Redis write through cache for Scaliak (using Sedis)

gistfile1.scala

abstract class WriteThroughRedisDomainHelper[T <: DomainObject](override val clientPool: ScaliakPbClientPool, val redisPool: Pool)(implicit mo: Manifest[T]) extends DomainObjectHelper[T](clientPool) {
  override def fetch(k: String) = {
    redisPool.withClient { _.get(k) }.map { parse(_) }.successNel.pure[IO].except { _.failNel.pure[IO] }.flatMap { x ⇒
      ~x.toOption match {
        case Some(o) if (o != null) ⇒ x.pure[IO]
        case None ⇒ super.fetch(k)
      }
    }
  }
  
  override def store(o: T) = {
    for {
      riak <- super.store(o)
      _ <- redisPool.withClient(_.set(o.key, generate(o))).successNel.pure[IO].except { _.failNel.pure[IO] }
    } yield riak
  }
  
  override def delete(o: T) = {
    for {
      riak <- super.delete(o)
      _ <- redisPool.withJedisClient(_.set(o.key, null)).successNel.pure[IO].except { _.failNel.pure[IO] }
    } yield riak
  }
}