Add ST_InteriorRings and ST_InteriorRingN functions

presto-docs/src/main/sphinx/functions/geospatial.rst

@@ -178,6 +178,14 @@ Accessors
     Singular geometries (e.g., POINT, LINESTRING, POLYGON), are treated as collections of one element.
     Empty geometries are treated as empty collections.
 
+.. function:: ST_InteriorRingN(Geometry, index) -> Geometry
+
+   Returns the interior ring element at the specified index (indices start at 1). If
+   the given index is less than 1 or greater than the total number of interior rings
+   in the input geometry, returns ``NULL``. Throws an error if the input geometry is
+   not a polygon.
+   Use :func:``ST_NumInteriorRing`` to find out the total number of elements.
+
 .. function:: ST_GeometryType(Geometry) -> varchar
 
     Returns the type of the geometry.
@@ -254,6 +262,12 @@ Accessors
 
     Return the Y coordinate of the point.
 
+.. function:: ST_InteriorRings(Geometry) -> Geometry
+
+   Returns an array of all interior rings found in the input geometry, or an empty
+   array if the polygon has no interior rings. Returns null if the input geometry
+   is empty. Throws an error if the input geometry is not a polygon.
+
 .. function:: ST_NumGeometries(Geometry) -> bigint
 
     Returns the number of geometries in the collection.

presto-geospatial/src/main/java/com/facebook/presto/plugin/geospatial/GeoFunctions.java

@@ -481,6 +481,26 @@ public static Long stNumInteriorRings(@SqlType(GEOMETRY_TYPE_NAME) Slice input)
         return Long.valueOf(((OGCPolygon) geometry).numInteriorRing());
     }
 
+    @SqlNullable
+    @Description("Returns an array of interior rings of a polygon")
+    @ScalarFunction("ST_InteriorRings")
+    @SqlType("array(" + GEOMETRY_TYPE_NAME + ")")
+    public static Block stInteriorRings(@SqlType(GEOMETRY_TYPE_NAME) Slice input)
+    {
+        OGCGeometry geometry = deserialize(input);
+        validateType("ST_InteriorRings", geometry, EnumSet.of(POLYGON));
+        if (geometry.isEmpty()) {
+            return null;
+        }
+
+        OGCPolygon polygon = (OGCPolygon) geometry;
+        BlockBuilder blockBuilder = GEOMETRY.createBlockBuilder(null, polygon.numInteriorRing());
+        for (int i = 0; i < polygon.numInteriorRing(); i++) {
+            GEOMETRY.writeSlice(blockBuilder, serialize(polygon.interiorRingN(i)));
+        }
+        return blockBuilder.build();
+    }
+
     @Description("Returns the cardinality of the geometry collection")
     @ScalarFunction("ST_NumGeometries")
     @SqlType(StandardTypes.INTEGER)
@@ -568,7 +588,6 @@ public static Slice stPointN(@SqlType(GEOMETRY_TYPE_NAME) Slice input, @SqlType(
     public static Block stGeometries(@SqlType(GEOMETRY_TYPE_NAME) Slice input)
     {
         OGCGeometry geometry = deserialize(input);
-
         if (geometry.isEmpty()) {
             return null;
         }
@@ -585,10 +604,25 @@ public static Block stGeometries(@SqlType(GEOMETRY_TYPE_NAME) Slice input)
         for (int i = 0; i < collection.numGeometries(); i++) {
             GEOMETRY.writeSlice(blockBuilder, serialize(collection.geometryN(i)));
         }
-
         return blockBuilder.build();
     }
 
+    @SqlNullable
+    @Description("Returns the interior ring element at the specified index (indices start at 1)")
+    @ScalarFunction("ST_InteriorRingN")
+    @SqlType(GEOMETRY_TYPE_NAME)
+    public static Slice stInteriorRingN(@SqlType(GEOMETRY_TYPE_NAME) Slice input, @SqlType(INTEGER) long index)
+    {
+        OGCGeometry geometry = deserialize(input);
+        validateType("ST_InteriorRingN", geometry, EnumSet.of(POLYGON));
+        OGCPolygon polygon = (OGCPolygon) geometry;
+        if (index < 1 || index > polygon.numInteriorRing()) {
+            return null;
+        }
+        OGCGeometry interiorRing = polygon.interiorRingN(toIntExact(index) - 1);
+        return serialize(interiorRing);
+    }
+
     @Description("Returns the number of points in a Geometry")
     @ScalarFunction("ST_NumPoints")
     @SqlType(StandardTypes.BIGINT)

presto-geospatial/src/test/java/com/facebook/presto/plugin/geospatial/TestGeoFunctions.java

@@ -750,6 +750,33 @@ public void testGreatCircleDistance()
         assertInvalidFunction("great_circle_distance(36.12, -86.67, 33.94, infinity())", "Longitude must be between -180 and 180");
     }
 
+    @Test
+    public void testSTInteriorRings()
+    {
+        assertInvalidInteriorRings("POINT (2 3)", "POINT");
+        assertInvalidInteriorRings("LINESTRING EMPTY", "LINE_STRING");
+        assertInvalidInteriorRings("MULTIPOINT (30 20, 60 70)", "MULTI_POINT");
+        assertInvalidInteriorRings("MULTILINESTRING ((1 10, 100 1000), (2 2, 1 0, 5 6))", "MULTI_LINE_STRING");
+        assertInvalidInteriorRings("MULTIPOLYGON (((1 1, 1 3, 3 3, 3 1)), ((0 0, 0 2, 2 2, 2 0)))", "MULTI_POLYGON");
+        assertInvalidInteriorRings("GEOMETRYCOLLECTION (POINT (1 1), POINT (2 3), LINESTRING (5 8, 13 21))", "GEOMETRY_COLLECTION");
+
+        assertFunction("ST_InteriorRings(ST_GeometryFromText('POLYGON EMPTY'))", new ArrayType(GEOMETRY), null);
+        assertInteriorRings("POLYGON ((0 0, 1 0, 1 1, 0 1, 0 0))");
+        assertInteriorRings("POLYGON ((0 0, 0 3, 3 3, 3 0, 0 0), (1 1, 1 2, 2 2, 2 1, 1 1))", "LINESTRING (1 1, 1 2, 2 2, 2 1, 1 1)");
+        assertInteriorRings("POLYGON ((0 0, 0 5, 5 5, 5 0, 0 0), (1 1, 1 2, 2 2, 2 1, 1 1), (3 3, 3 4, 4 4, 4 3, 3 3))",
+                "LINESTRING (1 1, 1 2, 2 2, 2 1, 1 1)", "LINESTRING (3 3, 3 4, 4 4, 4 3, 3 3)");
+    }
+
+    private void assertInteriorRings(String wkt, String... expected)
+    {
+        assertFunction(format("transform(ST_InteriorRings(ST_GeometryFromText('%s')), x -> ST_ASText(x))", wkt), new ArrayType(VARCHAR), ImmutableList.copyOf(expected));
+    }
+
+    private void assertInvalidInteriorRings(String wkt, String geometryType)
+    {
+        assertInvalidFunction(format("ST_InteriorRings(ST_GeometryFromText('%s'))", wkt), format("ST_InteriorRings only applies to POLYGON. Input type is: %s", geometryType));
+    }
+
     @Test
     public void testSTNumGeometries()
     {
@@ -943,6 +970,33 @@ private void assertSTGeometries(String wkt, String... expected)
         assertFunction(String.format("transform(ST_Geometries(ST_GeometryFromText('%s')), x -> ST_ASText(x))", wkt), new ArrayType(VARCHAR), ImmutableList.copyOf(expected));
     }
 
+    public void testSTInteriorRingN()
+    {
+        assertInvalidInteriorRingN("POINT EMPTY", 0, "POINT");
+        assertInvalidInteriorRingN("LINESTRING (1 2, 2 3, 3 4)", 1, "LINE_STRING");
+        assertInvalidInteriorRingN("MULTIPOINT (1 1, 2 3, 5 8)", -1, "MULTI_POINT");
+        assertInvalidInteriorRingN("MULTILINESTRING ((2 4, 4 2), (3 5, 5 3))", 0, "MULTI_LINE_STRING");
+        assertInvalidInteriorRingN("MULTIPOLYGON (((1 1, 1 3, 3 3, 3 1)), ((2 4, 2 6, 6 6, 6 4)))", 2, "MULTI_POLYGON");
+        assertInvalidInteriorRingN("GEOMETRYCOLLECTION (POINT (2 2), POINT (10 20))", 1, "GEOMETRY_COLLECTION");
+
+        assertInteriorRingN("POLYGON ((0 0, 1 0, 1 1, 0 1, 0 0))", 1, null);
+        assertInteriorRingN("POLYGON ((0 0, 1 0, 1 1, 0 1, 0 0))", 2, null);
+        assertInteriorRingN("POLYGON ((0 0, 1 0, 1 1, 0 1, 0 0))", -1, null);
+        assertInteriorRingN("POLYGON ((0 0, 1 0, 1 1, 0 1, 0 0))", 0, null);
+        assertInteriorRingN("POLYGON ((0 0, 0 3, 3 3, 3 0, 0 0), (1 1, 1 2, 2 2, 2 1, 1 1))", 1, "LINESTRING (1 1, 1 2, 2 2, 2 1, 1 1)");
+        assertInteriorRingN("POLYGON ((0 0, 0 5, 5 5, 5 0, 0 0), (1 1, 1 2, 2 2, 2 1, 1 1), (3 3, 3 4, 4 4, 4 3, 3 3))", 2, "LINESTRING (3 3, 3 4, 4 4, 4 3, 3 3)");
+    }
+
+    private void assertInteriorRingN(String wkt, int index, String expected)
+    {
+        assertFunction(format("ST_ASText(ST_InteriorRingN(ST_GeometryFromText('%s'), %d))", wkt, index), VARCHAR, expected);
+    }
+
+    private void assertInvalidInteriorRingN(String wkt, int index, String geometryType)
+    {
+        assertInvalidFunction(format("ST_InteriorRingN(ST_GeometryFromText('%s'), %d)", wkt, index), format("ST_InteriorRingN only applies to POLYGON. Input type is: %s", geometryType));
+    }
+
     public void testSTGeometryType()
     {
         assertFunction("ST_GeometryType(ST_Point(1, 4))", VARCHAR, "ST_Point");