ZIO LMDB simple example / published by https://github.com/dacr/code-examples-manager #5c5fabdd-7f05-48d6-ae67-c8618b02284e/d70f0fc7a34e5ed50b874732d34d5a570aa6b3aa

zio-lmdb-basic.sc

// summary : ZIO LMDB simple example
// keywords : scala, zio, lmdb, @testable
// publish : gist
// authors : David Crosson
// license : Apache License Version 2.0 (https://www.apache.org/licenses/LICENSE-2.0.txt)
// id : 5c5fabdd-7f05-48d6-ae67-c8618b02284e
// created-on : 2022-08-09T20:01:37+02:00
// managed-by : https://github.com/dacr/code-examples-manager
// run-with : scala-cli $file

// ---------------------
//> using scala 3.8.1
//> using dep fr.janalyse::zio-lmdb:2.3.2
//> using javaOpt --add-opens java.base/java.nio=ALL-UNNAMED --add-opens java.base/sun.nio.ch=ALL-UNNAMED
// ---------------------

import zio.*, zio.json.*, zio.lmdb.*, zio.lmdb.json.*
import java.io.File, java.util.UUID, java.time.OffsetDateTime

case class Record(uuid: UUID, name: String, age: Int, addedOn: OffsetDateTime) derives LMDBCodecJson

object SimpleExample extends ZIOAppDefault {
  override def run = example.provide(LMDB.liveWithDatabaseName("lmdb-data-simple-example"), Scope.default)

  val collectionName = "examples"
  val example        = for {
    examples  <- LMDB.collectionCreate[UUID,Record](collectionName, failIfExists = false)
    recordId  <- Random.nextUUID
    dateTime  <- Clock.currentDateTime
    record     = Record(recordId, "John Doe", 42, dateTime)
    _         <- examples.upsertOverwrite(recordId, record)
    gotten    <- examples.fetch(recordId).some
    collected <- examples.collect()
    _         <- Console.printLine(s"collection $collectionName contains ${collected.size} records")
    _         <- ZIO.foreachDiscard(collected)(record => Console.printLine(record))
    _         <- Console.printLine("""LMDB standard tools can be used to manage the database content : sudo apt-get install lmdb-utils""")
    _         <- Console.printLine(s"""To get some statistics     : mdb_stat -s $collectionName ${examples.lmdb.databasePath}/""")
    _         <- Console.printLine(s"""To dump collection content : mdb_dump -p -s $collectionName ${examples.lmdb.databasePath}/""")
  } yield ()
}

SimpleExample.main(Array.empty)