Remove log4s usage in http4s-server integration (#3663)

Co-authored-by: Henry Genet <henry.genet@swisscom.com>

client/testserver/src/main/scala/sttp/tapir/client/tests/HttpServer.scala

@@ -12,7 +12,8 @@ import org.http4s.blaze.server.BlazeServerBuilder
 import org.http4s.server.middleware._
 import org.http4s.server.websocket.WebSocketBuilder2
 import org.http4s.websocket.WebSocketFrame
-import org.http4s.{multipart, _}
+import org.http4s._
+import org.slf4j.LoggerFactory
 import org.typelevel.ci.CIString
 import scodec.bits.ByteVector
 import sttp.tapir.client.tests.HttpServer._
@@ -30,7 +31,7 @@ object HttpServer {
 
 class HttpServer(port: Port) {
 
-  private val logger = org.log4s.getLogger
+  private val logger = LoggerFactory.getLogger(getClass)
 
   private var stopServer: IO[Unit] = _
 

server/http4s-server/src/main/scalajvm/sttp/tapir/server/http4s/Http4sDefaultServerLog.scala

@@ -1,25 +1,26 @@
 package sttp.tapir.server.http4s
 
 import cats.effect.Sync
+import org.typelevel.log4cats.Logger
+import org.typelevel.log4cats.slf4j.Slf4jLogger
 import sttp.tapir.server.interceptor.log.DefaultServerLog
-import org.log4s.{Logger, getLogger}
 
 object Http4sDefaultServerLog {
-  private[http4s] val log: Logger = getLogger
 
   def apply[F[_]: Sync]: DefaultServerLog[F] = {
+    val log = Slf4jLogger.getLogger[F]
     DefaultServerLog(
-      doLogWhenReceived = debugLog(_, None),
-      doLogWhenHandled = debugLog[F],
-      doLogAllDecodeFailures = debugLog[F],
-      doLogExceptions = (msg: String, ex: Throwable) => Sync[F].delay(log.error(ex)(msg)),
+      doLogWhenReceived = msg => debugLog(log)(msg, None),
+      doLogWhenHandled = debugLog(log),
+      doLogAllDecodeFailures = debugLog(log),
+      doLogExceptions = (msg: String, ex: Throwable) => log.error(ex)(msg),
       noLog = Sync[F].pure(())
     )
   }
 
-  private def debugLog[F[_]](msg: String, exOpt: Option[Throwable])(implicit sync: Sync[F]): F[Unit] =
+  private def debugLog[F[_]](log: Logger[F])(msg: String, exOpt: Option[Throwable]): F[Unit] =
     exOpt match {
-      case None     => Sync[F].delay(log.debug(msg))
-      case Some(ex) => Sync[F].delay(log.debug(ex)(msg))
+      case None     => log.debug(msg)
+      case Some(ex) => log.debug(ex)(msg)
     }
 }