ZIO learning - testing slf4j logging bridge / published by https://github.com/dacr/code-examples-manager #b64f070c-3b27-414c-9587-943bc80bb335/d0b778bad0a0a99a3c44eb3e780f74e07b59d411

zio-learning-logging-4-example.sc

// summary : ZIO learning - testing slf4j logging bridge
// keywords : scala, zio, logging, slf4j, bridge, @testable
// publish : gist
// authors : David Crosson
// license : Apache2
// id : b64f070c-3b27-414c-9587-943bc80bb335
// created-on : 2023-09-08T16:30:50+02:00
// managed-by : https://github.com/dacr/code-examples-manager
// run-with : scala-cli $file

// ---------------------
//> using scala "3.4.2"
//> using dep "dev.zio::zio:2.0.16"
//> using dep "dev.zio::zio-logging-slf4j2-bridge:2.1.14"
// ---------------------

// initial example coming from package zio.logging.example

import zio.{LogAnnotation => LLogAnnotation, *}
import zio.logging.*

import java.util.UUID

object Slf4j2SimpleApp extends ZIOAppDefault {

  val logFilter: LogFilter[String] = LogFilter.logLevelByName(
    LogLevel.Info,
    "zio.logging.slf4j" -> LogLevel.Debug,
    "SLF4J-LOGGER"      -> LogLevel.Warning
  )

  val logConfig = ConsoleLoggerConfig(
    LogFormat.colored +
      LogFormat.space +
      LogFormat.label("name", LoggerNameExtractor.loggerNameAnnotationOrTrace.toLogFormat()) +
      LogFormat.space +
      LogFormat.logAnnotation(LogAnnotation.UserId) +
      LogFormat.space +
      LogFormat.logAnnotation(LogAnnotation.TraceId) +
      LogFormat.space +
      LogFormat.spans +
      LogFormat.space +
      LogFormat.default,
    logFilter
  )

  val loggerLayer = Runtime.removeDefaultLoggers >>> consoleJsonLogger(logConfig) >+> zio.logging.slf4j.bridge.Slf4jBridge.initialize
  // val loggerLayer = Runtime.removeDefaultLoggers >>> consoleLogger(logConfig) >+> zio.logging.slf4j.bridge.Slf4jBridge.initialize

  override val bootstrap: ZLayer[ZIOAppArgs, Any, Any] = loggerLayer

  private val users = List.fill(2)(UUID.randomUUID())

  def legacyCode1(message: String): Int = {
    val legacyLogger = org.slf4j.LoggerFactory.getLogger("LegacyLogger")
    legacyLogger.info(s"Hello lecacy1 code message=$message")
    42
  }

  def legacyCode2(greetings: String): Int = {
    import java.util.logging.*
    val legacyLogger = Logger.getLogger("LegacyLogger")
    legacyLogger.info(s"$greetings lecacy2 code")
    42 * 42
  }

  override def run: ZIO[Scope, Any, ExitCode] =
    for {
      _       <- ZIO.logInfo("Start")
      traceId <- ZIO.succeed(UUID.randomUUID())
      _       <- ZIO.foreachPar(users) { uId =>
                   ZIO.logSpan("some-processing") {
                     ZIO.logInfo("Starting user operation") *>
                       // ZIO.logInfo("Confidential user operation") @@ SLF4J.logMarkerName("CONFIDENTIAL") *>
                       ZIO.logSpan("legacyCode1") { ZIO.attempt(legacyCode1("Hello")) }
                       @@ ZIOAspect.logged *>
                       // ZIO.attempt(legacyCode2("Good morning")) *>
                       ZIO.sleep(500.millis) *>
                       ZIO.logInfo("Stopping user operation")
                   } @@ LogAnnotation.UserId(uId.toString)
                 } @@ LogAnnotation.TraceId(traceId) @@ zio.logging.loggerName("zio.logging.example.UserOperation")
      _       <- ZIO.logInfo("Done")
    } yield ExitCode.success
}

Slf4j2SimpleApp.main(Array.empty)