Creating a database interface
In the previous section, we looked at how we can use a configuration manager library such as PureConfig to read environment variables. However, the getDBParams function is not very useful as this needs to be repeated each time we need to access the host, port, and so on for a given database. One possible option would be to update getDBParams by passing a Database object instead, as shown here:
package com.packt.dewithscala.chapter4
import org.apache.spark.sql.SparkSession
import com.packt.dewithscala.Config
import com.packt.dewithscala._
@SuppressWarnings(Array("org.wartremover.warts.OptionPartial"))
object UpdatedDBParamMethod extends App {
  private val session = SparkSession
    .builder()
    .appName("de-with-scala")
    .master("local[*]")
    .getOrCreate()
  private val mysqlDB = Config.getDB("my_db").get...
