Use JSON as the format for the Kotlin project structure metadata

libraries/tools/kotlin-gradle-plugin-integration-tests/src/test/kotlin/org/jetbrains/kotlin/gradle/HierarchicalMppIT.kt

@@ -5,8 +5,8 @@
 
 package org.jetbrains.kotlin.gradle
 
-import org.jetbrains.kotlin.gradle.internals.MULTIPLATFORM_PROJECT_METADATA_FILE_NAME
+import org.jetbrains.kotlin.gradle.internals.MULTIPLATFORM_PROJECT_METADATA_JSON_FILE_NAME
-import org.jetbrains.kotlin.gradle.internals.parseKotlinSourceSetMetadataFromXml
+import org.jetbrains.kotlin.gradle.internals.parseKotlinSourceSetMetadataFromJson
 import org.jetbrains.kotlin.gradle.plugin.KotlinJsCompilerType
 import org.jetbrains.kotlin.gradle.plugin.mpp.KotlinProjectStructureMetadata
 import org.jetbrains.kotlin.gradle.plugin.mpp.ModuleDependencyIdentifier
@@ -16,7 +16,6 @@ import org.jetbrains.kotlin.gradle.util.checkedReplace
 import org.jetbrains.kotlin.gradle.util.modify
 import java.io.File
 import java.util.zip.ZipFile
-import javax.xml.parsers.DocumentBuilderFactory
 import kotlin.test.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertTrue
@@ -216,7 +215,7 @@ class HierarchicalMppIT : BaseGradleIT() {
             )
         ).use { publishedMetadataJar ->
             publishedMetadataJar.checkAllEntryNamesArePresent(
-                "META-INF/$MULTIPLATFORM_PROJECT_METADATA_FILE_NAME",
+                "META-INF/$MULTIPLATFORM_PROJECT_METADATA_JSON_FILE_NAME",
 
                 "commonMain/default/manifest",
                 "commonMain/default/linkdata/package_com.example/",
@@ -254,7 +253,7 @@ class HierarchicalMppIT : BaseGradleIT() {
             )
         ).use { publishedMetadataJar ->
             publishedMetadataJar.checkAllEntryNamesArePresent(
-                "META-INF/$MULTIPLATFORM_PROJECT_METADATA_FILE_NAME",
+                "META-INF/$MULTIPLATFORM_PROJECT_METADATA_JSON_FILE_NAME",
 
                 "commonMain/default/manifest",
                 "commonMain/default/linkdata/package_com.example.bar/",
@@ -441,10 +440,8 @@ class HierarchicalMppIT : BaseGradleIT() {
     }
 
     private fun ZipFile.getProjectStructureMetadata(): KotlinProjectStructureMetadata {
-        val documentBuilder = DocumentBuilderFactory.newInstance().newDocumentBuilder()
+        val json = getInputStream(getEntry("META-INF/$MULTIPLATFORM_PROJECT_METADATA_JSON_FILE_NAME")).reader().readText()
-        val document = getInputStream(getEntry("META-INF/$MULTIPLATFORM_PROJECT_METADATA_FILE_NAME"))
+        return checkNotNull(parseKotlinSourceSetMetadataFromJson(json))
-            .use { inputStream -> documentBuilder.parse(inputStream) }
-        return checkNotNull(parseKotlinSourceSetMetadataFromXml(document))
     }
 
     @Test

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/plugin/mpp/GenerateProjectStructureMetadata.kt

@@ -26,19 +26,15 @@ open class GenerateProjectStructureMetadata : DefaultTask() {
 
     @get:OutputFile
     val resultXmlFile: File
-        get() = project.buildDir.resolve("kotlinProjectStructureMetadata/$MULTIPLATFORM_PROJECT_METADATA_FILE_NAME")
+        get() = project.buildDir.resolve("kotlinProjectStructureMetadata/$MULTIPLATFORM_PROJECT_METADATA_JSON_FILE_NAME")
 
     @TaskAction
     fun generateMetadataXml() {
         resultXmlFile.parentFile.mkdirs()
-
+        val resultString = kotlinProjectStructureMetadata.toJson()
-        val document = kotlinProjectStructureMetadata.toXmlDocument()
+        resultXmlFile.writeText(resultString)
-
-        TransformerFactory.newInstance().newTransformer().apply {
-            setOutputProperty(OutputKeys.INDENT, "yes")
-            setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "4")
-        }.transform(DOMSource(document), StreamResult(resultXmlFile))
     }
 }
 
 internal const val MULTIPLATFORM_PROJECT_METADATA_FILE_NAME = "kotlin-project-structure-metadata.xml"
+internal const val MULTIPLATFORM_PROJECT_METADATA_JSON_FILE_NAME = "kotlin-project-structure-metadata.json"

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/plugin/mpp/GranularMetadataTransformation.kt

@@ -17,6 +17,7 @@ import org.jetbrains.kotlin.gradle.plugin.KotlinSourceSet
 import org.jetbrains.kotlin.gradle.plugin.sources.KotlinDependencyScope
 import org.jetbrains.kotlin.gradle.plugin.sources.sourceSetDependencyConfigurationByScope
 import java.io.File
+import java.io.InputStream
 import java.util.*
 import java.util.zip.ZipEntry
 import java.util.zip.ZipFile
@@ -344,16 +345,20 @@ private class JarArtifactMppDependencyMetadataExtractor(
 
     val metadataArtifactBySourceSet: MutableMap<String, File> = mutableMapOf()
 
+    private fun parseJsonProjectStructureMetadata(input: InputStream) =
+        parseKotlinSourceSetMetadataFromJson(input.reader().readText())
+
+    private fun parseXmlProjectStructureMetadata(input: InputStream) =
+        parseKotlinSourceSetMetadataFromXml(DocumentBuilderFactory.newInstance().newDocumentBuilder().parse(input))
+
     override fun getProjectStructureMetadata(): KotlinProjectStructureMetadata? {
         return ZipFile(primaryArtifact).use { zip ->
-            val metadata = zip.getEntry("META-INF/$MULTIPLATFORM_PROJECT_METADATA_FILE_NAME")
+            val (metadata, parseFunction) =
-                ?: return null
+                zip.getEntry("META-INF/$MULTIPLATFORM_PROJECT_METADATA_JSON_FILE_NAME")?.to(::parseJsonProjectStructureMetadata)
+                    ?: zip.getEntry("META-INF/$MULTIPLATFORM_PROJECT_METADATA_FILE_NAME")?.to(::parseXmlProjectStructureMetadata)
+                    ?: return null
 
-            val metadataXmlDocument = zip.getInputStream(metadata).use { inputStream ->
+            zip.getInputStream(metadata).use(parseFunction)
-                DocumentBuilderFactory.newInstance().newDocumentBuilder().parse(inputStream)
-            }
-
-            parseKotlinSourceSetMetadataFromXml(metadataXmlDocument)
         }
     }
 

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/plugin/mpp/KotlinProjectStructureMetadata.kt

@@ -5,6 +5,10 @@
 
 package org.jetbrains.kotlin.gradle.plugin.mpp
 
+import com.google.gson.GsonBuilder
+import com.google.gson.JsonObject
+import com.google.gson.JsonParser
+import com.google.gson.stream.JsonWriter
 import org.gradle.api.Project
 import org.gradle.api.tasks.Input
 import org.gradle.api.tasks.Internal
@@ -18,6 +22,7 @@ import org.w3c.dom.Document
 import org.w3c.dom.Element
 import org.w3c.dom.Node
 import org.w3c.dom.NodeList
+import java.io.StringWriter
 import javax.xml.parsers.DocumentBuilderFactory
 
 data class ModuleDependencyIdentifier(
@@ -34,6 +39,8 @@ sealed class SourceSetMetadataLayout(
     object METADATA : SourceSetMetadataLayout("metadata", "jar")
     object KLIB : SourceSetMetadataLayout("klib", "klib")
 
+    override fun toString(): String = name
+
     companion object {
         private val values = listOf(METADATA, KLIB)
 
@@ -119,41 +126,40 @@ internal fun buildKotlinProjectStructureMetadata(project: Project): KotlinProjec
     )
 }
 
-internal fun KotlinProjectStructureMetadata.toXmlDocument(): Document {
+internal fun <Serializer> KotlinProjectStructureMetadata.serialize(
-    return DocumentBuilderFactory.newInstance().newDocumentBuilder().newDocument().apply {
+    serializer: Serializer,
-        fun Node.node(name: String, action: Element.() -> Unit) = appendChild(createElement(name).apply(action))
+    node: Serializer.(name: String, Serializer.() -> Unit) -> Unit,
-        fun Node.textNode(name: String, value: String) =
+    multiNodes: Serializer.(name: String, Serializer.() -> Unit) -> Unit,
-            appendChild(createElement(name).apply { appendChild(createTextNode(value)) })
+    multiNodesItem: Serializer.(name: String, Serializer.() -> Unit) -> Unit,
+    value: Serializer.(key: String, value: String) -> Unit,
+    multiValue: Serializer.(name: String, values: List<String>) -> Unit
+) = with(serializer) {
+    node(ROOT_NODE_NAME) {
+        value(FORMAT_VERSION_NODE_NAME, formatVersion)
 
-        node(ROOT_NODE_NAME) {
+        multiNodes(VARIANTS_NODE_NAME) {
-            textNode(FORMAT_VERSION_NODE_NAME, formatVersion)
+            sourceSetNamesByVariantName.forEach { (variantName, sourceSets) ->
-
+                multiNodesItem(VARIANT_NODE_NAME) {
-            node(VARIANTS_NODE_NAME) {
+                    value(NAME_NODE_NAME, variantName)
-                sourceSetNamesByVariantName.forEach { (variantName, sourceSets) ->
+                    multiValue(SOURCE_SET_NODE_NAME, sourceSets.toList())
-                    node(VARIANT_NODE_NAME) {
-                        textNode(NAME_NODE_NAME, variantName)
-                        sourceSets.forEach { sourceSetName -> textNode(SOURCE_SET_NODE_NAME, sourceSetName) }
-                    }
                 }
             }
+        }
 
-            node(SOURCE_SETS_NODE_NAME) {
+        multiNodes(SOURCE_SETS_NODE_NAME) {
-                val keys = sourceSetsDependsOnRelation.keys + sourceSetModuleDependencies.keys
+            val keys = sourceSetsDependsOnRelation.keys + sourceSetModuleDependencies.keys
-                for (sourceSet in keys) {
+            for (sourceSet in keys) {
-                    node(SOURCE_SET_NODE_NAME) {
+                multiNodesItem(SOURCE_SET_NODE_NAME) {
-                        textNode(NAME_NODE_NAME, sourceSet)
+                    value(NAME_NODE_NAME, sourceSet)
-                        sourceSetsDependsOnRelation[sourceSet].orEmpty().forEach { dependsOn ->
+                    multiValue(DEPENDS_ON_NODE_NAME, sourceSetsDependsOnRelation[sourceSet].orEmpty().toList())
-                            textNode(DEPENDS_ON_NODE_NAME, dependsOn)
+                    multiValue(MODULE_DEPENDENCY_NODE_NAME, sourceSetModuleDependencies[sourceSet].orEmpty().map { moduleDependency ->
-                        }
+                        moduleDependency.groupId + ":" + moduleDependency.moduleId
-                        sourceSetModuleDependencies[sourceSet].orEmpty().forEach { moduleDependency ->
+                    })
-                            textNode(MODULE_DEPENDENCY_NODE_NAME, moduleDependency.groupId + ":" + moduleDependency.moduleId)
+                    sourceSetBinaryLayout[sourceSet]?.let { binaryLayout ->
-                        }
+                        value(BINARY_LAYOUT_NODE_NAME, binaryLayout.name)
-                        sourceSetBinaryLayout[sourceSet]?.let { binaryLayout ->
+                    }
-                            textNode(BINARY_LAYOUT_NODE_NAME, binaryLayout.name)
+                    if (sourceSet in hostSpecificSourceSets) {
-                        }
+                        value(HOST_SPECIFIC_NODE_NAME, "true")
-                        if (sourceSet in hostSpecificSourceSets) {
-                            textNode(HOST_SPECIFIC_NODE_NAME, "true")
-                        }
                     }
                 }
             }
@@ -161,21 +167,76 @@ internal fun KotlinProjectStructureMetadata.toXmlDocument(): Document {
     }
 }
 
+internal fun KotlinProjectStructureMetadata.toXmlDocument(): Document {
+    return DocumentBuilderFactory.newInstance().newDocumentBuilder().newDocument().apply {
+        val node: Node.(String, Node.() -> Unit) -> Unit = { name, content -> appendChild(createElement(name).apply(content)) }
+        val textNode: Node.(String, String) -> Unit =
+            { name, value -> appendChild(createElement(name).apply { appendChild(createTextNode(value)) }) }
+        serialize(this as Node, node, node, node, textNode, { name, values -> for (v in values) textNode(name, v) })
+    }
+}
+
+internal fun KotlinProjectStructureMetadata.toJson(): String {
+    val gson = GsonBuilder().setPrettyPrinting().create()
+    val stringWriter = StringWriter()
+    with(gson.newJsonWriter(stringWriter)) {
+        val obj: JsonWriter.(String, JsonWriter.() -> Unit) -> Unit =
+            { name, content -> if (name.isNotEmpty()) name(name); beginObject(); content(); endObject() }
+        val property: JsonWriter.(String, String) -> Unit = { name, value -> name(name); value(value) }
+        val array: JsonWriter.(String, JsonWriter.() -> Unit) -> Unit =
+            { name, contents -> name(name); beginArray(); contents(); endArray() }
+
+        beginObject()
+        serialize(this, obj, array, { _, fn -> obj("", fn) }, property, { key, values -> array(key) { values.forEach { value(it) } } })
+        endObject()
+    }
+    return stringWriter.toString()
+}
+
 private val NodeList.elements: Iterable<Element> get() = (0 until length).map { this@elements.item(it) }.filterIsInstance<Element>()
 
+internal fun parseKotlinSourceSetMetadataFromJson(string: String): KotlinProjectStructureMetadata? {
+    @Suppress("DEPRECATION") // The replacement doesn't compile against old dependencies such as AS 4.0
+    val json = JsonParser().parse(string).asJsonObject
+    val nodeNamed: JsonObject.(String) -> JsonObject? = { name -> get(name)?.asJsonObject }
+    val valueNamed: JsonObject.(String) -> String? = { name -> get(name)?.asString }
+    val multiObjects: JsonObject.(String?) -> Iterable<JsonObject> = { name -> get(name).asJsonArray.map { it.asJsonObject } }
+    val multiValues: JsonObject.(String?) -> Iterable<String> = { name -> get(name).asJsonArray.map { it.asString } }
+
+    return parseKotlinSourceSetMetadata({ json.get(ROOT_NODE_NAME).asJsonObject }, valueNamed, multiObjects, multiValues)
+}
+
 internal fun parseKotlinSourceSetMetadataFromXml(document: Document): KotlinProjectStructureMetadata? {
-    val projectStructureNode = document.getElementsByTagName(ROOT_NODE_NAME).elements.single()
+    val nodeNamed: Element.(String) -> Element? = { name -> getElementsByTagName(name).elements.singleOrNull() }
+    val valueNamed: Element.(String) -> String? =
+        { name -> getElementsByTagName(name).run { if (length > 0) item(0).textContent else null } }
+    val multiObjects: Element.(String) -> Iterable<Element> = { name -> nodeNamed(name)?.childNodes?.elements ?: emptyList()}
+    val multiValues: Element.(String) -> Iterable<String> = { name -> getElementsByTagName(name).elements.map { it.textContent } }
 
-    val formatVersion = projectStructureNode.getElementsByTagName(FORMAT_VERSION_NODE_NAME).item(0).textContent
+    return parseKotlinSourceSetMetadata(
+        { document.getElementsByTagName(ROOT_NODE_NAME).elements.single() },
+        valueNamed,
+        multiObjects,
+        multiValues
+    )
+}
 
-    val variantsNode = projectStructureNode.getElementsByTagName(VARIANTS_NODE_NAME).item(0) ?: return null
+internal fun <ParsingContext> parseKotlinSourceSetMetadata(
+    getRoot: () -> ParsingContext,
+    valueNamed: ParsingContext.(key: String) -> String?,
+    multiObjects: ParsingContext.(named: String) -> Iterable<ParsingContext>,
+    multiValues: ParsingContext.(named: String) -> Iterable<String>
+): KotlinProjectStructureMetadata? {
+    val projectStructureNode = getRoot()
+
+    val formatVersion = checkNotNull(projectStructureNode.valueNamed(FORMAT_VERSION_NODE_NAME))
+    val variantsNode = projectStructureNode.multiObjects(VARIANTS_NODE_NAME)
 
     val sourceSetsByVariant = mutableMapOf<String, Set<String>>()
 
-    variantsNode.childNodes.elements.filter { it.tagName == VARIANT_NODE_NAME }.forEach { variantNode ->
+    variantsNode.forEach { variantNode ->
-        val variantName = variantNode.getElementsByTagName(NAME_NODE_NAME).elements.single().textContent
+        val variantName = requireNotNull(variantNode.valueNamed(NAME_NODE_NAME))
-        val sourceSets =
+        val sourceSets = variantNode.multiValues(SOURCE_SET_NODE_NAME).toSet()
-            variantNode.childNodes.elements.filter { it.tagName == SOURCE_SET_NODE_NAME }.mapTo(mutableSetOf()) { it.textContent }
 
         sourceSetsByVariant[variantName] = sourceSets
     }
@@ -185,34 +246,24 @@ internal fun parseKotlinSourceSetMetadataFromXml(document: Document): KotlinProj
     val sourceSetBinaryLayout = mutableMapOf<String, SourceSetMetadataLayout>()
     val hostSpecificSourceSets = mutableSetOf<String>()
 
-    val sourceSetsNode = projectStructureNode.getElementsByTagName(SOURCE_SETS_NODE_NAME).item(0) ?: return null
+    val sourceSetsNode = projectStructureNode.multiObjects(SOURCE_SETS_NODE_NAME)
 
-    sourceSetsNode.childNodes.elements.filter { it.tagName == SOURCE_SET_NODE_NAME }.forEach { sourceSetNode ->
+    sourceSetsNode.forEach { sourceSetNode ->
-        val sourceSetName = sourceSetNode.getElementsByTagName(NAME_NODE_NAME).elements.single().textContent
+        val sourceSetName = checkNotNull(sourceSetNode.valueNamed(NAME_NODE_NAME))
 
-        val dependsOn = mutableSetOf<String>()
+        val dependsOn = sourceSetNode.multiValues(DEPENDS_ON_NODE_NAME).toSet()
-        val moduleDependencies = mutableSetOf<ModuleDependencyIdentifier>()
+        val moduleDependencies = sourceSetNode.multiValues(MODULE_DEPENDENCY_NODE_NAME).mapTo(mutableSetOf()) {
-
+            val (groupId, moduleId) = it.split(":")
-        sourceSetNode.childNodes.elements.forEach { node ->
+            ModuleDependencyIdentifier(groupId, moduleId)
-            when (node.tagName) {
-                DEPENDS_ON_NODE_NAME -> dependsOn.add(node.textContent)
-                MODULE_DEPENDENCY_NODE_NAME -> {
-                    val (groupId, moduleId) = node.textContent.split(":")
-                    moduleDependencies.add(ModuleDependencyIdentifier(groupId, moduleId))
-                }
-                BINARY_LAYOUT_NODE_NAME -> {
-                    SourceSetMetadataLayout.byName(node.textContent)?.let { binaryLayout ->
-                        sourceSetBinaryLayout[sourceSetName] = binaryLayout
-                    }
-                }
-                HOST_SPECIFIC_NODE_NAME -> {
-                    if (node.textContent == "true") {
-                        hostSpecificSourceSets.add(sourceSetName)
-                    }
-                }
-            }
         }
 
+        sourceSetNode.valueNamed(HOST_SPECIFIC_NODE_NAME)
+            ?.let { if (it.toBoolean()) hostSpecificSourceSets.add(sourceSetName) }
+
+        sourceSetNode.valueNamed(BINARY_LAYOUT_NODE_NAME)
+            ?.let { SourceSetMetadataLayout.byName(it) }
+            ?.let { sourceSetBinaryLayout[sourceSetName] = it }
+
         sourceSetDependsOnRelation[sourceSetName] = dependsOn
         sourceSetModuleDependencies[sourceSetName] = moduleDependencies
     }

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/metadata/KotlinMetadataTargetConfigurator.kt

@@ -197,7 +197,7 @@ class KotlinMetadataTargetConfigurator(kotlinPluginVersion: String) :
 
         allMetadataJar.configure {
             it.from(generateMetadata.map { it.resultXmlFile }) { spec ->
-                spec.into("META-INF").rename { MULTIPLATFORM_PROJECT_METADATA_FILE_NAME }
+                spec.into("META-INF").rename { MULTIPLATFORM_PROJECT_METADATA_JSON_FILE_NAME }
             }
         }
     }

libraries/tools/kotlin-gradle-plugin/src/test/kotlin/org/jetbrains/kotlin/gradle/internals/ExposedForIntegrationTests.kt

@@ -9,14 +9,13 @@ import org.jetbrains.kotlin.gradle.plugin.KOTLIN_12X_MPP_DEPRECATION_WARNING
 import org.jetbrains.kotlin.gradle.targets.native.internal.NO_NATIVE_STDLIB_PROPERTY_WARNING
 import org.jetbrains.kotlin.gradle.targets.native.internal.NO_NATIVE_STDLIB_WARNING
 import org.jetbrains.kotlin.gradle.plugin.mpp.KotlinProjectStructureMetadata
-import org.jetbrains.kotlin.gradle.plugin.mpp.MULTIPLATFORM_PROJECT_METADATA_FILE_NAME
+import org.jetbrains.kotlin.gradle.plugin.mpp.MULTIPLATFORM_PROJECT_METADATA_JSON_FILE_NAME
-import org.jetbrains.kotlin.gradle.plugin.mpp.parseKotlinSourceSetMetadataFromXml
+import org.jetbrains.kotlin.gradle.plugin.mpp.parseKotlinSourceSetMetadataFromJson
 import org.jetbrains.kotlin.gradle.targets.native.DisabledNativeTargetsReporter
-import org.w3c.dom.Document
 
-fun parseKotlinSourceSetMetadataFromXml(document: Document): KotlinProjectStructureMetadata? = parseKotlinSourceSetMetadataFromXml(document)
+fun parseKotlinSourceSetMetadataFromJson(json: String): KotlinProjectStructureMetadata? = parseKotlinSourceSetMetadataFromJson(json)
 
-const val MULTIPLATFORM_PROJECT_METADATA_FILE_NAME = MULTIPLATFORM_PROJECT_METADATA_FILE_NAME
+const val MULTIPLATFORM_PROJECT_METADATA_JSON_FILE_NAME = MULTIPLATFORM_PROJECT_METADATA_JSON_FILE_NAME
 
 const val DISABLED_NATIVE_TARGETS_REPORTER_DISABLE_WARNING_PROPERTY_NAME = DisabledNativeTargetsReporter.DISABLE_WARNING_PROPERTY_NAME