Improve aggregation in the reference docs project

Closes gh-46600

buildSrc/build.gradle

@@ -84,6 +84,10 @@ configurations.all {
 
 gradlePlugin {
 	plugins {
+		aggregatorPlugin {
+			id = "org.springframework.boot.aggregator"
+			implementationClass = "org.springframework.boot.build.aggregation.AggregatorPlugin"
+		}
 		annotationProcessorPlugin {
 			id = "org.springframework.boot.annotation-processor"
 			implementationClass = "org.springframework.boot.build.processors.AnnotationProcessorPlugin"

buildSrc/src/main/java/org/springframework/boot/build/aggregation/Aggregate.java

@@ -0,0 +1,50 @@
+/*
+ * Copyright 2012-present the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.boot.build.aggregation;
+
+import org.gradle.api.Named;
+import org.gradle.api.attributes.Category;
+import org.gradle.api.attributes.Usage;
+import org.gradle.api.file.ConfigurableFileCollection;
+import org.gradle.api.provider.Property;
+
+/**
+ * An aggregate.
+ *
+ * @author Andy Wilkinson
+ */
+public interface Aggregate extends Named {
+
+	/**
+	 * The {@link Category} used to select the variant that's included in the aggregate.
+	 * @return the category
+	 */
+	Property<String> getCategory();
+
+	/**
+	 * The {@link Usage} used to select the variant that's included in the aggregate.
+	 * @return the usage
+	 */
+	Property<String> getUsage();
+
+	/**
+	 * The aggregated files.
+	 * @return the aggregated files
+	 */
+	ConfigurableFileCollection getFiles();
+
+}

buildSrc/src/main/java/org/springframework/boot/build/aggregation/AggregatorPlugin.java

@@ -0,0 +1,69 @@
+/*
+ * Copyright 2012-present the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.boot.build.aggregation;
+
+import org.gradle.api.NamedDomainObjectContainer;
+import org.gradle.api.NamedDomainObjectProvider;
+import org.gradle.api.Plugin;
+import org.gradle.api.Project;
+import org.gradle.api.artifacts.Configuration;
+import org.gradle.api.artifacts.DependencyScopeConfiguration;
+import org.gradle.api.artifacts.ResolvableConfiguration;
+import org.gradle.api.attributes.Category;
+import org.gradle.api.attributes.Usage;
+import org.gradle.api.model.ObjectFactory;
+
+/**
+ * {@link Plugin} for aggregating the output of other projects.
+ *
+ * @author Andy Wilkinson
+ */
+public class AggregatorPlugin implements Plugin<Project> {
+
+	@Override
+	public void apply(Project target) {
+		NamedDomainObjectContainer<Aggregate> aggregates = target.getObjects().domainObjectContainer(Aggregate.class);
+		target.getExtensions().add("aggregates", aggregates);
+		aggregates.all((aggregate) -> {
+			NamedDomainObjectProvider<DependencyScopeConfiguration> dependencies = target.getConfigurations()
+				.dependencyScope(aggregate.getName() + "Dependencies",
+						(configuration) -> configureAttributes(configuration, aggregate, target.getObjects()));
+			NamedDomainObjectProvider<ResolvableConfiguration> aggregated = target.getConfigurations()
+				.resolvable(aggregate.getName(), (configuration) -> {
+					configuration.extendsFrom(dependencies.get());
+					configureAttributes(configuration, aggregate, target.getObjects());
+				});
+			target.getRootProject()
+				.allprojects((project) -> target.getDependencies().add(dependencies.getName(), project));
+			aggregate.getFiles()
+				.convention(aggregated.map((configuration) -> configuration.getIncoming()
+					.artifactView((view) -> view.setLenient(true))
+					.getFiles()));
+		});
+	}
+
+	private void configureAttributes(Configuration configuration, Aggregate aggregate, ObjectFactory objects) {
+		configuration.attributes((attributes) -> {
+			attributes.attributeProvider(Category.CATEGORY_ATTRIBUTE,
+					aggregate.getCategory().map((category) -> objects.named(Category.class, category)));
+			attributes.attributeProvider(Usage.USAGE_ATTRIBUTE,
+					aggregate.getUsage().map((usage) -> objects.named(Usage.class, usage)));
+		});
+
+	}
+
+}

buildSrc/src/main/java/org/springframework/boot/build/autoconfigure/AutoConfigurationMetadata.java

@@ -61,8 +61,6 @@ public abstract class AutoConfigurationMetadata extends DefaultTask {
 	private FileCollection classesDirectories;
 
 	public AutoConfigurationMetadata() {
-		getProject().getConfigurations()
-			.maybeCreate(AutoConfigurationPlugin.AUTO_CONFIGURATION_METADATA_CONFIGURATION_NAME);
 		this.moduleName = getProject().getName();
 	}
 

buildSrc/src/main/java/org/springframework/boot/build/autoconfigure/AutoConfigurationPlugin.java

@@ -26,6 +26,8 @@ import org.gradle.api.Project;
 import org.gradle.api.artifacts.Configuration;
 import org.gradle.api.artifacts.ConfigurationContainer;
 import org.gradle.api.artifacts.Dependency;
+import org.gradle.api.attributes.Category;
+import org.gradle.api.attributes.Usage;
 import org.gradle.api.plugins.JavaBasePlugin;
 import org.gradle.api.plugins.JavaPlugin;
 import org.gradle.api.plugins.JavaPluginExtension;
@@ -53,11 +55,7 @@ import org.springframework.boot.build.optional.OptionalDependenciesPlugin;
  */
 public class AutoConfigurationPlugin implements Plugin<Project> {
 
-	/**
+	private static final String AUTO_CONFIGURATION_METADATA_CONFIGURATION_NAME = "autoConfigurationMetadata";
-	 * Name of the {@link Configuration} that holds the auto-configuration metadata
-	 * artifact.
-	 */
-	public static final String AUTO_CONFIGURATION_METADATA_CONFIGURATION_NAME = "autoConfigurationMetadata";
 
 	@Override
 	public void apply(Project project) {
@@ -83,6 +81,14 @@ public class AutoConfigurationPlugin implements Plugin<Project> {
 			addAnnotationProcessorsDependencies();
 			TaskContainer tasks = this.project.getTasks();
 			ConfigurationContainer configurations = this.project.getConfigurations();
+			configurations.consumable(AUTO_CONFIGURATION_METADATA_CONFIGURATION_NAME, (configuration) -> {
+				configuration.attributes((attributes) -> {
+					attributes.attribute(Category.CATEGORY_ATTRIBUTE,
+							this.project.getObjects().named(Category.class, Category.DOCUMENTATION));
+					attributes.attribute(Usage.USAGE_ATTRIBUTE,
+							this.project.getObjects().named(Usage.class, "auto-configuration-metadata"));
+				});
+			});
 			tasks.register("autoConfigurationMetadata", AutoConfigurationMetadata.class,
 					this::configureAutoConfigurationMetadata);
 			TaskProvider<CheckAutoConfigurationImports> checkAutoConfigurationImports = tasks.register(

buildSrc/src/main/java/org/springframework/boot/build/autoconfigure/DocumentAutoConfigurationClasses.java

@@ -36,6 +36,8 @@ import org.gradle.api.file.DirectoryProperty;
 import org.gradle.api.file.FileCollection;
 import org.gradle.api.tasks.InputFiles;
 import org.gradle.api.tasks.OutputDirectory;
+import org.gradle.api.tasks.PathSensitive;
+import org.gradle.api.tasks.PathSensitivity;
 import org.gradle.api.tasks.TaskAction;
 
 import org.springframework.util.StringUtils;
@@ -50,6 +52,7 @@ public abstract class DocumentAutoConfigurationClasses extends DefaultTask {
 	private FileCollection autoConfiguration;
 
 	@InputFiles
+	@PathSensitive(PathSensitivity.RELATIVE)
 	public FileCollection getAutoConfiguration() {
 		return this.autoConfiguration;
 	}

buildSrc/src/main/java/org/springframework/boot/build/context/properties/ConfigurationPropertiesPlugin.java

@@ -23,6 +23,8 @@ import org.gradle.api.Plugin;
 import org.gradle.api.Project;
 import org.gradle.api.Task;
 import org.gradle.api.artifacts.Configuration;
+import org.gradle.api.attributes.Category;
+import org.gradle.api.attributes.Usage;
 import org.gradle.api.file.RegularFile;
 import org.gradle.api.plugins.JavaPlugin;
 import org.gradle.api.plugins.JavaPluginExtension;
@@ -56,11 +58,7 @@ import org.springframework.util.StringUtils;
  */
 public class ConfigurationPropertiesPlugin implements Plugin<Project> {
 
-	/**
+	private static final String CONFIGURATION_PROPERTIES_METADATA_CONFIGURATION_NAME = "configurationPropertiesMetadata";
-	 * Name of the {@link Configuration} that holds the configuration property metadata
-	 * artifact.
-	 */
-	public static final String CONFIGURATION_PROPERTIES_METADATA_CONFIGURATION_NAME = "configurationPropertiesMetadata";
 
 	/**
 	 * Name of the {@link CheckAdditionalSpringConfigurationMetadata} task.
@@ -108,7 +106,15 @@ public class ConfigurationPropertiesPlugin implements Plugin<Project> {
 			.getByType(JavaPluginExtension.class)
 			.getSourceSets()
 			.getByName(SourceSet.MAIN_SOURCE_SET_NAME);
-		project.getConfigurations().maybeCreate(CONFIGURATION_PROPERTIES_METADATA_CONFIGURATION_NAME);
+		project.getConfigurations()
+			.consumable(CONFIGURATION_PROPERTIES_METADATA_CONFIGURATION_NAME, (configuration) -> {
+				configuration.attributes((attributes) -> {
+					attributes.attribute(Category.CATEGORY_ATTRIBUTE,
+							project.getObjects().named(Category.class, Category.DOCUMENTATION));
+					attributes.attribute(Usage.USAGE_ATTRIBUTE,
+							project.getObjects().named(Usage.class, "configuration-properties-metadata"));
+				});
+			});
 		project.afterEvaluate((evaluatedProject) -> evaluatedProject.getArtifacts()
 			.add(CONFIGURATION_PROPERTIES_METADATA_CONFIGURATION_NAME,
 					mainSourceSet.getJava()

spring-boot-project/spring-boot-docs/build.gradle

@@ -20,17 +20,16 @@ plugins {
 	id "dev.adamko.dokkatoo-html"
 	id "java"
 	id "org.antora"
+	id "org.jetbrains.kotlin.jvm"
+	id "org.springframework.boot.aggregator"
 	id "org.springframework.boot.antora-contributor"
 	id "org.springframework.boot.antora-dependencies"
 	id "org.springframework.boot.deployed"
-	id 'org.jetbrains.kotlin.jvm'
 }
 
 description = "Spring Boot Docs"
 
 configurations {
-	autoConfiguration
-	configurationProperties
 	remoteSpringApplicationExample
 	resolvedBom
 	springApplicationExample
@@ -69,20 +68,6 @@ plugins.withType(EclipsePlugin) {
 }
 
 dependencies {
-	autoConfiguration(project(path: ":spring-boot-project:spring-boot-actuator-autoconfigure", configuration: "autoConfigurationMetadata"))
-	autoConfiguration(project(path: ":spring-boot-project:spring-boot-autoconfigure", configuration: "autoConfigurationMetadata"))
-	autoConfiguration(project(path: ":spring-boot-project:spring-boot-devtools", configuration: "autoConfigurationMetadata"))
-	autoConfiguration(project(path: ":spring-boot-project:spring-boot-testcontainers", configuration: "autoConfigurationMetadata"))
-
-	configurationProperties(project(path: ":spring-boot-project:spring-boot", configuration: "configurationPropertiesMetadata"))
-	configurationProperties(project(path: ":spring-boot-project:spring-boot-actuator", configuration: "configurationPropertiesMetadata"))
-	configurationProperties(project(path: ":spring-boot-project:spring-boot-actuator-autoconfigure", configuration: "configurationPropertiesMetadata"))
-	configurationProperties(project(path: ":spring-boot-project:spring-boot-autoconfigure", configuration: "configurationPropertiesMetadata"))
-	configurationProperties(project(path: ":spring-boot-project:spring-boot-devtools", configuration: "configurationPropertiesMetadata"))
-	configurationProperties(project(path: ":spring-boot-project:spring-boot-docker-compose", configuration: "configurationPropertiesMetadata"))
-	configurationProperties(project(path: ":spring-boot-project:spring-boot-test-autoconfigure", configuration: "configurationPropertiesMetadata"))
-	configurationProperties(project(path: ":spring-boot-project:spring-boot-testcontainers", configuration: "configurationPropertiesMetadata"))
-
 	dokkatoo(project(path: ":spring-boot-project:spring-boot"))
 	dokkatoo(project(path: ":spring-boot-project:spring-boot-test"))
 
@@ -257,8 +242,13 @@ tasks.register("documentStarters", org.springframework.boot.build.starters.Docum
 	outputDir = layout.buildDirectory.dir("generated/docs/using/starters/")
 }
 
+def autoConfigurationMetadataAggregate = aggregates.create("autoConfigurationMetadata") {
+	category = Category.DOCUMENTATION
+	usage = "auto-configuration-metadata"
+}
+
 tasks.register("documentAutoConfigurationClasses", org.springframework.boot.build.autoconfigure.DocumentAutoConfigurationClasses) {
-	autoConfiguration = configurations.autoConfiguration
+	autoConfiguration = autoConfigurationMetadataAggregate.files
 	outputDir = layout.buildDirectory.dir("generated/docs/auto-configuration-classes/documented-auto-configuration-classes/")
 }
 
@@ -272,8 +262,13 @@ tasks.register("documentDependencyVersionProperties", org.springframework.boot.b
 	resolvedBoms = configurations.resolvedBom
 }
 
+def configurationPropertiesMetadataAggregate = aggregates.create("configurationPropertiesMetadata") {
+	category = Category.DOCUMENTATION
+	usage = "configuration-properties-metadata"
+}
+
 tasks.register("documentConfigurationProperties", org.springframework.boot.build.context.properties.DocumentConfigurationProperties) {
-	configurationPropertyMetadata = configurations.configurationProperties
+	configurationPropertyMetadata = configurationPropertiesMetadataAggregate.files
 	outputDir = layout.buildDirectory.dir("generated/docs/application-properties")
 }
 
@@ -349,7 +344,7 @@ antoraContributions {
 			from("src/main") {
 				into "modules/ROOT/examples"
 			}
-			from(project.configurations.configurationProperties) {
+			from(configurationPropertiesMetadataAggregate.files) {
 				eachFile {
 					it.path = rootProject
 						.projectDir