Move logging to kernel-only dependency (#710)

* Kernelize Atom and QVar

* Fix tuple syntax for 2.12

* Move logging to kernel-only dependency

build.sbt

@@ -84,7 +84,6 @@ lazy val loggingStr = project
     defaultSettings,
     libraryDependencies ++= Seq(
       catsCore,
-      catsEffect,
       circeCore,
       tethys,
       tethysJackson,
@@ -95,7 +94,7 @@ lazy val loggingStr = project
       catsTagless
     ),
   )
-  .dependsOn(core, concurrent)
+  .dependsOn(kernel)
 
 lazy val loggingDer = project
   .in(file("modules/logging/derivation"))
@@ -111,7 +110,7 @@ lazy val loggingLayout = project
   .in(file("modules/logging/layout"))
   .settings(
     defaultSettings,
-    libraryDependencies ++= Seq(catsCore, catsEffect, logback, slf4j),
+    libraryDependencies ++= Seq(catsCore, logback, slf4j),
     name := "tofu-logging-layout"
   )
   .dependsOn(loggingStr)
@@ -121,9 +120,9 @@ lazy val loggingUtil = project
   .settings(
     defaultSettings,
     name := "tofu-logging-util",
-    libraryDependencies += slf4j,
+    libraryDependencies ++= Vector(slf4j, catsEffect),
   )
-  .dependsOn(loggingStr, concurrent)
+  .dependsOn(loggingStr)
 
 lazy val loggingShapeless = project
   .in(file("modules/logging/interop/shapeless"))

modules/logging/structured/src/main/scala/tofu/logging/LogTree.scala

@@ -1,73 +1,79 @@
 package tofu.logging
 
-import cats.effect.SyncIO
-import cats.effect.concurrent.Ref
 import cats.instances.list._
 import cats.instances.unit._
 import tofu.syntax.monadic._
 import cats.syntax.foldable._
 import cats.syntax.traverse._
+import scala.collection.mutable
 
 import cats.{Applicative, Monoid}
 import io.circe.Json
+import cats.Eval
 
 sealed trait LogTree {
   import LogTree._
-  def json: SyncIO[Json] = this match {
-    case LogDict(values)      =>
-      values.get.flatMap { d => d.toList.traverse { case (name, t) => t.json.map(name -> _) }.map(Json.obj(_: _*)) }
+  def json: Eval[Json] = this match {
+    case dict: LogDict        =>
+      dict.getList.flatMap { _.traverse { case (name, t) => t.json.map(name -> _) }.map(Json.obj(_: _*)) }
     case LogArr(items)        => items.toList.traverse(_.json).map(Json.arr(_: _*))
-    case value: LogParamValue => value.jsonVal.pure[SyncIO]
+    case value: LogParamValue => value.jsonVal.pure[Eval]
   }
 }
 
+// pretty much unsafe mutable builder for circe.Json from logs
 object LogTree extends LogBuilder[Json] {
   implicit def monoid: Monoid[Output] = Applicative.monoid
 
-  type Output = SyncIO[Unit]
-  type ValRes = SyncIO[Boolean]
-  type Value  = Ref[SyncIO, LogTree]
-  type Top    = LogDict
+  type Output = Eval[Unit]
+  type ValRes = Eval[Boolean]
+  class Value(private var tree: LogTree) {
+    def get                 = Eval.always(tree)
+    def set(value: LogTree) = Eval.always { tree = value }
+  }
+  type Top = LogDict
 
-  final case class LogDict(values: Ref[SyncIO, Map[String, LogTree]]) extends LogTree {
-    def add(name: String, tree: LogTree): SyncIO[Unit] = values update (_ + (name -> tree))
+  class LogDict(private val values: mutable.Map[String, LogTree]) extends LogTree {
+    def add(name: String, tree: LogTree): Eval[Unit] = Eval.always(values.update(name, tree))
+    def getList: Eval[List[(String, LogTree)]]       = Eval.always(values.toList)
   }
 
   final case class LogArr(values: Iterable[LogTree]) extends LogTree
 
-  private val newdict = Ref[SyncIO].of(Map.empty[String, LogTree]).map(LogDict)
-  private val newtree = Ref[SyncIO].of(NullValue: LogTree)
+  private val newdict = Eval.always(mutable.Map.empty[String, LogTree]).map(new LogDict(_))
+  private val newtree = Eval.always(new Value(NullValue))
 
   val receiver: LogRenderer[LogDict, Value, Output, ValRes] = new LogRenderer[LogDict, Value, Output, ValRes] {
 
-    def coalesce(f: Value => ValRes, g: Value => ValRes, v: Value): ValRes                                =
-      f(v).flatMap(written => if (written) SyncIO(true) else g(v))
-    def zero(v: Ref[SyncIO, LogTree]): SyncIO[Boolean]                                                    = SyncIO(false)
-    def noop(i: LogDict): SyncIO[Unit]                                                                    = SyncIO.unit
-    def combine(x: SyncIO[Unit], y: SyncIO[Unit]): SyncIO[Unit]                                           = x *> y
-    def putValue(value: LogParamValue, input: Ref[SyncIO, LogTree]): SyncIO[Boolean]                      = input.set(value) as true
-    def sub(name: String, input: LogDict)(receive: Ref[SyncIO, LogTree] => SyncIO[Boolean]): SyncIO[Unit] =
+    def coalesce(f: Value => ValRes, g: Value => ValRes, v: Value): ValRes =
+      f(v).flatMap(written => if (written) Eval.now(true) else g(v))
+    def zero(v: Value): Eval[Boolean]                                      = Eval.now(false)
+    def noop(i: LogDict): Eval[Unit]                                       = Eval.now(())
+    def combine(x: Eval[Unit], y: Eval[Unit]): Eval[Unit]                  = x *> y
+    def putValue(value: LogParamValue, input: Value): Eval[Boolean]        = input.set(value) as true
+
+    def sub(name: String, input: LogDict)(receive: Value => Eval[Boolean]): Eval[Unit] =
       for {
         t <- newtree
         _ <- receive(t)
         v <- t.get
         _ <- input.add(name, v)
       } yield ()
 
-    def list(size: Int, input: Ref[SyncIO, LogTree])(receive: (Value, Int) => SyncIO[Boolean]): SyncIO[Boolean] =
+    def list(size: Int, input: Value)(receive: (Value, Int) => Eval[Boolean]): Eval[Boolean] =
       for {
         ts <- newtree.replicateA(size)
         _  <- ts.zipWithIndex.traverse_(receive.tupled)
         vs <- ts.traverse(_.get)
         _  <- input.set(LogArr(vs))
       } yield true
-    def dict(input: Ref[SyncIO, LogTree])(receive: LogDict => SyncIO[Unit]): SyncIO[Boolean]                    =
+    def dict(input: Value)(receive: LogDict => Eval[Unit]): Eval[Boolean]                    =
       newdict flatMap input.set as true
   }
 
-  def buildJson(buildTree: LogDict => Output): SyncIO[Json] = newdict flatTap buildTree flatMap (_.json)
+  def buildJson(buildTree: LogDict => Output): Eval[Json] = newdict flatTap buildTree flatMap (_.json)
 
-  def make(f: LogDict => SyncIO[Unit]): Json = buildJson(f).unsafeRunSync()
+  def make(f: LogDict => Eval[Unit]): Json = buildJson(f).value
 }
 
 sealed trait LogParamValue extends LogTree {

modules/logging/structured/src/main/scala/tofu/logging/LoggableContext.scala

@@ -11,7 +11,7 @@ trait LoggableContext[F[_]] {
 object LoggableContext {
   def of[F[_]] = new LoggableContextPA[F]
   private[logging] final class LoggableContextPA[F[_]](private val dummy: Boolean = true) extends AnyVal {
-    def instance[C](implicit ctx: F HasContext C, ctxLog: Loggable[C]): LoggableContext[F] = new LoggableContext[F] {
+    def instance[C](implicit ctx: F WithContext C, ctxLog: Loggable[C]): LoggableContext[F] = new LoggableContext[F] {
       type Ctx = C
       val loggable: Loggable[C]    = ctxLog
       val context: F WithContext C = ctx.asWithContext

modules/logging/structured/src/main/scala/tofu/logging/Logs.scala

@@ -1,7 +1,6 @@
 package tofu.logging
 
 import cats.data.Tuple2K
-import cats.effect.Sync
 import cats.kernel.Monoid
 import cats.tagless.syntax.functorK._
 import cats.tagless.{ApplyK, FunctorK}
@@ -24,6 +23,7 @@ import tofu.logging.impl.UniversalLogs
 import tofu.Delay
 import tofu.WithContext
 import tofu.logging.impl.UniversalContextLogs
+import tofu.concurrent.MakeQVar
 
 /** A helper for creating instances of [[tofu.logging.Logging]], defining a way these instances will behave while doing logging.
   * Can create instances either on a by-name basic or a type tag basic.
@@ -88,21 +88,21 @@ object Logs extends LogsInstances0 {
   /** Returns an instance of [[tofu.logging.Logs]] that requires [[cats.effect.Sync]] to perform logging side-effects.
     * Has no notion of context.
     */
-  def sync[I[_]: Sync, F[_]: Sync]: Logs[I, F] = new Logs[I, F] {
-    def byName(name: String): I[Logging[F]] = Sync[I].delay(new SyncLogging[F](LoggerFactory.getLogger(name)))
+  def sync[I[_]: Delay, F[_]: Delay: Monad]: Logs[I, F] = new Logs[I, F] {
+    def byName(name: String): I[Logging[F]] = Delay[I].delay(new SyncLogging[F](LoggerFactory.getLogger(name)))
   }
 
   def universal[F[_]: Delay]: Logs.Universal[F]                                                      = new UniversalLogs
   def contextual[F[_]: FlatMap: Delay, C: Loggable](implicit FC: F WithContext C): Logs.Universal[F] =
     new UniversalContextLogs[F, C]
 
-  def withContext[I[_]: Sync, F[_]: Sync](implicit ctx: LoggableContext[F]): Logs[I, F] = {
+  def withContext[I[_]: Delay, F[_]: Monad: Delay](implicit ctx: LoggableContext[F]): Logs[I, F] = {
     import ctx.loggable
     new Logs[I, F] {
       override def forService[Svc: ClassTag]: I[Logging[F]] =
-        Sync[I].delay(new ContextSyncLoggingImpl[F, ctx.Ctx](ctx.context, loggerForService[Svc]))
+        Delay[I].delay(new ContextSyncLoggingImpl[F, ctx.Ctx](ctx.context, loggerForService[Svc]))
       override def byName(name: String): I[Logging[F]]      =
-        Sync[I].delay(new ContextSyncLoggingImpl[F, ctx.Ctx](ctx.context, LoggerFactory.getLogger(name)))
+        Delay[I].delay(new ContextSyncLoggingImpl[F, ctx.Ctx](ctx.context, LoggerFactory.getLogger(name)))
     }
   }
 
@@ -138,7 +138,7 @@ object Logs extends LogsInstances0 {
   }
 
   final implicit class LogsOps[I[_], F[_]](private val logs: Logs[I, F]) extends AnyVal {
-    def cached(implicit IM: Monad[I], IQ: QVars[I], IG: Guarantee[I]): I[Logs[I, F]] =
+    def cached(implicit IM: Monad[I], IQ: MakeQVar[I, I], IG: Guarantee[I]): I[Logs[I, F]] =
       QVars[I]
         .of(Map.empty[String, Logging[F]])
         .map2(
@@ -149,7 +149,7 @@ object Logs extends LogsInstances0 {
 
     def cachedUniversal(implicit
         IM: Monad[I],
-        IQ: QVars[I],
+        IQ: MakeQVar[I, I],
         IG: Guarantee[I],
         il: Lift[I, F],
         F: FlatMap[F]

modules/logging/structured/src/main/scala/tofu/logging/impl/CachedLogs.scala

@@ -3,7 +3,7 @@ import cats.Monad
 import tofu.Guarantee
 import tofu.concurrent.QVar
 import tofu.logging.{LoggedValue, Logging, Logs}
-import tofu.syntax.bracket._
+import tofu.syntax.guarantee._
 import tofu.syntax.monadic._
 
 import scala.reflect.{ClassTag, classTag}

modules/logging/structured/src/main/scala/tofu/logging/impl/ContextLoggingImpl.scala

@@ -6,7 +6,7 @@ import cats.Applicative
 import cats.syntax.applicative._
 import org.slf4j.{Logger, Marker}
 
-class ContextLoggingImpl[F[_]: Applicative, C: Loggable, Service](context: F HasContext C, logger: Logger)
+class ContextLoggingImpl[F[_]: Applicative, C: Loggable, Service](context: F WithContext C, logger: Logger)
     extends LoggingImpl[F](logger) {
 
   override def trace(message: String, values: LoggedValue*) =

modules/logging/structured/src/main/scala/tofu/logging/impl/ContextSyncLoggingImpl.scala

@@ -2,11 +2,11 @@ package tofu
 package logging
 package impl
 
-import cats.effect.Sync
-import cats.syntax.applicative._
 import org.slf4j.{Logger, Marker}
+import tofu.syntax.monadic._
+import cats.Monad
 
-class ContextSyncLoggingImpl[F[_], C: Loggable](context: F HasContext C, logger: Logger)(implicit F: Sync[F])
+class ContextSyncLoggingImpl[F[_]: Monad, C: Loggable](context: F WithContext C, logger: Logger)(implicit F: Delay[F])
     extends LoggingImpl[F](logger) {
 
   override def trace(message: String, values: LoggedValue*) =

modules/logging/structured/src/main/scala/tofu/logging/impl/SyncLogging.scala

@@ -1,11 +1,12 @@
 package tofu.logging
 package impl
 
-import cats.effect.Sync
-import cats.syntax.applicative._
 import org.slf4j.{Logger, Marker}
+import tofu.syntax.monadic._
+import cats.Monad
+import tofu.Delay
 
-class SyncLogging[F[_]](logger: Logger)(implicit F: Sync[F]) extends LoggingImpl[F](logger) {
+class SyncLogging[F[_]: Monad](logger: Logger)(implicit F: Delay[F]) extends LoggingImpl[F](logger) {
   override def trace(message: String, values: LoggedValue*): F[Unit] =
     F.delay(logger.trace(message, values: _*)).whenA(traceEnabled)
   override def debug(message: String, values: LoggedValue*): F[Unit] =

modules/logging/structured/src/test/scala/tofu/logging/LoggableContextSuite.scala

@@ -1,17 +1,18 @@
 package tofu.logging
 
-import tofu.HasContext
 import tofu.compat.unused
+import tofu.WithContext
 
 object LoggableContextSuite {
 
-  def summonInstance[R: Loggable, F[_]: *[_] HasContext R](): Unit = {
+  def summonInstance[R: Loggable, F[_]: *[_] WithContext R](): Unit = {
     LoggableContext.of[F].instance
     ()
   }
 
   @unused
-  def summonInstanceUnambiguously[R1: Loggable, R2: Loggable, F[_]: *[_] HasContext R1: *[_] HasContext R2](): Unit = {
+  def summonInstanceUnambiguously[R1: Loggable, R2: Loggable, F[_]: *[_] WithContext R1: *[_] WithContext R2]()
+      : Unit = {
     LoggableContext.of[F].instance[R1]
     ()
   }