Fix st_reproject throws on encountering null value in column

Author: Netanel Malka <[email protected]>

st_reproject throws on encountering null value in column - #501

Added null check on ReprojectGeometry

Signed-off-by: Netanel Malka <[email protected]>

Author: netanel246

core/src/main/scala/org/locationtech/rasterframes/expressions/transformers/ReprojectGeometry.scala

@@ -82,8 +82,13 @@ case class ReprojectGeometry(geometry: Expression, srcCRS: Expression, dstCRS: E
       // Optimized pass-through case.
       case (s: LazyCRS, r: LazyCRS) if s.encoded == r.encoded => geometry.eval(input)
       case _ =>
-        val geom = JTSTypes.GeometryTypeInstance.deserialize(geometry.eval(input))
-        JTSTypes.GeometryTypeInstance.serialize(reproject(geom, src, dst))
+        if (geometry.eval(input) != null) {
+          val geom = JTSTypes.GeometryTypeInstance.deserialize(geometry.eval(input))
+          JTSTypes.GeometryTypeInstance.serialize(reproject(geom, src, dst))
+        }
+        else {
+          null
+        }
     }
   }
 }

core/src/test/scala/org/locationtech/rasterframes/ReprojectGeometrySpec.scala

@@ -22,6 +22,7 @@
 package org.locationtech.rasterframes
 
 import geotrellis.proj4.{CRS, LatLng, Sinusoidal, WebMercator}
+import org.apache.spark.sql.functions.lit
 import org.apache.spark.sql.Encoders
 import org.locationtech.jts.geom._
 
@@ -118,5 +119,15 @@ class ReprojectGeometrySpec extends TestEnvironment {
 
       checkDocs("st_reproject")
     }
+
+    it("should work on null columns") {
+      val df = Seq(1, 2, 3).toDF("id")
+
+      noException shouldBe thrownBy {
+        df.withColumn("nullId", lit(null))
+          .select(st_reproject(st_makePoint($"nullId", $"nullId"), WebMercator, Sinusoidal))
+          .count()
+      }
+    }
   }
 }