ZIO LMDB simple example using configuration provider / published by https://github.com/dacr/code-examples-manager #ab2e9b2c-bdcc-4eab-ba9b-3ab3953429c7/58aed1d7f49deb7c1f7fc71141766bc68ac6c067

zio-lmdb-with-config.sc

// summary : ZIO LMDB simple example using configuration provider
// keywords : scala, zio, lmdb, @testable
// publish : gist
// authors : David Crosson
// license : Apache NON-AI License Version 2.0 (https://raw.githubusercontent.com/non-ai-licenses/non-ai-licenses/main/NON-AI-APACHE2)
// id : ab2e9b2c-bdcc-4eab-ba9b-3ab3953429c7
// created-on : 2023-04-29T22:48:17+02:00
// managed-by : https://github.com/dacr/code-examples-manager
// run-with : scala-cli $file

// ---------------------
//> using scala 3.6.4
//> using dep fr.janalyse::zio-lmdb:2.0.0
//> using dep dev.zio::zio-config:4.0.4
//> using dep dev.zio::zio-config-typesafe:4.0.4
//> using javaOpt --add-opens java.base/java.nio=ALL-UNNAMED --add-opens java.base/sun.nio.ch=ALL-UNNAMED
// ---------------------

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

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

object SimpleExample extends ZIOAppDefault {
  // Simulating a configuration, or use .fromResourcePath to automatically load configs from class path
  val configProvider =
    ConfigProvider.fromHoconString(
      input = s"""lmdb {
                 |  name = my-database
                 |  home = /tmp
                 |  sync = false
                 |  maxReaders = 10
                 |}
                 |""".stripMargin
    )

  override val bootstrap: ZLayer[ZIOAppArgs, Any, Any] = Runtime.setConfigProvider(configProvider)

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

  val collectionName = "examples"
  val example        = for {
    examples  <- LMDB.collectionCreate[Record](collectionName, failIfExists = false)
    recordId  <- Random.nextUUID
    dateTime  <- Clock.currentDateTime
    record     = Record(recordId, "John Doe", 42, dateTime)
    _         <- examples.upsertOverwrite(recordId.toString, record)
    gotten    <- examples.fetch(recordId.toString).some
    collected <- examples.collect()
    _         <- Console.printLine(s"collection $collectionName contains ${collected.size} records")
    _         <- ZIO.foreach(collected)(record => Console.printLine(record))
    lmdb      <- ZIO.service[LMDB]
    _         <- 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 ${lmdb.databasePath}/""")
    _         <- Console.printLine(s"""To dump collection content : mdb_dump -p -s $collectionName ${lmdb.databasePath}/""")
  } yield ()
}

SimpleExample.main(Array.empty)