ZIO LMDB simple example / published by https://github.com/dacr/code-examples-manager #5c5fabdd-7f05-48d6-ae67-c8618b02284e/cc000abfc125180c0fd31e1573008fe900473514

zio-lmdb-basic.sc

//> using scala  "3.2.0"
//> using javaOpt "--add-opens", "java.base/java.nio=ALL-UNNAMED", "--add-opens", "java.base/sun.nio.ch=ALL-UNNAMED"
//> using lib "fr.janalyse::zio-lmdb:0.0.1"
//> using lib "fr.janalyse::zio-worksheet:2.0.2.0"
// ---------------------

import zio.*
import zio.lmdb.*
import zio.json.*
import java.io.File
import java.util.UUID
//import zio.worksheet.*

case class Record(uuid: UUID, name: String, age: Int)
object Record {
  given JsonCodec[Record] = DeriveJsonCodec.gen
}

object SimpleExample extends ZIOAppDefault {
  val dbConfig = ZLayer.fromZIO(
    for {
      dataPath    <- System.env("LMDB_DATA_PATH").someOrElse("lmdb-data-simple-example")
      dataPathFile = new File(dataPath)
      _           <- ZIO.attempt(dataPathFile.mkdirs())
    } yield LMDBConfig(dataPathFile)
  )

  override def run = example.provide(dbConfig, LMDB.live, Scope.default)

  val example = for {
    _        <- LMDB.databaseCreate("example")
    recordId <- Random.nextUUID
    record    = Record(recordId, "John Doe", 42)
    _        <- LMDB.upsertOverwrite("example", recordId.toString, record)
    gotten   <- LMDB.fetch[Record]("example", recordId.toString).some
    _        <- LMDB.delete("example", recordId.toString)
    deleted  <- LMDB.fetch[Record]("example", recordId.toString)
    _        <- Console.printLine(gotten)
  } yield ()
}

SimpleExample.main(Array.empty)