Scala Dataframe - spark.cassandra.sql.pushdown.additionalClasses not working

[Arun Vigesh]

I am encountering a Singleton object not available error when trying to add the parameter spark.cassandra.sql.pushdown.additionalClasses to push all filters to Cassandra. Please find the code and error message below:

Code:

package com.common.reader

import org.apache.spark.sql.{DataFrame, SparkSession}
import com.datastax.spark.connector.cql.TableDef
import org.apache.spark.SparkConf
import org.apache.spark.sql.cassandra.{AnalyzedPredicates, CassandraPredicateRules, CassandraSourceRelation}

class CassandraReader(spark: SparkSession) {
  def read(table: String, keyspace: String, path: String, inc_field: String): DataFrame =
  {
    var df = spark
      .read
      .format("org.apache.spark.sql.cassandra")
      .option( "table",table)
      .option( "keyspace",keyspace)
 .option("spark.cassandra.sql.pushdown.additionalClasses","com.common.reader.PushdownEverything")
//      .options(Map(
//        "keyspace" -> keyspace,
//        "table" -> table,
//        "pushdown" -> "true",
//        CassandraSourceRelation.AdditionalCassandraPushDownRulesParam.name -> "com.common.reader.PushdownEverything"))
      .load
    if (inc_field.nonEmpty)
    {
      val max_inc_value= spark.sql(s"select max(${inc_field}) from delta.`${path}`").first.get(0)
      println(max_inc_value)
      df = df.filter(s"${inc_field}>'${max_inc_value}'")
    }
    df
  }
}
object PushdownEverything extends CassandraPredicateRules {
  override def apply(
                      predicates: AnalyzedPredicates,
                      tableDef: TableDef,
                      sparkConf: SparkConf): AnalyzedPredicates = {
    AnalyzedPredicates(predicates.handledByCassandra ++ predicates.handledBySpark, Set.empty)
  }
}

Error:

IllegalArgumentException: Singleton object not available: com.common.reader.PushdownEverything
Caused by: ClassNotFoundException: com.common.reader.PushdownEverything
at com.datastax.spark.connector.util.ReflectionUtil$.findGlobalObject(ReflectionUtil.scala:54)
at com.datastax.spark.connector.datasource.CassandraScanBuilder.$anonfun$additionalRules$1(CassandraScanBuilder.scala:102)
at scala.collection.TraversableLike.$anonfun$map$1(TraversableLike.scala:286)
at scala.collection.IndexedSeqOptimized.foreach(IndexedSeqOptimized.scala:36)
at scala.collection.IndexedSeqOptimized.foreach$(IndexedSeqOptimized.scala:33)
at scala.collection.mutable.ArrayOps$ofRef.foreach(ArrayOps.scala:198)
at scala.collection.TraversableLike.map(TraversableLike.scala:286)
at scala.collection.TraversableLike.map$(TraversableLike.scala:279)
at scala.collection.mutable.ArrayOps$ofRef.map(ArrayOps.scala:198)
at com.datastax.spark.connector.datasource.CassandraScanBuilder.additionalRules(CassandraScanBuilder.scala:102)
at com.datastax.spark.connector.datasource.CassandraScanBuilder.pushFilters(CassandraScanBuilder.scala:76)
at org.apache.spark.sql.execution.datasources.v2.PushDownUtils$.pushFilters(PushDownUtils.scala:66)
at org.apache.spark.sql.execution.datasources.v2.V2ScanRelationPushDown$$anonfun$pushDownFilters$1.applyOrElse(V2ScanRelationPushDown.scala:73)
at org.apache.spark.sql.execution.datasources.v2.V2ScanRelationPushDown$$anonfun$pushDownFilters$1.applyOrElse(V2ScanRelationPushDown.scala:60)
at org.apache.spark.sql.catalyst.trees.TreeNode.$anonfun$transformDownWithPruning$1(TreeNode.scala:465)
at org.apache.spark.sql.catalyst.trees.CurrentOrigin$.withOrigin(origin.scala:69)
at org.apache.spark.sql.catalyst.trees.TreeNode.transformDownWithPruning(TreeNode.scala:465)
at org.apache.spark.sql.catalyst.plans.logical.LogicalPlan.org$apache$spark$sql$catalyst$plans$logical$AnalysisHelper$$super$transformDownWithPruning(LogicalPlan.scala:39)
at org.apache.spark.sql.catalyst.plans.logical.AnalysisHelper.transformDownWithPruning(AnalysisHelper.scala:339)
at org.apache.spark.sql.catalyst.plans.logical.AnalysisHelper.transformDownWithPruning$(AnalysisHelper.scala:335)
at org.apache.spark.sql.catalyst.plans.logical.LogicalPlan.transformDownWithPruning(LogicalPlan.scala:39)
at org.apache.spark.sql.catalyst.plans.logical.LogicalPlan.transformDownWithPruning(LogicalPlan.scala:39)
at org.apache.spark.sql.catalyst.trees.TreeNode.$anonfun$transformDownWithPruning$3(TreeNode.scala:470)
at org.apache.spark.sql.catalyst.trees.UnaryLike.mapChildren(TreeNode.scala:1267)
at org.apache.spark.sql.catalyst.trees.UnaryLike.mapChildren$(TreeNode.scala:1266)
at org.apache.spark.sql.execution.datasources.WriteFiles.mapChildren(WriteFiles.scala:58)
at org.apache.spark.sql.catalyst.trees.TreeNode.transformDownWithPruning(TreeNode.scala:470)
at org.apache.spark.sql.catalyst.plans.logical.LogicalPlan.org$apache$spark$sql$catalyst$plans$logical$AnalysisHelper$$super$transformDownWithPruning(LogicalPlan.scala:39) ....