JsonMarker#apply to use an Encoder on a scala object

marker/src/main/scala/io/github/nafg/cloudlogging/marker/BasicMarker.scala

@@ -0,0 +1,39 @@
+package io.github.nafg.cloudlogging.marker
+
+import org.slf4j.Marker
+
+import java.util
+import scala.jdk.CollectionConverters._
+
+// based on org.slf4j.helpers.BasicMarker
+private class BasicMarker(name: String, references: Seq[Marker])
+    extends Marker {
+  override def getName: String = name
+  override def add(reference: Marker): Unit =
+    throw new UnsupportedOperationException
+  override def hasReferences: Boolean = references.nonEmpty
+  //noinspection ScalaDeprecation
+  @deprecated override def hasChildren: Boolean = hasReferences
+  override def iterator: util.Iterator[Marker] = references.iterator.asJava
+  override def remove(referenceToRemove: Marker): Boolean =
+    throw new UnsupportedOperationException
+  override def contains(other: Marker): Boolean =
+    this == other || references.exists(_.contains(other))
+  override def contains(name: String): Boolean =
+    this.name == name || references.exists(_.contains(name))
+  override def equals(obj: AnyRef): Boolean =
+    if (this eq obj)
+      true
+    else if (obj == null)
+      false
+    else
+      obj match {
+        case other: Marker => name == other.getName
+        case _             => false
+      }
+  override def hashCode: Int = name.hashCode
+  override def toString: String =
+    getName +
+      (if (!this.hasReferences) ""
+       else " [ " + references.map(_.getName).mkString(", ") + " ]")
+}

marker/src/main/scala/io/github/nafg/cloudlogging/marker/JsonMarker.scala

@@ -1,20 +1,12 @@
 package io.github.nafg.cloudlogging.marker
 
-import scala.jdk.CollectionConverters._
-
-import io.circe.Json
+import io.circe.{Encoder, Json}
 import org.slf4j.Marker
 
-
-case class JsonMarker(name: String, data: Json, references: Marker*) extends Marker {
-  override def getName = name
-  override def add(reference: Marker): Unit = throw new NotImplementedError
-  override def remove(reference: Marker) = throw new NotImplementedError
-  override def hasChildren = hasReferences
-  override def hasReferences = references.nonEmpty
-  override def iterator() = references.asJava.iterator()
-  override def contains(other: Marker) =
-    this == other || references.exists(_.contains(other))
-  override def contains(name: String) =
-    this.name == name || references.exists(_.contains(name))
+case class JsonMarker(name: String, data: Json, references: Marker*)
+    extends BasicMarker(name, references)
+object JsonMarker {
+  def apply[A: Encoder](name: String,
+                        references: Marker*)(data: A): JsonMarker =
+    JsonMarker(name, Encoder[A].apply(data), references: _*)
 }