LaserDisc

LaserDisc is a Scala client for Redis and for servers that speak the same protocol, such as Valkey, KeyDB and Dragonfly.

Every command takes arguments whose types only accept valid values, so a key can't be empty and a port can't be out of range. Mistakes in literal values are caught when your code compiles, and you choose the type each reply is read into.

LaserDisc works with Scala 2.12, 2.13 and 3.9 or newer, on Java 17 or newer.

Module	What it gives you	JVM	Scala.js	Scala Native
`laserdisc-core`	Commands and the Redis wire format	✓	✓	✓
`laserdisc-fs2`	A client built on fs2 and Cats Effect	✓	✓	✓
`laserdisc-circe`	Store and read values as JSON with circe	✓	✓	✓
`laserdisc-cli`	An interactive prompt, like `redis-cli`	✓	✓	✓

With Redis running on localhost:6379:

import cats.effect.{IO, IOApp}
import log.effect.LogWriter
import log.effect.fs2.SyncLogWriter

import laserdisc.*
import laserdisc.redis_8_10.*
import laserdisc.auto.*
import laserdisc.fs2.*

object Main extends IOApp.Simple {
  implicit val logWriter: LogWriter[IO] = SyncLogWriter.consoleLog[IO]

  override val run: IO[Unit] =
    RedisClient[IO].to("localhost", 6379).use { client =>
      client.send(set("a", 23), get[PosInt]("a")).flatMap {
        case (Right(OK), Right(Some(a))) => IO.println(s"a is ${a.value}")
        case other                       => IO.raiseError(new RuntimeException(s"unexpected reply: $other"))
      }
    }
}

To add LaserDisc to your build, see Getting started.

Why the name

"A LaserDisc" is an anagram of "Scala Redis". LaserDiscs were also the first optical discs to offer random access, which suits a key-value store. More on Wikipedia.