[SEDONA-353] Add RS_BandNoDataValue

common/src/main/java/org/apache/sedona/common/raster/RasterBandAccessors.java

@@ -0,0 +1,38 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package org.apache.sedona.common.raster;
+
+import org.geotools.coverage.GridSampleDimension;
+import org.geotools.coverage.grid.GridCoverage2D;
+
+public class RasterBandAccessors {
+
+    public static Double getBandNoDataValue(GridCoverage2D raster, int band) {
+        if (band > raster.getNumSampleDimensions()) {
+            throw new IllegalArgumentException("Provided band index is not present in the raster");
+        }
+        GridSampleDimension bandSampleDimension = raster.getSampleDimension(band - 1);
+        if (bandSampleDimension.getNoDataValues() == null) return null;
+        return raster.getSampleDimension(band - 1).getNoDataValues()[0];
+    }
+
+    public static Double getBandNoDataValue(GridCoverage2D raster) {
+        return getBandNoDataValue(raster, 1);
+    }
+}

common/src/test/java/org/apache/sedona/common/raster/RasterBandAccessorsTest.java

@@ -0,0 +1,77 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+package org.apache.sedona.common.raster;
+
+import org.geotools.coverage.grid.GridCoverage2D;
+import org.junit.Test;
+import org.opengis.referencing.FactoryException;
+
+import java.io.IOException;
+
+import static org.junit.Assert.*;
+
+public class RasterBandAccessorsTest extends RasterTestBase {
+
+    @Test
+    public void testBandNoDataValueCustomBand() throws FactoryException {
+        int width = 5, height = 10;
+        GridCoverage2D emptyRaster = RasterConstructors.makeEmptyRaster(1, width, height, 53, 51, 1, 1, 0, 0, 4326);
+        double[] values = new double[width * height];
+        for (int i = 0; i < values.length; i++) {
+            values[i] = i + 1;
+        }
+        emptyRaster = MapAlgebra.addBandFromArray(emptyRaster, values, 2, 1d);
+        assertNotNull(RasterBandAccessors.getBandNoDataValue(emptyRaster, 2));
+        assertEquals(1, RasterBandAccessors.getBandNoDataValue(emptyRaster, 2), 1e-9);
+        assertNull(RasterBandAccessors.getBandNoDataValue(emptyRaster));
+    }
+
+    @Test
+    public void testBandNoDataValueDefaultBand() throws FactoryException {
+        int width = 5, height = 10;
+        GridCoverage2D emptyRaster = RasterConstructors.makeEmptyRaster(1, width, height, 53, 51, 1, 1, 0, 0, 4326);
+        double[] values = new double[width * height];
+        for (int i = 0; i < values.length; i++) {
+            values[i] = i + 1;
+        }
+        emptyRaster = MapAlgebra.addBandFromArray(emptyRaster, values, 1, 1d);
+        assertNotNull(RasterBandAccessors.getBandNoDataValue(emptyRaster));
+        assertEquals(1, RasterBandAccessors.getBandNoDataValue(emptyRaster), 1e-9);
+    }
+
+    @Test
+    public void testBandNoDataValueDefaultNoData() throws FactoryException {
+        int width = 5, height = 10;
+        GridCoverage2D emptyRaster = RasterConstructors.makeEmptyRaster(1, width, height, 53, 51, 1, 1, 0, 0, 4326);
+        double[] values = new double[width * height];
+        for (int i = 0; i < values.length; i++) {
+            values[i] = i + 1;
+        }
+        assertNull(RasterBandAccessors.getBandNoDataValue(emptyRaster, 1));
+    }
+
+    @Test
+    public void testBandNoDataValueIllegalBand() throws FactoryException, IOException {
+        GridCoverage2D raster = rasterFromGeoTiff(resourceFolder + "raster/raster_with_no_data/test5.tiff");
+        IllegalArgumentException exception = assertThrows(IllegalArgumentException.class, () -> RasterBandAccessors.getBandNoDataValue(raster, 2));
+        assertEquals("Provided band index is not present in the raster", exception.getMessage());
+    }
+
+}

docs/api/sql/Raster-operators.md

@@ -309,6 +309,38 @@ Output: `3`
 !!!Tip
     For non-skewed rasters, you can provide any value for longitude and the intended value of world latitude, to get the desired answer
 
+## Raster Band Accessors
+
+### RS_BandNoDataValue
+
+Introduction: Returns the no data value of the given band of the given raster. If no band is given, band 1 is assumed. The band parameter is 1-indexed. If there is no no data value associated with the given band, RS_BandNoDataValue returns null.
+
+!!!Note
+    If the given band does not lie in the raster, RS_BandNoDataValue throws an IllegalArgumentException
+
+Format: `RS_BandNoDataValue (raster: Raster, band: Int = 1)`
+
+Since: `1.5.0`
+
+Spark SQL example:
+```sql
+SELECT RS_BandNoDataValue(raster, 1) from rasters;
+```
+
+Output: `0.0`
+
+```sql
+SELECT RS_BandNoDataValue(raster) from rasters_without_nodata;
+```
+
+Output: `null`
+
+```sql
+SELECT RS_BandNoDataValue(raster, 3) from rasters;
+```
+
+Output: `IllegalArgumentException: Provided band index is not present in the raster.`
+
 
 ## Raster based operators
 

sql/common/src/main/scala/org/apache/sedona/sql/UDF/Catalog.scala

@@ -222,7 +222,8 @@ object Catalog {
     function[RS_Contains](),
     function[RS_WorldToRasterCoord](),
     function[RS_WorldToRasterCoordX](),
-    function[RS_WorldToRasterCoordY]()
+    function[RS_WorldToRasterCoordY](),
+    function[RS_BandNoDataValue]()
   )
 
   val aggregateExpressions: Seq[Aggregator[Geometry, Geometry, Geometry]] = Seq(

sql/common/src/main/scala/org/apache/spark/sql/sedona_sql/expressions/raster/RasterAccessors.scala

@@ -18,7 +18,7 @@
  */
 package org.apache.spark.sql.sedona_sql.expressions.raster
 
-import org.apache.sedona.common.raster.{GeometryFunctions, RasterAccessors}
+import org.apache.sedona.common.raster.RasterAccessors
 import org.apache.spark.sql.catalyst.expressions.Expression
 import org.apache.spark.sql.sedona_sql.expressions.InferrableFunctionConverter._
 import org.apache.spark.sql.sedona_sql.expressions.InferredExpression

sql/common/src/main/scala/org/apache/spark/sql/sedona_sql/expressions/raster/RasterBandAccessors.scala

@@ -0,0 +1,32 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+package org.apache.spark.sql.sedona_sql.expressions.raster
+
+import org.apache.sedona.common.raster.RasterBandAccessors
+import org.apache.spark.sql.catalyst.expressions.Expression
+import org.apache.spark.sql.sedona_sql.expressions.InferrableFunctionConverter._
+import org.apache.spark.sql.sedona_sql.expressions.InferredExpression
+
+case class RS_BandNoDataValue(inputExpressions: Seq[Expression]) extends InferredExpression(inferrableFunction2(RasterBandAccessors.getBandNoDataValue), inferrableFunction1(RasterBandAccessors.getBandNoDataValue)) {
+  protected def withNewChildrenInternal(newChildren: IndexedSeq[Expression]) = {
+    copy(inputExpressions = newChildren)
+  }
+}
+

sql/common/src/test/scala/org/apache/sedona/sql/rasteralgebraTest.scala

@@ -21,7 +21,7 @@ package org.apache.sedona.sql
 import org.apache.spark.sql.connector.catalog.TableChange.ColumnPosition.first
 import org.apache.spark.sql.functions.{collect_list, expr}
 import org.geotools.coverage.grid.GridCoverage2D
-import org.junit.Assert.assertEquals
+import org.junit.Assert.{assertEquals, assertNull}
 import org.locationtech.jts.geom.{Coordinate, Geometry}
 import org.scalatest.{BeforeAndAfter, GivenWhenThen}
 
@@ -671,5 +671,27 @@ class rasteralgebraTest extends TestBaseScala with BeforeAndAfter with GivenWhen
       assert(sparkSession.sql("SELECT RS_WITHIN(RS_MakeEmptyRaster(1, 20, 20, 2, 22, 1), ST_GeomFromWKT('POLYGON ((0 0, 0 50, 100 50, 100 0, 0 0))'))").first().getBoolean(0))
       assert(!sparkSession.sql("SELECT RS_WITHIN(RS_MakeEmptyRaster(1, 100, 100, 0, 50, 1), ST_GeomFromWKT('POLYGON ((2 2, 2 25, 20 25, 20 2, 2 2))'))").first().getBoolean(0))
     }
+
+    it("Passed RS_BandNoDataValue - noDataValueFor for raster from geotiff - default band") {
+      var df = sparkSession.read.format("binaryFile").load(resourceFolder + "raster/raster_with_no_data/test5.tiff")
+      df = df.selectExpr("RS_FromGeoTiff(content) as raster")
+      val result = df.selectExpr("RS_BandNoDataValue(raster)").first().getDouble(0)
+      assertEquals(0, result, 1e-9)
+    }
+
+    it("Passed RS_BandNoDataValue - null noDataValueFor for raster from geotiff") {
+      var df = sparkSession.read.format("binaryFile").load(resourceFolder + "raster/test1.tiff")
+      df = df.selectExpr("RS_FromGeoTiff(content) as raster")
+      val result = df.selectExpr("RS_BandNoDataValue(raster)").first().get(0)
+      assertNull(result)
+    }
+
+    it("Passed RS_BandNoDataValue - noDataValueFor for raster from geotiff - explicit band") {
+      var df = sparkSession.read.format("binaryFile").load(resourceFolder + "raster/raster_with_no_data/test5.tiff")
+      df = df.selectExpr("RS_FromGeoTiff(content) as raster")
+      val result = df.selectExpr("RS_BandNoDataValue(raster, 1)").first().getDouble(0)
+      assertEquals(0, result, 1e-9)
+    }
+
   }
 }