Spark job to read gzip files, ignoring corrupted files

FilterBadGzipFiles.scala

import java.io._
import scala.io._
import java.util.zip._

// Spark
import org.slf4j.Logger
import org.apache.spark.{ SparkConf, SparkContext, Logging }

// Hadoop
import org.apache.hadoop.io.compress.GzipCodec

object FilterBadGzipFiles extends Logging {
  def main(args: Array[String]): Unit = {
    val sparkConf = new SparkConf()
    val sc = new SparkContext(sparkConf)

    val files = sc.binaryFiles(args(0))

    val lines =
      files.flatMap {
        case (path, stream) =>
          try {
            val is =
              if (path.toLowerCase.endsWith(".gz"))
                new GZIPInputStream(stream.open)
              else
                stream.open

            try {
              Source.fromInputStream(is).getLines.toList
            } finally {
              try { is.close } catch { case _: Throwable => }
            }
          } catch {
            case e: Throwable =>
              log.warn(s"error reading from ${path}: ${e.getMessage}", e)
              List.empty[String]
          }
      }

    lines.saveAsTextFile(args(1), classOf[GzipCodec])
  }
}