如何在Scala Spark中对某些列进行分组，并以JSON字符串的形式获取整行？

import org.apache.spark.sql.{SparkSession, functions}
import org.apache.spark.sql.functions._

val spark = SparkSession.builder()
  .appName("Spark GroupBy Example")
  .master("local")
  .getOrCreate()

val df = spark.read
  .format("csv")
  .option("header", "true")
  .load("path/to/input/file.csv")

val groupedDF = df.groupBy("column1", "column2")
  .agg(collect_list(struct(df.columns.map(col): _*)).as("rows"))

val resultDF = groupedDF.select(to_json(struct(groupedDF.columns.map(col): _*)).as("json"))

resultDF.write
  .format("json")
  .mode("overwrite")
  .save("path/to/output/directory")