Packages

  • package root
  • package scala
  • package scodec
  • package skunk

    Skunk is a functional data access layer for Postgres.

    Skunk is a functional data access layer for Postgres.

    Design principles:

    • Skunk doesn't use JDBC. It speaks the Postgres wire protocol. It will not work with any other database back end.
    • Skunk is asynchronous all the way down, via cats-effect, fs2, and ultimately nio. The high-level network layers (Protocol and Session) are safe to use concurrently.
    • Serialization to and from schema types is not typeclass-based, so there are no implicit derivations. Codecs are explicit, like parser combinators.
    • I'm not sweating arity abstraction that much. Pass a ~ b ~ c for three args and Void if there are no args. This may change in the future but it's fine for now.
    • Skunk uses Resource for lifetime-managed objects, which means it takes some discipline to avoid leaks, especially when working concurrently. May or may not end up being problematic.
    • I'm trying to write good Scaladoc this time.

    A minimal example follows. We construct a Resource that yields a Session, then use it.

    package example
    
    import cats.effect._
    import skunk._
    import skunk.implicits._
    import skunk.codec.numeric._
    
    object Minimal extends IOApp {
    
      val session: Resource[IO, Session[IO]] =
        Session.single(
          host     = "localhost",
          port     = 5432,
          user     = "postgres",
          database = "world",
        )
    
      def run(args: List[String]): IO[ExitCode] =
        session.use { s =>
          for {
            n <- s.unique(sql"select 42".query(int4))
            _ <- IO(println(s"The answer is $n."))
          } yield ExitCode.Success
        }
    
    }

    Continue reading for an overview of the library. It's pretty small.

p

root package

package root

Ungrouped