How do you project geometries from one EPSG to another with Spark/Geomesa? - apache-spark

Question

I am "translating" some Postgis code to Geomesa and I have some Postgis code like this:
select ST_Transform(ST_SetSRID(ST_Point(longitude, latitude), 4326), 27700)
which converts a point geometry from 4326 to 27700 for example.
On Geomesa-Spark-sql documentation https://www.geomesa.org/documentation/user/spark/sparksql_functions.html I can see ST_Point but I cannot find any equivalent ST_Transform function. Any idea?

Answer 1

I have used sedona library for the geoprocessing and it has the st_transform
function which I have used and working fine so if you want you can use it. Please find below link for the official documentation - https://sedona.apache.org/api/sql/GeoSparkSQL-Function/#st_transform
Even Geomesa is now supporting the function -
https://www.geomesa.org/documentation/3.1.2/user/spark/sparksql_functions.html#st-transform

Answer 2

For GeoMesa 1.x, 2.x, and the upcoming 3.0 release, there is not an ST_Transform presently. One could make their own UDF using GeoTools (or another library) to do the transformation.
Admittedly, this would require some work.

Answer 3

I recently run with the same issue on Azure Databricks. I was able to do it manually installing the JAR library from here.
And then running the following Scala code.
%scala
import org.locationtech.jts.geom._
import org.locationtech.geomesa.spark.jts._
import org.locationtech.geomesa.spark.geotools._
import org.apache.spark.sql.types._
import org.apache.spark.sql.functions._
import spark.implicits._
spark.withJTS
data_points = (
data_points
.withColumn("geom", st_makePoint(col("LONGITUDE"), col("LATITUDE")))
.withColumn("geom_5347", st_transform(col("geom"), lit("EPSG:4326"), lit("EPSG:5347")))
)
display(data_points)
Good luck.