Playing around with caching with Cats Effect

SimpleCache.scala

final case class SimpleCache() {
  private def tempDir(key: String): IO[Path] =
    IO.fromTry(Try(System.getProperty("java.io.tmpdir")).map(s => Paths.get(s, key)))

  private def serialize[V](path: Path)(v: V): Unit = {
    val out = new ObjectOutputStream(new FileOutputStream(path.toString))
    out.writeObject(v)
    out.close()
  }

  private def deserialize[V](path: Path): V = {
    val in = new ObjectInputStream(new FileInputStream(path.toString))
    val obj = in.readObject()
    in.close()
    obj.asInstanceOf[V]
  }

  def fetch[V](key: String)(f: => IO[V]): IO[V] =
    for {
      cachePath <- tempDir(s"cache-${key}")
      result <- IO(cachePath.toFile.exists()).flatMap {
        case true =>
          IO.println(s"Loading from path ${cachePath}") *>
            IO(deserialize[V](cachePath))
        case false =>
          f.map { value =>
            serialize[V](cachePath)(value)
            value
          }
      }
    } yield result
}