Cache descriptor defaults

CHANGELOG.md

@@ -4,6 +4,7 @@
 ### Added
 
 ### Changed
+- **API breaking** Descriptor no has a member property `defaultValue` instead of `defaultItem()` extension. It cahces default value state on the first call. It is done because computing default on each call is too expensive.
 
 ### Deprecated
 

build.gradle.kts

@@ -4,7 +4,7 @@ plugins {
 
 allprojects {
     group = "space.kscience"
-    version = "0.4.0"
+    version = "0.4.1"
 }
 
 subprojects {

dataforge-meta/api/dataforge-meta.api

@@ -501,15 +501,11 @@ public abstract interface class space/kscience/dataforge/meta/descriptors/Descri
 public final class space/kscience/dataforge/meta/descriptors/Described$Companion {
 }
 
-public final class space/kscience/dataforge/meta/descriptors/DescriptorMetaKt {
-	public static final fun defaultItem (Lspace/kscience/dataforge/meta/descriptors/ItemDescriptor;)Lspace/kscience/dataforge/meta/TypedMetaItem;
-	public static final fun defaultMeta (Lspace/kscience/dataforge/meta/descriptors/NodeDescriptor;)Lspace/kscience/dataforge/meta/Laminate;
-}
-
 public abstract interface class space/kscience/dataforge/meta/descriptors/ItemDescriptor : space/kscience/dataforge/meta/MetaRepr {
 	public static final field Companion Lspace/kscience/dataforge/meta/descriptors/ItemDescriptor$Companion;
 	public static final field DEFAULT_INDEX_KEY Ljava/lang/String;
 	public abstract fun getAttributes ()Lspace/kscience/dataforge/meta/Meta;
+	public abstract fun getDefaultValue ()Lspace/kscience/dataforge/meta/TypedMetaItem;
 	public abstract fun getIndexKey ()Ljava/lang/String;
 	public abstract fun getInfo ()Ljava/lang/String;
 	public abstract fun getMultiple ()Z
@@ -552,6 +548,7 @@ public final class space/kscience/dataforge/meta/descriptors/ItemDescriptorKt {
 
 public abstract interface class space/kscience/dataforge/meta/descriptors/NodeDescriptor : space/kscience/dataforge/meta/descriptors/ItemDescriptor {
 	public static final field Companion Lspace/kscience/dataforge/meta/descriptors/NodeDescriptor$Companion;
+	public fun defaultMeta ()Lspace/kscience/dataforge/meta/Laminate;
 	public abstract fun getDefault ()Lspace/kscience/dataforge/meta/Config;
 	public abstract fun getItems ()Ljava/util/Map;
 	public abstract fun getNodes ()Ljava/util/Map;
@@ -570,6 +567,7 @@ public final class space/kscience/dataforge/meta/descriptors/NodeDescriptorBuild
 	public synthetic fun build ()Lspace/kscience/dataforge/meta/descriptors/ItemDescriptor;
 	public fun build ()Lspace/kscience/dataforge/meta/descriptors/NodeDescriptor;
 	public fun getDefault ()Lspace/kscience/dataforge/meta/Config;
+	public fun getDefaultValue ()Lspace/kscience/dataforge/meta/TypedMetaItem;
 	public fun getItems ()Ljava/util/Map;
 	public fun getNodes ()Ljava/util/Map;
 	public fun getRequired ()Z
@@ -610,6 +608,7 @@ public final class space/kscience/dataforge/meta/descriptors/ValueDescriptorBuil
 	public final fun default (Ljava/lang/Object;)V
 	public fun getAllowedValues ()Ljava/util/List;
 	public fun getDefault ()Lspace/kscience/dataforge/values/Value;
+	public fun getDefaultValue ()Lspace/kscience/dataforge/meta/TypedMetaItem;
 	public fun getRequired ()Z
 	public fun getType ()Ljava/util/List;
 	public fun isAllowedValue (Lspace/kscience/dataforge/values/Value;)Z

dataforge-meta/src/commonMain/kotlin/space/kscience/dataforge/meta/Scheme.kt

@@ -1,6 +1,9 @@
 package space.kscience.dataforge.meta
 
-import space.kscience.dataforge.meta.descriptors.*
+import space.kscience.dataforge.meta.descriptors.Described
+import space.kscience.dataforge.meta.descriptors.NodeDescriptor
+import space.kscience.dataforge.meta.descriptors.get
+import space.kscience.dataforge.meta.descriptors.validateItem
 import space.kscience.dataforge.names.Name
 import space.kscience.dataforge.names.NameToken
 import space.kscience.dataforge.names.asName
@@ -53,7 +56,7 @@ public open class Scheme() : Described, MetaRepr, ItemPropertyProvider {
     }
 
     private fun getDefaultItem(name: Name): MetaItem? {
-        return default?.get(name) ?: descriptor?.get(name)?.defaultItem()
+        return default?.get(name) ?: descriptor?.get(name)?.defaultValue
     }
 
     /**
@@ -94,7 +97,7 @@ public open class Scheme() : Described, MetaRepr, ItemPropertyProvider {
                 descriptor?.items?.forEach { (key, itemDescriptor) ->
                     val token = NameToken(key)
                     val name = token.asName()
-                    val item = default?.get(name) ?: itemDescriptor.defaultItem()
+                    val item = default?.get(name) ?: itemDescriptor.defaultValue
                     if (item != null) {
                         put(token, item)
                     }

dataforge-meta/src/commonMain/kotlin/space/kscience/dataforge/meta/descriptors/DescriptorMeta.kt

@@ -1,47 +0,0 @@
-package space.kscience.dataforge.meta.descriptors
-
-import space.kscience.dataforge.meta.*
-import space.kscience.dataforge.names.NameToken
-
-/**
- * A [Meta] that is constructed from [NodeDescriptor]
- */
-private class DescriptorMeta(val descriptor: NodeDescriptor) : Meta, MetaBase() {
-    override val items: Map<NameToken, MetaItem>
-        get() = buildMap {
-            descriptor.items.forEach { (token, descriptorItem) ->
-                val item = descriptorItem.defaultItem()
-                if (item != null) {
-                    put(NameToken(token), item)
-                }
-            }
-        }
-}
-
-/**
- * Generate a laminate representing default item set generated by this descriptor
- */
-public fun NodeDescriptor.defaultMeta(): Laminate = Laminate(default, DescriptorMeta(this))
-
-/**
- * Build a default [MetaItemNode] from this node descriptor
- */
-internal fun NodeDescriptor.defaultItem(): MetaItemNode<*> =
-    MetaItemNode(defaultMeta())
-
-/**
- * Build a default [MetaItemValue] from this descriptor
- */
-internal fun ValueDescriptor.defaultItem(): MetaItemValue? {
-    return MetaItemValue(default ?: return null)
-}
-
-/**
- * Build a default [TypedMetaItem] from descriptor.
- */
-public fun ItemDescriptor.defaultItem(): MetaItem? {
-    return when (this) {
-        is ValueDescriptor -> defaultItem()
-        is NodeDescriptor -> defaultItem()
-    }
-}

dataforge-meta/src/commonMain/kotlin/space/kscience/dataforge/meta/descriptors/ItemDescriptor.kt

@@ -37,6 +37,11 @@ public sealed interface ItemDescriptor: MetaRepr {
      */
     public val indexKey: String
 
+    /**
+     * Compute and cache the default [MetaItem] value described by this descriptor
+     */
+    public val defaultValue: MetaItem?
+
     public companion object {
         public const val DEFAULT_INDEX_KEY: String = "@index"
     }

dataforge-meta/src/commonMain/kotlin/space/kscience/dataforge/meta/descriptors/NodeDescriptor.kt

@@ -5,6 +5,22 @@ import space.kscience.dataforge.misc.DFBuilder
 import space.kscience.dataforge.names.*
 
 
+/**
+ * A [Meta] that is constructed from [NodeDescriptor]
+ */
+private class DescriptorMeta(val descriptor: NodeDescriptor) : Meta, MetaBase() {
+    override val items: Map<NameToken, MetaItem>
+        get() = buildMap {
+            descriptor.items.forEach { (token, descriptorItem) ->
+                val item = descriptorItem.defaultValue
+                if (item != null) {
+                    put(NameToken(token), item)
+                }
+            }
+        }
+}
+
+
 /**
  * Descriptor for meta node. Could contain additional information for viewing
  * and editing.
@@ -12,7 +28,7 @@ import space.kscience.dataforge.names.*
  * @author Alexander Nozik
  */
 @DFBuilder
-public sealed interface NodeDescriptor: ItemDescriptor {
+public sealed interface NodeDescriptor : ItemDescriptor {
     /**
      * True if the node is required
      *
@@ -42,6 +58,11 @@ public sealed interface NodeDescriptor: ItemDescriptor {
      */
     public val values: Map<String, ValueDescriptor>
 
+    /**
+     * Generate a laminate representing default item set generated by this descriptor
+     */
+    public fun defaultMeta(): Laminate = Laminate(default, DescriptorMeta(this))
+
     public companion object {
 
         internal val ITEM_KEY: Name = "item".asName()
@@ -166,6 +187,11 @@ public class NodeDescriptorBuilder(config: Config = Config()) : ItemDescriptorBu
         value(name.toName(), block)
     }
 
+    /**
+     * Build a default [MetaItemNode] from this node descriptor
+     */
+    override val defaultValue: MetaItem by lazy { MetaItemNode(defaultMeta()) }
+
     override fun build(): NodeDescriptor = NodeDescriptorBuilder(config.copy())
 
     public companion object {

dataforge-meta/src/commonMain/kotlin/space/kscience/dataforge/meta/descriptors/ValueDescriptor.kt

@@ -131,5 +131,7 @@ public class ValueDescriptorBuilder(config: Config = Config()) : ItemDescriptorB
         this.allowedValues = v.map { Value.of(it) }
     }
 
+    override val defaultValue: MetaItem? get() = default?.asMetaItem()
+
     override fun build(): ValueDescriptor = ValueDescriptorBuilder(config.copy())
 }