LEGO · hejfelix · Mar 10, 2023 · Mar 6, 2023 · Mar 6, 2023 · Mar 6, 2023
diff --git a/README.md b/README.md
@@ -26,11 +26,12 @@ A **pure** _(in both senses of the word!)_ **Scala 3** logging library with **no
 
 ### Cross platform
 
-| Module | JVM | scala.js | native |
-| ------ | --- | -------- | ------ |
-| core   | ✅   | ✅        | ✅      |
-| http4s | ✅   | ✅        | ✅      |
-| slf4j  | ✅   | 🚫        | 🚫      |
+| Module  | JVM   | scala.js  | native |
+|---------|-------|-----------|--------|
+| core    | ✅    | ✅        | ✅     |
+| http4s  | ✅    | ✅        | ✅     |
+| slf4j   | ✅    | 🚫        | 🚫     |
+| slf4j-2 | ✅    | 🚫        | 🚫     |
 
 ## Installation
 
@@ -98,10 +99,10 @@ and running it yields:
 ```scala
 import cats.effect.unsafe.implicits.global
 main.unsafeRunSync()
-// 2022-11-15 08:35:04 [DEBUG] repl.MdocSession$.MdocApp: This is some debug (README.md:27)
-// 2022-11-15 08:35:04 [INFO ] repl.MdocSession$.MdocApp: HEY! (README.md:28)
-// 2022-11-15 08:35:04 [WARN ] repl.MdocSession$.MdocApp: I'm warning you (README.md:29)
-// 2022-11-15 08:35:04 [ERROR] repl.MdocSession$.MdocApp: I give up (README.md:30)
+// 2023-03-07 08:45:23 [DEBUG] repl.MdocSession$.MdocApp: This is some debug (README.md:27)
+// 2023-03-07 08:45:23 [INFO ] repl.MdocSession$.MdocApp: HEY! (README.md:28)
+// 2023-03-07 08:45:23 [WARN ] repl.MdocSession$.MdocApp: I'm warning you (README.md:29)
+// 2023-03-07 08:45:23 [ERROR] repl.MdocSession$.MdocApp: I give up (README.md:30)
 ```
 
 We can also re-use the program and add context to our logger:
@@ -120,11 +121,11 @@ And running with context yields:
 
 ```scala
 mainWithContext.unsafeRunSync()
-// 2022-11-15 08:35:04 [DEBUG] trace-id=4d334544-6462-43fa-b0b1-12846f871573 repl.MdocSession$.MdocApp: This is some debug (README.md:27)
-// 2022-11-15 08:35:04 [INFO ] trace-id=4d334544-6462-43fa-b0b1-12846f871573 repl.MdocSession$.MdocApp: HEY! (README.md:28)
-// 2022-11-15 08:35:04 [WARN ] trace-id=4d334544-6462-43fa-b0b1-12846f871573 repl.MdocSession$.MdocApp: I'm warning you (README.md:29)
-// 2022-11-15 08:35:04 [ERROR] trace-id=4d334544-6462-43fa-b0b1-12846f871573 repl.MdocSession$.MdocApp: I give up (README.md:30)
-// 2022-11-15 08:35:04 [INFO ] repl.MdocSession$.MdocApp: Now the context is gone (README.md:61)
+// 2023-03-07 08:45:23 [DEBUG] trace-id=4d334544-6462-43fa-b0b1-12846f871573 repl.MdocSession$.MdocApp: This is some debug (README.md:27)
+// 2023-03-07 08:45:23 [INFO ] trace-id=4d334544-6462-43fa-b0b1-12846f871573 repl.MdocSession$.MdocApp: HEY! (README.md:28)
+// 2023-03-07 08:45:23 [WARN ] trace-id=4d334544-6462-43fa-b0b1-12846f871573 repl.MdocSession$.MdocApp: I'm warning you (README.md:29)
+// 2023-03-07 08:45:23 [ERROR] trace-id=4d334544-6462-43fa-b0b1-12846f871573 repl.MdocSession$.MdocApp: I give up (README.md:30)
+// 2023-03-07 08:45:23 [INFO ] repl.MdocSession$.MdocApp: Now the context is gone (README.md:61)
 ```
 
 ## Can I use `SLF4J`?
@@ -156,12 +157,15 @@ To use this program with woof
 
 ```scala
 import org.legogroup.woof.slf4j.*
+import cats.effect.std.Dispatcher
 val mainSlf4j: IO[Unit] = 
-  for
-    woofLogger  <- DefaultLogger.makeIo(consoleOutput)
-    _           <- woofLogger.registerSlf4j
-    _           <- programWithSlf4j
-  yield ()
+  Dispatcher.sequential[IO].use( implicit dispatcher =>
+    for
+      woofLogger  <- DefaultLogger.makeIo(consoleOutput)
+      _           <- woofLogger.registerSlf4j
+      _           <- programWithSlf4j
+    yield ()
+  )
 ```
 
 and running it:
@@ -219,8 +223,8 @@ the correlation ID is also returned in the header of the response.
 
 ```scala
 mainHttp4s.unsafeRunSync()
-// 2022-11-15 08:35:04 [INFO ] X-Trace-Id=db188825-ab1f-4e47-92d9-cdbe05b12209 repl.MdocSession$.MdocApp: I got a request with trace id! :D (README.md:121)
-// 2022-11-15 08:35:04 [INFO ] repl.MdocSession$.MdocApp: Got response headers: Headers(X-Trace-Id: db188825-ab1f-4e47-92d9-cdbe05b12209) (README.md:142)
+// 2023-03-07 08:45:24 [INFO ] X-Trace-Id=aba486cd-d6bc-4f1a-b64e-15eed546bca3 repl.MdocSession$.MdocApp: I got a request with trace id! :D (README.md:126)
+// 2023-03-07 08:45:24 [INFO ] repl.MdocSession$.MdocApp: Got response headers: Headers(X-Trace-Id: aba486cd-d6bc-4f1a-b64e-15eed546bca3) (README.md:147)
 ```
 
 ## Structured Logging
@@ -245,11 +249,11 @@ And running with context yields:
 
 ```scala
 contextAsJson.unsafeRunSync()
-// {"level":"Debug","epochMillis":1668497704365,"timeStamp":"2022-11-15T07:35:04Z","enclosingClass":"repl.MdocSession$.MdocApp","lineNumber":26,"message":"This is some debug","context":{"bar":"1337","foo":"42"}}
-// {"level":"Info","epochMillis":1668497704366,"timeStamp":"2022-11-15T07:35:04Z","enclosingClass":"repl.MdocSession$.MdocApp","lineNumber":27,"message":"HEY!","context":{"bar":"1337","foo":"42"}}
-// {"level":"Warn","epochMillis":1668497704366,"timeStamp":"2022-11-15T07:35:04Z","enclosingClass":"repl.MdocSession$.MdocApp","lineNumber":28,"message":"I'm warning you","context":{"bar":"1337","foo":"42"}}
-// {"level":"Error","epochMillis":1668497704366,"timeStamp":"2022-11-15T07:35:04Z","enclosingClass":"repl.MdocSession$.MdocApp","lineNumber":29,"message":"I give up","context":{"bar":"1337","foo":"42"}}
-// {"level":"Info","epochMillis":1668497704367,"timeStamp":"2022-11-15T07:35:04Z","enclosingClass":"repl.MdocSession$.MdocApp","lineNumber":163,"message":"Now the context is gone","context":{}}
+// {"level":"Debug","epochMillis":1678175124381,"timeStamp":"2023-03-07T07:45:24Z","enclosingClass":"repl.MdocSession$.MdocApp","lineNumber":26,"message":"This is some debug","context":{"bar":"1337","foo":"42"}}
+// {"level":"Info","epochMillis":1678175124383,"timeStamp":"2023-03-07T07:45:24Z","enclosingClass":"repl.MdocSession$.MdocApp","lineNumber":27,"message":"HEY!","context":{"bar":"1337","foo":"42"}}
+// {"level":"Warn","epochMillis":1678175124383,"timeStamp":"2023-03-07T07:45:24Z","enclosingClass":"repl.MdocSession$.MdocApp","lineNumber":28,"message":"I'm warning you","context":{"bar":"1337","foo":"42"}}
+// {"level":"Error","epochMillis":1678175124383,"timeStamp":"2023-03-07T07:45:24Z","enclosingClass":"repl.MdocSession$.MdocApp","lineNumber":29,"message":"I give up","context":{"bar":"1337","foo":"42"}}
+// {"level":"Info","epochMillis":1678175124383,"timeStamp":"2023-03-07T07:45:24Z","enclosingClass":"repl.MdocSession$.MdocApp","lineNumber":168,"message":"Now the context is gone","context":{}}
 ```
 
 > We are considering if we should support matching different printers with different outputs: Maybe you want human readable logs for standard out and structured logging for your monitoring tools. However, this will be a breaking change.
diff --git a/build.sbt b/build.sbt
@@ -9,11 +9,13 @@ val V = new {
   val munitCatsEffect = "2.0.0-M3"
   val scala           = "3.2.2"
   val slf4j           = "1.7.36"
+  val slf4j2          = "2.0.6"
   val tzdb            = "2.5.0"
 }
 
 val D = new {
-  val slf4jApi = "org.slf4j" % "slf4j-api" % V.slf4j
+  val slf4jApi  = "org.slf4j" % "slf4j-api" % V.slf4j
+  val slf4jApi2 = "org.slf4j" % "slf4j-api" % V.slf4j2
 
   val catsCore          = Def.setting("org.typelevel" %%% "cats-core" % V.cats)
   val catsEffect        = Def.setting("org.typelevel" %%% "cats-effect" % V.catsEffect)
@@ -79,7 +81,8 @@ lazy val root =
       List(
         core,
         http4s,
-        slf4j
+        slf4j,
+        slf4j2
       ).flatMap(_.componentProjects).map(_.project): _*
     )
     .settings(
@@ -117,7 +120,15 @@ lazy val http4s = crossProject(JSPlatform, JVMPlatform, NativePlatform)
 
 lazy val slf4j = woofProject(file("./modules/slf4j"))
   .settings(libraryDependencies += D.slf4jApi)
-  .dependsOn(core.jvm % "compile->compile;test->test")
+  .dependsOn(slf4jCommon % "compile->compile;test->test")
+
+lazy val slf4j2 = woofProject(file("./modules/slf4j-2"))
+  .settings(libraryDependencies += D.slf4jApi2)
+  .dependsOn(slf4jCommon % "compile->compile;test->test")
+
+lazy val slf4jCommon =
+  woofProject(file("./modules/slf4j-common"))
+    .dependsOn(core.jvm % "compile->compile;test->test")
 
 lazy val examples = project
   .in(file("./modules/examples"))

diff --git a/docs/README.md b/docs/README.md
@@ -26,11 +26,12 @@ A **pure** _(in both senses of the word!)_ **Scala 3** logging library with **no
 
 ### Cross platform
 
-| Module | JVM | scala.js | native |
-| ------ | --- | -------- | ------ |
-| core   | ✅   | ✅        | ✅      |
-| http4s | ✅   | ✅        | ✅      |
-| slf4j  | ✅   | 🚫        | 🚫      |
+| Module  | JVM   | scala.js  | native |
+|---------|-------|-----------|--------|
+| core    | ✅    | ✅        | ✅     |
+| http4s  | ✅    | ✅        | ✅     |
+| slf4j   | ✅    | 🚫        | 🚫     |
+| slf4j-2 | ✅    | 🚫        | 🚫     |
 
 ## Installation
 
@@ -147,12 +148,15 @@ To use this program with woof
 
 ```scala mdoc:silent
 import org.legogroup.woof.slf4j.*
+import cats.effect.std.Dispatcher
 val mainSlf4j: IO[Unit] = 
-  for
-    woofLogger  <- DefaultLogger.makeIo(consoleOutput)
-    _           <- woofLogger.registerSlf4j
-    _           <- programWithSlf4j
-  yield ()
+  Dispatcher.sequential[IO].use( implicit dispatcher =>
+    for
+      woofLogger  <- DefaultLogger.makeIo(consoleOutput)
+      _           <- woofLogger.registerSlf4j
+      _           <- programWithSlf4j
+    yield ()
+  )
 ```
 
 and running it:

diff --git a/modules/slf4j-2/src/main/resources/META-INF/services/org.slf4j.spi.SLF4JServiceProvider b/modules/slf4j-2/src/main/resources/META-INF/services/org.slf4j.spi.SLF4JServiceProvider
@@ -0,0 +1 @@
+org.legogroup.woof.slf4j2.WoofLoggerServiceProvider
diff --git a/modules/slf4j-2/src/main/scala/org/legogroup/woof/slf4j2/WoofLogger.scala b/modules/slf4j-2/src/main/scala/org/legogroup/woof/slf4j2/WoofLogger.scala
@@ -0,0 +1,29 @@
+package org.legogroup.woof.slf4j2
+
+import cats.Id
+import cats.effect.IO
+import cats.effect.std.Dispatcher
+import cats.effect.unsafe.IORuntime
+import cats.effect.unsafe.IORuntime.global
+import org.legogroup.woof.slf4j.Slf4jWoofLoggerImpl
+import org.legogroup.woof.{EnclosingClass, LogInfo, LogLevel, LogLine, Logger as WLogger}
+import org.slf4j.{Logger, Marker}
+
+import java.io.File
+import scala.util.Try
+
+class WoofLogger(name: String) extends Logger with Slf4jWoofLoggerImpl[IO, Marker](name):
+  override def logger: Option[WLogger[IO]]        = WoofLogger.logger
+  override def dispatcher: Option[Dispatcher[IO]] = WoofLogger.dispatcher
+end WoofLogger
+
+object WoofLogger:
+  var logger: Option[WLogger[IO]]        = None
+  var dispatcher: Option[Dispatcher[IO]] = None
+end WoofLogger
+
+extension (w: WLogger[IO])
+  def registerSlf4j(using d: Dispatcher[IO]): IO[Unit] = IO.delay {
+    WoofLogger.logger = Some(w)
+    WoofLogger.dispatcher = Some(d)
+  }
diff --git a/modules/slf4j-2/src/main/scala/org/legogroup/woof/slf4j2/WoofLoggerServiceProvider.scala b/modules/slf4j-2/src/main/scala/org/legogroup/woof/slf4j2/WoofLoggerServiceProvider.scala
@@ -0,0 +1,8 @@
+package org.legogroup.woof.slf4j2
+
+import org.slf4j.ILoggerFactory
+import org.slf4j.helpers.NOP_FallbackServiceProvider
+
+class WoofLoggerServiceProvider extends NOP_FallbackServiceProvider:
+  override def getLoggerFactory: ILoggerFactory = (name: String) => new WoofLogger(name)
+end WoofLoggerServiceProvider
diff --git a/modules/slf4j-2/src/test/resources/META-INF/services/org.slf4j.spi.SLF4JServiceProvider b/modules/slf4j-2/src/test/resources/META-INF/services/org.slf4j.spi.SLF4JServiceProvider
@@ -0,0 +1 @@
+org.legogroup.woof.slf4j2.WoofLoggerServiceProvider
diff --git a/modules/slf4j-2/src/test/scala/org/legogroup/woof/slf4j2/Slf4j2Suite.scala b/modules/slf4j-2/src/test/scala/org/legogroup/woof/slf4j2/Slf4j2Suite.scala
@@ -0,0 +1,107 @@
+package org.legogroup.woof.slf4j2
+
+import cats.Id
+import cats.effect.IO
+import cats.effect.kernel.Clock
+import cats.effect.std.Dispatcher
+import org.legogroup.woof.*
+import org.slf4j.LoggerFactory
+
+import scala.concurrent.duration.*
+
+class Slf4j2Suite extends munit.CatsEffectSuite:
+
+  override def munitIOTimeout = 10.minutes
+
+
+  val dispatcher = ResourceFunFixture(Dispatcher.sequential[IO](true))
+
+  dispatcher.test("should log stuff") { implicit dispatcher =>
+    given Printer = NoColorPrinter(testFormatTime)
+
+    given Filter = Filter.everything
+
+    given Clock[IO] = leetClock
+
+    for
+      stringOutput <- newStringWriter
+      woofLogger <- DefaultLogger.makeIo(stringOutput)
+      _ <- woofLogger.registerSlf4j
+      slf4jLogger <- IO.delay(LoggerFactory.getLogger(this.getClass))
+      _ <- IO.delay(slf4jLogger.info("HELLO, SLF4J!"))
+      result <- stringOutput.get
+    yield assertEquals(
+      result,
+      "1987-05-31 13:37:00 [INFO ] org.legogroup.woof.slf4j2.Slf4j2Suite: HELLO, SLF4J! (Slf4j2Suite.scala:31)\n",
+    )
+    end for
+  }
+
+  dispatcher.test("should log arrays of objects") { implicit dispatcher =>
+    given Printer = NoColorPrinter(testFormatTime)
+
+    given Filter = Filter.everything
+
+    given Clock[IO] = leetClock
+
+    for
+      stringOutput <- newStringWriter
+      woofLogger <- DefaultLogger.makeIo(stringOutput)
+      _ <- woofLogger.registerSlf4j
+      slf4jLogger <- IO.delay(LoggerFactory.getLogger(this.getClass))
+      _ <- IO.delay(slf4jLogger.info("HELLO, ARRAYS!", 1, Some(42), List(1337)))
+      result <- stringOutput.get
+    yield assertEquals(
+      result,
+      "1987-05-31 13:37:00 [INFO ] org.legogroup.woof.slf4j2.Slf4j2Suite: HELLO, ARRAYS! 1, Some(42), List(1337) (Slf4j2Suite.scala:52)\n",
+    )
+    end for
+  }
+
+  dispatcher.test("should respect log levels") { implicit dispatcher =>
+    given Printer = NoColorPrinter(testFormatTime)
+
+    given Filter = Filter.exactLevel(LogLevel.Warn)
+
+    given Clock[IO] = leetClock
+
+    for
+      stringWriter <- newStringWriter
+      woofLogger <- DefaultLogger.makeIo(stringWriter)
+      _ <- woofLogger.registerSlf4j
+      slf4jLogger <- IO.delay(LoggerFactory.getLogger(this.getClass))
+      _ <- IO.delay(slf4jLogger.info("INFO, SLF4J!"))
+      _ <- IO.delay(slf4jLogger.debug("DEBUG, SLF4J!"))
+      _ <- IO.delay(slf4jLogger.warn("WARN, SLF4J!"))
+      _ <- IO.delay(slf4jLogger.error("ERROR, SLF4J!"))
+      result <- stringWriter.get
+    yield assertEquals(
+      result,
+      "1987-05-31 13:37:00 [WARN ] org.legogroup.woof.slf4j2.Slf4j2Suite: WARN, SLF4J! (Slf4j2Suite.scala:75)\n",
+    )
+    end for
+  }
+
+  dispatcher.test("should not fail on null throwable") { implicit dispatcher =>
+    given Printer = NoColorPrinter(testFormatTime)
+
+    given Filter = Filter.everything
+
+    given Clock[IO] = leetClock
+
+    for
+      stringWriter <- newStringWriter
+      woofLogger <- DefaultLogger.makeIo(stringWriter)
+      _ <- woofLogger.registerSlf4j
+      slf4jLogger <- IO.delay(LoggerFactory.getLogger(this.getClass))
+      _ <- IO.delay(slf4jLogger.debug("null exception", null))
+      result <- stringWriter.get
+    yield assertEquals(
+      result,
+      "1987-05-31 13:37:00 [DEBUG] org.legogroup.woof.slf4j2.Slf4j2Suite: null exception  (Slf4j2Suite.scala:97)\n",
+    )
+    end for
+  }
+
+
+end Slf4j2Suite
diff --git a/modules/slf4j-common/src/main/scala/org/legogroup/woof/slf4j/Slf4jWoofLoggerImpl.scala b/modules/slf4j-common/src/main/scala/org/legogroup/woof/slf4j/Slf4jWoofLoggerImpl.scala
@@ -0,0 +1,108 @@
+package org.legogroup.woof.slf4j
+
+import cats.Functor
+import cats.effect.std.Dispatcher
+import org.legogroup.woof.*
+import cats.syntax.all.*
+
+import scala.util.Try
+
+trait Slf4jWoofLoggerImpl[F[_], Marker](name: String):
+
+  private def getLogInfo() =
+    val stacktraceElements = Thread.currentThread().getStackTrace()
+    val lastIndex = stacktraceElements.reverse.indexWhere(s =>
+      s.getClassName == this.getClass.getName
+    ) // after last mention of this class
+    val callingMethodIndex               = stacktraceElements.size - lastIndex
+    val callingMethod: StackTraceElement = stacktraceElements(callingMethodIndex)
+    val enclosingClassName               = EnclosingClass(callingMethod.getClassName)
+    val fileName   = (enclosingClassName.fullName.replace('.', '/') + ".scala").split("\\/").takeRight(1).mkString
+    val lineNumber = callingMethod.getLineNumber - 1
+    LogInfo(enclosingClassName, fileName, lineNumber)
+  end getLogInfo
+
+  def getName(): String = name
+
+  def logger: Option[Logger[F]]
+  def dispatcher: Option[Dispatcher[F]]
+
+  private def log(level: LogLevel, msg: String): Unit =
+    (logger, dispatcher).mapN { (l, dispatcher) =>
+      val logInfo = getLogInfo()
+      val _       = dispatcher.unsafeRunSync(l.doLog(level, msg)(using logInfo))
+    }
+
+  def info(msg: String): Unit  = log(LogLevel.Info, msg)
+  def debug(msg: String): Unit = log(LogLevel.Debug, msg)
+  def error(msg: String): Unit = log(LogLevel.Error, msg)
+  def trace(msg: String): Unit = log(LogLevel.Trace, msg)
+  def warn(msg: String): Unit  = log(LogLevel.Warn, msg)
+
+  private def throwableMessage(msg: String, throwable: Throwable) = s"$msg " + Try(throwable.getMessage).getOrElse("")
+
+  def debug(msg: String, obj: Object): Unit                             = debug(s"$msg $obj")
+  def debug(msg: String, obj1: Object, obj2: Object): Unit              = debug(s"$msg $obj1, $obj2")
+  def debug(msg: String, objs: Array[? <: Object]): Unit                = debug(s"$msg ${objs.mkString(", ")}")
+  def debug(msg: String, throwable: Throwable): Unit                    = debug(throwableMessage(msg, throwable))
+  def debug(x$0: Marker, msg: String): Unit                             = debug(msg)
+  def debug(x$0: Marker, msg: String, obj: Object): Unit                = debug(s"$msg, $obj")
+  def debug(x$0: Marker, msg: String, obj1: Object, obj2: Object): Unit = debug(s"$msg, $obj1, $obj2")
+  def debug(x$0: Marker, msg: String, objs: Array[? <: Object]): Unit   = debug(s"$msg ${objs.mkString(", ")}")
+  def debug(x$0: Marker, msg: String, throwable: Throwable): Unit       = debug(throwableMessage(msg, throwable))
+
+  def error(msg: String, obj: Object): Unit                             = error(s"$msg $obj")
+  def error(msg: String, obj1: Object, obj2: Object): Unit              = error(s"$msg $obj1, $obj2")
+  def error(msg: String, objs: Array[? <: Object]): Unit                = error(s"$msg ${objs.mkString(", ")}")
+  def error(msg: String, throwable: Throwable): Unit                    = error(throwableMessage(msg, throwable))
+  def error(x$0: Marker, msg: String): Unit                             = error(msg)
+  def error(x$0: Marker, msg: String, obj: Object): Unit                = error(s"$msg $obj")
+  def error(x$0: Marker, msg: String, obj1: Object, obj2: Object): Unit = error(s"$msg $obj1, $obj2")
+  def error(x$0: Marker, msg: String, objs: Array[? <: Object]): Unit   = error(s"$msg ${objs.mkString(", ")}")
+  def error(x$0: Marker, msg: String, throwable: Throwable): Unit       = error(throwableMessage(msg, throwable))
+
+  def info(msg: String, obj: Object): Unit                             = info(s"$msg, $obj")
+  def info(msg: String, obj1: Object, obj2: Object): Unit              = info(s"$msg, $obj1, $obj2")
+  def info(msg: String, objs: Array[? <: Object]): Unit                = info(s"$msg ${objs.mkString(", ")}")
+  def info(msg: String, throwable: Throwable): Unit                    = info(throwableMessage(msg, throwable))
+  def info(x$0: Marker, msg: String): Unit                             = info(msg)
+  def info(x$0: Marker, msg: String, obj: Object): Unit                = info(s"$msg, $obj")
+  def info(x$0: Marker, msg: String, obj1: Object, obj2: Object): Unit = info(s"$msg, $obj1, $obj2")
+  def info(x$0: Marker, msg: String, objs: Array[? <: Object]): Unit   = info(s"$msg ${objs.mkString(", ")}")
+  def info(x$0: Marker, msg: String, throwable: Throwable): Unit       = info(throwableMessage(msg, throwable))
+
+  def trace(msg: String, obj: Object): Unit                             = trace(s"$msg, $obj")
+  def trace(msg: String, obj1: Object, obj2: Object): Unit              = trace(s"$msg, $obj1, $obj2")
+  def trace(msg: String, objs: Array[? <: Object]): Unit                = trace(s"$msg ${objs.mkString(", ")}")
+  def trace(msg: String, throwable: Throwable): Unit                    = trace(throwableMessage(msg, throwable))
+  def trace(x$0: Marker, msg: String): Unit                             = trace(msg)
+  def trace(x$0: Marker, msg: String, obj: Object): Unit                = trace(s"$msg, $obj")
+  def trace(x$0: Marker, msg: String, obj1: Object, obj2: Object): Unit = trace(s"$msg, $obj1, $obj2")
+  def trace(x$0: Marker, msg: String, objs: Array[? <: Object]): Unit   = trace(s"$msg ${objs.mkString(", ")}")
+  def trace(x$0: Marker, msg: String, throwable: Throwable): Unit       = trace(throwableMessage(msg, throwable))
+
+  def warn(msg: String, obj: Object): Unit                             = warn(s"$msg, $obj")
+  def warn(msg: String, obj1: Object, obj2: Object): Unit              = warn(s"$msg, $obj1, $obj2")
+  def warn(msg: String, objs: Array[? <: Object]): Unit                = warn(s"$msg ${objs.mkString(", ")}")
+  def warn(msg: String, throwable: Throwable): Unit                    = warn(throwableMessage(msg, throwable))
+  def warn(x$0: Marker, msg: String): Unit                             = warn(msg)
+  def warn(x$0: Marker, msg: String, obj: Object): Unit                = warn(s"$msg, $obj")
+  def warn(x$0: Marker, msg: String, obj1: Object, obj2: Object): Unit = warn(s"$msg, $obj1, $obj2")
+  def warn(x$0: Marker, msg: String, objs: Array[? <: Object]): Unit   = warn(s"$msg ${objs.mkString(", ")}")
+  def warn(x$0: Marker, msg: String, throwable: Throwable): Unit       = warn(throwableMessage(msg, throwable))
+
+  private def testLevel(logLevel: LogLevel): Boolean = true
+
+  def isDebugEnabled(): Boolean = testLevel(LogLevel.Debug)
+  def isErrorEnabled(): Boolean = testLevel(LogLevel.Error)
+  def isInfoEnabled(): Boolean  = testLevel(LogLevel.Info)
+  def isTraceEnabled(): Boolean = testLevel(LogLevel.Trace)
+  def isWarnEnabled(): Boolean  = testLevel(LogLevel.Warn)
+
+  def isInfoEnabled(x$0: Marker): Boolean  = isInfoEnabled()
+  def isTraceEnabled(x$0: Marker): Boolean = isTraceEnabled()
+  def isDebugEnabled(x$0: Marker): Boolean = isDebugEnabled()
+  def isErrorEnabled(x$0: Marker): Boolean = isErrorEnabled()
+  def isWarnEnabled(x$0: Marker): Boolean  = isWarnEnabled()
+
+end Slf4jWoofLoggerImpl
diff --git a/modules/slf4j/src/main/scala/org/legogroup/woof/slf4j/WoofLogger.scala b/modules/slf4j/src/main/scala/org/legogroup/woof/slf4j/WoofLogger.scala
@@ -2,111 +2,27 @@ package org.legogroup.woof.slf4j
 
 import cats.Id
 import cats.effect.IO
+import cats.effect.std.Dispatcher
 import cats.effect.unsafe.IORuntime
 import cats.effect.unsafe.IORuntime.global
 import org.legogroup.woof.{EnclosingClass, LogInfo, LogLevel, LogLine, Logger as WLogger}
-import org.slf4j.Logger
+import org.slf4j.{Logger, Marker}
 
 import java.io.File
 import scala.util.Try
-class WoofLogger(name: String) extends Logger:
-
-  import WoofLogger.{given_IORuntime, logger}
-
-  private def getLogInfo() =
-    val stacktraceElements = Thread.currentThread().getStackTrace()
-    val lastIndex = stacktraceElements.reverse.indexWhere(s =>
-      s.getClassName == this.getClass.getName
-    ) // after last mention of this class
-    val callingMethodIndex               = stacktraceElements.size - lastIndex
-    val callingMethod: StackTraceElement = stacktraceElements(callingMethodIndex)
-    val enclosingClassName               = EnclosingClass(callingMethod.getClassName)
-    val fileName   = (enclosingClassName.fullName.replace('.', '/') + ".scala").split("\\/").takeRight(1).mkString
-    val lineNumber = callingMethod.getLineNumber - 1
-    LogInfo(enclosingClassName, fileName, lineNumber)
-  end getLogInfo
-
-  def getName(): String = name
-
-  private def log(level: LogLevel, msg: String) =
-    logger.foreach(_.doLog(level, msg)(using getLogInfo()).unsafeRunSync())
-  def info(msg: String): Unit  = log(LogLevel.Info, msg)
-  def debug(msg: String): Unit = log(LogLevel.Debug, msg)
-  def error(msg: String): Unit = log(LogLevel.Error, msg)
-  def trace(msg: String): Unit = log(LogLevel.Trace, msg)
-  def warn(msg: String): Unit  = log(LogLevel.Warn, msg)
-
-  private def throwableMessage(msg: String, throwable: Throwable) = s"$msg " + Try(throwable.getMessage).getOrElse("")
-
-  def debug(msg: String, obj: Object): Unit                        = debug(s"$msg $obj")
-  def debug(msg: String, obj1: Object, obj2: Object): Unit         = debug(s"$msg $obj1, $obj2")
-  def debug(msg: String, objs: Array[? <: Object]): Unit           = debug(s"$msg ${objs.mkString(", ")}")
-  def debug(msg: String, throwable: Throwable): Unit               = debug(throwableMessage(msg, throwable))
-  def debug(x$0: org.slf4j.Marker, msg: String): Unit              = debug(msg)
-  def debug(x$0: org.slf4j.Marker, msg: String, obj: Object): Unit = debug(s"$msg, $obj")
-  def debug(x$0: org.slf4j.Marker, msg: String, obj1: Object, obj2: Object): Unit = debug(s"$msg, $obj1, $obj2")
-  def debug(x$0: org.slf4j.Marker, msg: String, objs: Array[? <: Object]): Unit = debug(s"$msg ${objs.mkString(", ")}")
-  def debug(x$0: org.slf4j.Marker, msg: String, throwable: Throwable): Unit = debug(throwableMessage(msg, throwable))
-
-  def error(msg: String, obj: Object): Unit                        = error(s"$msg $obj")
-  def error(msg: String, obj1: Object, obj2: Object): Unit         = error(s"$msg $obj1, $obj2")
-  def error(msg: String, objs: Array[? <: Object]): Unit           = error(s"$msg ${objs.mkString(", ")}")
-  def error(msg: String, throwable: Throwable): Unit               = error(throwableMessage(msg, throwable))
-  def error(x$0: org.slf4j.Marker, msg: String): Unit              = error(msg)
-  def error(x$0: org.slf4j.Marker, msg: String, obj: Object): Unit = error(s"$msg $obj")
-  def error(x$0: org.slf4j.Marker, msg: String, obj1: Object, obj2: Object): Unit = error(s"$msg $obj1, $obj2")
-  def error(x$0: org.slf4j.Marker, msg: String, objs: Array[? <: Object]): Unit = error(s"$msg ${objs.mkString(", ")}")
-  def error(x$0: org.slf4j.Marker, msg: String, throwable: Throwable): Unit = error(throwableMessage(msg, throwable))
-
-  def info(msg: String, obj: Object): Unit                        = info(s"$msg, $obj")
-  def info(msg: String, obj1: Object, obj2: Object): Unit         = info(s"$msg, $obj1, $obj2")
-  def info(msg: String, objs: Array[? <: Object]): Unit           = info(s"$msg ${objs.mkString(", ")}")
-  def info(msg: String, throwable: Throwable): Unit               = info(throwableMessage(msg, throwable))
-  def info(x$0: org.slf4j.Marker, msg: String): Unit              = info(msg)
-  def info(x$0: org.slf4j.Marker, msg: String, obj: Object): Unit = info(s"$msg, $obj")
-  def info(x$0: org.slf4j.Marker, msg: String, obj1: Object, obj2: Object): Unit = info(s"$msg, $obj1, $obj2")
-  def info(x$0: org.slf4j.Marker, msg: String, objs: Array[? <: Object]): Unit   = info(s"$msg ${objs.mkString(", ")}")
-  def info(x$0: org.slf4j.Marker, msg: String, throwable: Throwable): Unit = info(throwableMessage(msg, throwable))
-
-  def trace(msg: String, obj: Object): Unit                        = trace(s"$msg, $obj")
-  def trace(msg: String, obj1: Object, obj2: Object): Unit         = trace(s"$msg, $obj1, $obj2")
-  def trace(msg: String, objs: Array[? <: Object]): Unit           = trace(s"$msg ${objs.mkString(", ")}")
-  def trace(msg: String, throwable: Throwable): Unit               = trace(throwableMessage(msg, throwable))
-  def trace(x$0: org.slf4j.Marker, msg: String): Unit              = trace(msg)
-  def trace(x$0: org.slf4j.Marker, msg: String, obj: Object): Unit = trace(s"$msg, $obj")
-  def trace(x$0: org.slf4j.Marker, msg: String, obj1: Object, obj2: Object): Unit = trace(s"$msg, $obj1, $obj2")
-  def trace(x$0: org.slf4j.Marker, msg: String, objs: Array[? <: Object]): Unit = trace(s"$msg ${objs.mkString(", ")}")
-  def trace(x$0: org.slf4j.Marker, msg: String, throwable: Throwable): Unit = trace(throwableMessage(msg, throwable))
-
-  def warn(msg: String, obj: Object): Unit                        = warn(s"$msg, $obj")
-  def warn(msg: String, obj1: Object, obj2: Object): Unit         = warn(s"$msg, $obj1, $obj2")
-  def warn(msg: String, objs: Array[? <: Object]): Unit           = warn(s"$msg ${objs.mkString(", ")}")
-  def warn(msg: String, throwable: Throwable): Unit               = warn(throwableMessage(msg, throwable))
-  def warn(x$0: org.slf4j.Marker, msg: String): Unit              = warn(msg)
-  def warn(x$0: org.slf4j.Marker, msg: String, obj: Object): Unit = warn(s"$msg, $obj")
-  def warn(x$0: org.slf4j.Marker, msg: String, obj1: Object, obj2: Object): Unit = warn(s"$msg, $obj1, $obj2")
-  def warn(x$0: org.slf4j.Marker, msg: String, objs: Array[? <: Object]): Unit   = warn(s"$msg ${objs.mkString(", ")}")
-  def warn(x$0: org.slf4j.Marker, msg: String, throwable: Throwable): Unit = warn(throwableMessage(msg, throwable))
-
-  private def testLevel(logLevel: LogLevel): Boolean = true
-
-  def isDebugEnabled(): Boolean = testLevel(LogLevel.Debug)
-  def isErrorEnabled(): Boolean = testLevel(LogLevel.Error)
-  def isInfoEnabled(): Boolean  = testLevel(LogLevel.Info)
-  def isTraceEnabled(): Boolean = testLevel(LogLevel.Trace)
-  def isWarnEnabled(): Boolean  = testLevel(LogLevel.Warn)
-
-  def isInfoEnabled(x$0: org.slf4j.Marker): Boolean  = isInfoEnabled()
-  def isTraceEnabled(x$0: org.slf4j.Marker): Boolean = isTraceEnabled()
-  def isDebugEnabled(x$0: org.slf4j.Marker): Boolean = isDebugEnabled()
-  def isErrorEnabled(x$0: org.slf4j.Marker): Boolean = isErrorEnabled()
-  def isWarnEnabled(x$0: org.slf4j.Marker): Boolean  = isWarnEnabled()
 
+class WoofLogger(name: String) extends Logger with Slf4jWoofLoggerImpl[IO, Marker](name):
+  override def logger: Option[WLogger[IO]]        = WoofLogger.logger
+  override def dispatcher: Option[Dispatcher[IO]] = WoofLogger.dispatcher
 end WoofLogger
 
 object WoofLogger:
-  private given IORuntime         = global
-  var logger: Option[WLogger[IO]] = None
+  var logger: Option[WLogger[IO]]        = None
+  var dispatcher: Option[Dispatcher[IO]] = None
 end WoofLogger
 
-extension (w: WLogger[IO]) def registerSlf4j: IO[Unit] = IO.delay(WoofLogger.logger = Some(w))
+extension (w: WLogger[IO])
+  def registerSlf4j(using d: Dispatcher[IO]): IO[Unit] = IO.delay {
+    WoofLogger.logger = Some(w)
+    WoofLogger.dispatcher = Some(d)
+  }
diff --git a/modules/slf4j/src/main/scala/org/slf4j/impl/StaticLoggerBinder.scala b/modules/slf4j/src/main/scala/org/slf4j/impl/StaticLoggerBinder.scala
@@ -1,5 +1,7 @@
 package org.slf4j.impl
 
+import cats.effect.IO
+import cats.effect.std.Dispatcher
 import org.legogroup.woof.slf4j.WoofLogger
 import org.slf4j.spi.LoggerFactoryBinder
 import org.slf4j.{ILoggerFactory, Logger, LoggerFactory}

diff --git a/modules/slf4j/src/test/scala/org/legogroup/woof/slf4j/Slf4jSuite.scala b/modules/slf4j/src/test/scala/org/legogroup/woof/slf4j/Slf4jSuite.scala
@@ -3,6 +3,7 @@ package org.legogroup.woof.slf4j
 import cats.Id
 import cats.effect.IO
 import cats.effect.kernel.Clock
+import cats.effect.std.Dispatcher
 import org.legogroup.woof.*
 import org.slf4j.LoggerFactory
 import org.slf4j.impl.StaticLoggerBinder
@@ -13,7 +14,9 @@ class Slf4jSuite extends munit.CatsEffectSuite:
 
   override def munitIOTimeout = 10.minutes
 
-  test("should log stuff") {
+  val dispatcher = ResourceFunFixture(Dispatcher.sequential[IO](true))
+
+  dispatcher.test("should log stuff") { implicit dispatcher =>
     given Printer   = NoColorPrinter(testFormatTime)
     given Filter    = Filter.everything
     given Clock[IO] = leetClock
@@ -26,12 +29,12 @@ class Slf4jSuite extends munit.CatsEffectSuite:
       result       <- stringOutput.get
     yield assertEquals(
       result,
-      "1987-05-31 13:37:00 [INFO ] org.legogroup.woof.slf4j.Slf4jSuite: HELLO, SLF4J! (Slf4jSuite.scala:25)\n",
+      "1987-05-31 13:37:00 [INFO ] org.legogroup.woof.slf4j.Slf4jSuite: HELLO, SLF4J! (Slf4jSuite.scala:28)\n",
     )
     end for
   }
 
-  test("should log arrays of objects") {
+  dispatcher.test("should log arrays of objects") { implicit dispatcher =>
     given Printer   = NoColorPrinter(testFormatTime)
     given Filter    = Filter.everything
     given Clock[IO] = leetClock
@@ -44,12 +47,12 @@ class Slf4jSuite extends munit.CatsEffectSuite:
       result       <- stringOutput.get
     yield assertEquals(
       result,
-      "1987-05-31 13:37:00 [INFO ] org.legogroup.woof.slf4j.Slf4jSuite: HELLO, ARRAYS! 1, Some(42), List(1337) (Slf4jSuite.scala:43)\n",
+      "1987-05-31 13:37:00 [INFO ] org.legogroup.woof.slf4j.Slf4jSuite: HELLO, ARRAYS! 1, Some(42), List(1337) (Slf4jSuite.scala:46)\n",
     )
     end for
   }
 
-  test("should respect log levels") {
+  dispatcher.test("should respect log levels") { implicit dispatcher =>
     given Printer   = NoColorPrinter(testFormatTime)
     given Filter    = Filter.exactLevel(LogLevel.Warn)
     given Clock[IO] = leetClock
@@ -65,12 +68,12 @@ class Slf4jSuite extends munit.CatsEffectSuite:
       result       <- stringWriter.get
     yield assertEquals(
       result,
-      "1987-05-31 13:37:00 [WARN ] org.legogroup.woof.slf4j.Slf4jSuite: WARN, SLF4J! (Slf4jSuite.scala:63)\n",
+      "1987-05-31 13:37:00 [WARN ] org.legogroup.woof.slf4j.Slf4jSuite: WARN, SLF4J! (Slf4jSuite.scala:66)\n",
     )
     end for
   }
 
-  test("should not fail on null throwable") {
+  dispatcher.test("should not fail on null throwable") { implicit dispatcher =>
     given Printer   = NoColorPrinter(testFormatTime)
     given Filter    = Filter.everything
     given Clock[IO] = leetClock
@@ -84,7 +87,7 @@ class Slf4jSuite extends munit.CatsEffectSuite:
       result       <- stringWriter.get
     yield assertEquals(
       result,
-      "1987-05-31 13:37:00 [DEBUG] org.legogroup.woof.slf4j.Slf4jSuite: null exception  (Slf4jSuite.scala:83)\n",
+      "1987-05-31 13:37:00 [DEBUG] org.legogroup.woof.slf4j.Slf4jSuite: null exception  (Slf4jSuite.scala:86)\n",
     )
     end for
   }
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1 @@
		org.legogroup.woof.slf4j2.WoofLoggerServiceProvider