Add mapper for geoJsonFormat.

src/main/java/org/neo4j/gis/spatial/functions/SpatialFunctions.java

@@ -0,0 +1,43 @@
+/*
+ * Copyright (c) "Neo4j"
+ * Neo4j Sweden AB [http://neo4j.com]
+ *
+ * This file is part of Neo4j Spatial.
+ *
+ * Neo4j is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package org.neo4j.gis.spatial.functions;
+
+import org.locationtech.jts.geom.Geometry;
+import org.locationtech.jts.io.ParseException;
+import org.locationtech.jts.io.WKTReader;
+import org.neo4j.gis.spatial.utilities.GeoJsonUtils;
+import org.neo4j.procedure.Description;
+import org.neo4j.procedure.Name;
+import org.neo4j.procedure.UserFunction;
+
+public class SpatialFunctions {
+
+	@UserFunction("spatial.convert.wktToGeoJson")
+	@Description("Converts a WKT to GeoJson structure")
+	public Object wktToGeoJson(@Name("wkt") String wkt) throws ParseException {
+		if (wkt == null) {
+			return null;
+		}
+		WKTReader wktReader = new WKTReader();
+		Geometry geometry = wktReader.read(wkt);
+		return GeoJsonUtils.toGeoJsonStructure(geometry);
+	}
+}

src/main/java/org/neo4j/gis/spatial/utilities/GeoJsonUtils.java

@@ -0,0 +1,82 @@
+/*
+ * Copyright (c) "Neo4j"
+ * Neo4j Sweden AB [http://neo4j.com]
+ *
+ * This file is part of Neo4j Spatial.
+ *
+ * Neo4j is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package org.neo4j.gis.spatial.utilities;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.Map;
+import java.util.stream.IntStream;
+import java.util.stream.Stream;
+import org.locationtech.jts.geom.Coordinate;
+import org.locationtech.jts.geom.Geometry;
+import org.locationtech.jts.geom.GeometryCollection;
+import org.locationtech.jts.geom.LineString;
+import org.locationtech.jts.geom.Point;
+import org.locationtech.jts.geom.Polygon;
+
+
+public class GeoJsonUtils {
+
+	private GeoJsonUtils() {
+	}
+
+	public static Map<String, Object> toGeoJsonStructure(Geometry geometry) {
+		return Map.of(
+				"type", geometry.getGeometryType(),
+				"coordinates", getCoordinates(geometry)
+		);
+	}
+
+	private static List<?> getCoordinates(Geometry geometry) {
+		if (geometry instanceof Point point) {
+			return getPoint(point.getCoordinate());
+		}
+		if (geometry instanceof LineString lineString) {
+			return Arrays.stream(lineString.getCoordinates()).map(GeoJsonUtils::getPoint).toList();
+		}
+		if (geometry instanceof Polygon polygon) {
+			return Stream.concat(
+							Stream.of(polygon.getExteriorRing()),
+							IntStream.range(0, polygon.getNumInteriorRing())
+									.mapToObj(polygon::getInteriorRingN)
+					)
+					.map(GeoJsonUtils::getCoordinates)
+					.toList();
+		}
+		if (geometry instanceof GeometryCollection geometryCollection) {
+			return IntStream.range(0, geometryCollection.getNumGeometries())
+					.mapToObj(geometryCollection::getGeometryN)
+					.map(GeoJsonUtils::getCoordinates)
+					.toList();
+		}
+		throw new IllegalArgumentException("Unsupported geometry type: " + geometry.getGeometryType());
+	}
+
+	private static List<Object> getPoint(Coordinate coordinate) {
+		if (Double.isNaN(coordinate.getZ())) {
+			return List.of(coordinate.getX(), coordinate.getY());
+		}
+		return List.of(
+				coordinate.getX(),
+				coordinate.getY(),
+				coordinate.getZ());
+	}
+}

src/test/java/org/neo4j/gis/spatial/AbstractApiTest.java

@@ -0,0 +1,120 @@
+/*
+ * Copyright (c) "Neo4j"
+ * Neo4j Sweden AB [http://neo4j.com]
+ *
+ * This file is part of Neo4j Spatial.
+ *
+ * Neo4j is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package org.neo4j.gis.spatial;
+
+import static org.neo4j.configuration.GraphDatabaseSettings.DEFAULT_DATABASE_NAME;
+
+import java.io.File;
+import java.io.IOException;
+import java.nio.file.Path;
+import java.util.Collections;
+import java.util.List;
+import java.util.Map;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.neo4j.configuration.GraphDatabaseSettings;
+import org.neo4j.dbms.api.DatabaseManagementService;
+import org.neo4j.exceptions.KernelException;
+import org.neo4j.graphdb.GraphDatabaseService;
+import org.neo4j.graphdb.Node;
+import org.neo4j.graphdb.ResourceIterator;
+import org.neo4j.graphdb.Transaction;
+import org.neo4j.internal.helpers.collection.Iterators;
+import org.neo4j.io.fs.FileUtils;
+import org.neo4j.kernel.api.procedure.GlobalProcedures;
+import org.neo4j.kernel.internal.GraphDatabaseAPI;
+import org.neo4j.test.TestDatabaseManagementServiceBuilder;
+
+public abstract class AbstractApiTest {
+
+	private DatabaseManagementService databases;
+	protected GraphDatabaseService db;
+
+	@BeforeEach
+	public void setUp() throws KernelException, IOException {
+		Path dbRoot = new File("target/procedures").toPath();
+		FileUtils.deleteDirectory(dbRoot);
+		databases = new TestDatabaseManagementServiceBuilder(dbRoot)
+				.setConfig(GraphDatabaseSettings.procedure_unrestricted, List.of("spatial.*"))
+				.impermanent()
+				.build();
+		db = databases.database(DEFAULT_DATABASE_NAME);
+		registerApiProceduresAndFunctions();
+	}
+
+	protected abstract void registerApiProceduresAndFunctions() throws KernelException;
+
+	protected void registerProceduresAndFunctions(Class<?> api) throws KernelException {
+		GlobalProcedures procedures = ((GraphDatabaseAPI) db).getDependencyResolver()
+				.resolveDependency(GlobalProcedures.class);
+		procedures.registerProcedure(api);
+		procedures.registerFunction(api);
+	}
+
+	@AfterEach
+	public void tearDown() {
+		databases.shutdown();
+	}
+
+	protected long execute(String statement) {
+		return execute(statement, null);
+	}
+
+	protected long execute(String statement, Map<String, Object> params) {
+		try (Transaction tx = db.beginTx()) {
+			if (params == null) {
+				params = Collections.emptyMap();
+			}
+			long count = Iterators.count(tx.execute(statement, params));
+			tx.commit();
+			return count;
+		}
+	}
+
+	protected void executeWrite(String call) {
+		try (Transaction tx = db.beginTx()) {
+			tx.execute(call).accept(v -> true);
+			tx.commit();
+		}
+	}
+
+	protected Node createNode(String call, String column) {
+		return (Node) executeObject(call, null, column);
+	}
+
+	protected Object executeObject(String call, String column) {
+		return executeObject(call, null, column);
+	}
+
+	protected Object executeObject(String call, Map<String, Object> params, String column) {
+		Object obj;
+		try (Transaction tx = db.beginTx()) {
+			if (params == null) {
+				params = Collections.emptyMap();
+			}
+			ResourceIterator<Object> values = tx.execute(call, params).columnAs(column);
+			obj = values.next();
+			values.close();
+			tx.commit();
+		}
+		return obj;
+	}
+}

src/test/java/org/neo4j/gis/spatial/functions/SpatialFunctionsTest.java

@@ -0,0 +1,58 @@
+/*
+ * Copyright (c) "Neo4j"
+ * Neo4j Sweden AB [http://neo4j.com]
+ *
+ * This file is part of Neo4j Spatial.
+ *
+ * Neo4j is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package org.neo4j.gis.spatial.functions;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.equalTo;
+
+import java.util.List;
+import java.util.Map;
+import org.junit.jupiter.api.Test;
+import org.neo4j.exceptions.KernelException;
+import org.neo4j.gis.spatial.AbstractApiTest;
+
+public class SpatialFunctionsTest extends AbstractApiTest {
+
+	@Override
+	protected void registerApiProceduresAndFunctions() throws KernelException {
+		registerProceduresAndFunctions(SpatialFunctions.class);
+	}
+
+	@Test
+	public void wktToGeoJson() {
+		String wkt = "MULTIPOLYGON(((15.3 60.2, 15.3 60.4, 15.7 60.4, 15.7 60.2, 15.3 60.2)))";
+		Object json = executeObject("return spatial.convert.wktToGeoJson($wkt) as json", Map.of("wkt", wkt), "json");
+		assertThat(json, equalTo(Map.of(
+				"type", "MultiPolygon",
+				"coordinates", List.of( // MultiPolygon
+						List.of( // Polygon
+								List.of( // LineString
+										List.of(15.3, 60.2),
+										List.of(15.3, 60.4),
+										List.of(15.7, 60.4),
+										List.of(15.7, 60.2),
+										List.of(15.3, 60.2)
+								)
+						)
+				)
+		)));
+	}
+}