrder implements Comparator<Edge> {