One way to do transactions in Play with Anorm

Article.scala

case class Article(...);

object Article {
  import DBUtil._

  def delete(id: Long): Either[String, Boolean] = {
    withTransaction { implicit connection =>
      SQL("DELETE FROM comments WHERE article_id = {id}").on("id" -> id).executeUpdate()
      SQL("DELETE FROM appusers WHERE id = {id}").on("id" -> id).executeUpdate( )
      Right(true)
    }
  }
}

DBUtil.scala

object DBUtil {

  def withTransaction[T](code: java.sql.Connection => Either[String,T]): Either[String, T] = {
    val connection = play.db.DB.getConnection
    val autoCommit = connection.getAutoCommit

    try {
      connection.setAutoCommit(false)
      result = code(connection)
      result.fold(
        { error  => throw new Exception(error) },
        { _      => connection.commit() }
      )

      result
    }

    catch {
      case e: Throwable =>
        connection.rollback()
        val msg = "Error, rolling back transaction: " + e.getMessage
        Logger.error(msg)
        Left(msg)
    }

    finally {
      connection.setAutoCommit(autoCommit)
    }
  }
}

Anorm doesn't provide a built-in way to handle database transactions, but the code in TransactionUtil.scala, above, appears to get the job done. It assumes the caller will pass a block of code that returns Left(errorMessage) on error and Right(something: T) on success. Article.scala shows an example of its use.