[SPARK-33134] Incorrect nested complex JSON fields raise an exception

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 3.0.2, 3.1.0
• Fix Version/s: 3.0.2, 3.1.0
• Component/s: SQL
• Assignee: Max Gekk
• Reporter: Max Gekk
• Created: 13/Oct/20 13:07
• Updated: 12/Dec/22 18:10
• Resolved: 14/Oct/20 03:14

Description

The code below:

val pokerhand_raw = Seq("""[{"cards": [19], "playerId": 123456}]""").toDF("events")
    val event = new StructType()
      .add("playerId", LongType)
      .add("cards", ArrayType(
        new StructType()
          .add("id", LongType)
          .add("rank", StringType)))
    val pokerhand_events = pokerhand_raw
      .select(explode(from_json($"events", ArrayType(event))).as("event"))
    pokerhand_events.show

throw the exception in the PERMISSIVE mode (default):

Caused by: java.lang.ClassCastException: java.lang.Long cannot be cast to org.apache.spark.sql.catalyst.util.ArrayData
  at org.apache.spark.sql.catalyst.expressions.BaseGenericInternalRow.getArray(rows.scala:48)
  at org.apache.spark.sql.catalyst.expressions.BaseGenericInternalRow.getArray$(rows.scala:48)
  at org.apache.spark.sql.catalyst.expressions.GenericInternalRow.getArray(rows.scala:195)
  at org.apache.spark.sql.catalyst.expressions.JsonToStructs.$anonfun$converter$2(jsonExpressions.scala:560)
  at org.apache.spark.sql.catalyst.expressions.JsonToStructs.nullSafeEval(jsonExpressions.scala:597)
  at org.apache.spark.sql.catalyst.expressions.UnaryExpression.eval(Expression.scala:461)
  at org.apache.spark.sql.catalyst.expressions.ExplodeBase.eval(generators.scala:313)
  at org.apache.spark.sql.execution.GenerateExec.$anonfun$doExecute$8(GenerateExec.scala:108)

The same works in Spark 2.4:

Welcome to
      ____              __
     / __/__  ___ _____/ /__
    _\ \/ _ \/ _ `/ __/  '_/
   /___/ .__/\_,_/_/ /_/\_\   version 2.4.6
      /_/

Using Scala version 2.11.12 (OpenJDK 64-Bit Server VM, Java 1.8.0_265)
...
scala> pokerhand_events.show()
+-----+
|event|
+-----+
+-----+

Issue Links

• is related to: SPARK-40646 Fix returning partial results in JSON data source and JSON functions
• links to: [Github] Pull Request #30031 (MaxGekk)
• links to: [Github] Pull Request #30031 (MaxGekk)
• links to: [Github] Pull Request #30032 (MaxGekk)