Generate Hive schema from Spark Dataframe

generate_hive_schema.scala

import org.apache.spark.sql.DataFrame

def dataFrameToDDL(dataFrame: DataFrame, tableName: String): String = {
    val columns = dataFrame.schema.map { field =>
        "  " + field.name + " " + field.dataType.simpleString.toUpperCase
    }
    s"CREATE TABLE $tableName (\n${columns.mkString(",\n")}\n)"
}

import spark.sqlContext.implicits._

// Example of hierarchical structure:
case class Model(`type`: String)
case class Device(`type`: String, model: Model, serial: Long)
case class Event(device: Device, timestamp: Long)

val df = Seq(
    Event(Device("Android", Model("Huawei"), 1), 1525354897L)).toDF()

dataFrameToDDL(df, "events")