[Gradle] Some tweaks to transport related build logic

build-tools-internal/src/main/java/org/elasticsearch/gradle/internal/ProjectSubscribeBuildService.java

@@ -0,0 +1,51 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the "Elastic License
+ * 2.0", the "GNU Affero General Public License v3.0 only", and the "Server Side
+ * Public License v 1"; you may not use this file except in compliance with, at
+ * your election, the "Elastic License 2.0", the "GNU Affero General Public
+ * License v3.0 only", or the "Server Side Public License, v 1".
+ */
+
+package org.elasticsearch.gradle.internal;
+
+import org.gradle.api.Project;
+import org.gradle.api.provider.Provider;
+import org.gradle.api.provider.ProviderFactory;
+import org.gradle.api.services.BuildService;
+import org.gradle.api.services.BuildServiceParameters;
+
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.Map;
+
+import javax.inject.Inject;
+
+public abstract class ProjectSubscribeBuildService implements BuildService<BuildServiceParameters.None> {
+
+    private final ProviderFactory providerFactory;
+
+    /**
+     * The filling of this map depends on the order of #registerProjectForTopic being called.
+     * This is usually done during configuration phase, but we do not enforce yet the time of this method call.
+     * The values are LinkedHashSet to preserve the order of registration mostly to provide a predicatable order
+     * when running consecutive builds.
+     * */
+    private final Map<String, Collection<String>> versionsByTopic = new HashMap<>();
+
+    @Inject
+    public ProjectSubscribeBuildService(ProviderFactory providerFactory) {
+        this.providerFactory = providerFactory;
+    }
+
+    /**
+     * Returning a provider so the evaluation of the map value is deferred to when the provider is queried.
+     * */
+    public Provider<Collection<String>> getProjectsByTopic(String topic) {
+        return providerFactory.provider(() -> versionsByTopic.computeIfAbsent(topic, k -> new java.util.LinkedHashSet<>()));
+    }
+
+    public void registerProjectForTopic(String topic, Project project) {
+        versionsByTopic.computeIfAbsent(topic, k -> new java.util.LinkedHashSet<>()).add(project.getPath());
+    }
+}

build-tools-internal/src/main/java/org/elasticsearch/gradle/internal/ProjectSubscribeServicePlugin.java

@@ -0,0 +1,44 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the "Elastic License
+ * 2.0", the "GNU Affero General Public License v3.0 only", and the "Server Side
+ * Public License v 1"; you may not use this file except in compliance with, at
+ * your election, the "Elastic License 2.0", the "GNU Affero General Public
+ * License v3.0 only", or the "Server Side Public License, v 1".
+ */
+
+package org.elasticsearch.gradle.internal;
+
+import org.gradle.api.Plugin;
+import org.gradle.api.Project;
+import org.gradle.api.provider.Provider;
+
+/**
+ * This plugin registers a {@link ProjectSubscribeBuildService} to allow projects to
+ * communicate with each other during the configuration phase.
+ *
+ * For example, a project can register itself as a publisher of a topic, and other
+ * projects can resolve projects that have registered as publishers of that topic.
+ *
+ * The actual resolution of whatever data is usually done using dependency declarations.
+ * Be aware the state of the list depends on the order of project configuration and
+ * consuming on configuration phase before task graph calculation phase should be avoided.
+ *
+ * We want to avoid discouraged plugin api usage like project.allprojects or project.subprojects
+ * in plugins to avoid unnecessary configuration of projects and not break project isolation and break
+ * See https://docs.gradle.org/current/userguide/isolated_projects.html
+ * */
+public class ProjectSubscribeServicePlugin implements Plugin<Project> {
+
+    private Provider<ProjectSubscribeBuildService> publishSubscribe;
+
+    @Override
+    public void apply(Project project) {
+        publishSubscribe = project.getGradle().getSharedServices().registerIfAbsent("publishSubscribe", ProjectSubscribeBuildService.class);
+    }
+
+    public Provider<ProjectSubscribeBuildService> getService() {
+        return publishSubscribe;
+    }
+
+}

build-tools-internal/src/main/java/org/elasticsearch/gradle/internal/transport/GenerateTransportVersionManifestTask.java

@@ -44,7 +44,6 @@ public Path getDefinitionsDirectory() {
 
     @TaskAction
     public void generateTransportVersionManifest() throws IOException {
-
         Path definitionsDir = getDefinitionsDirectory();
         Path manifestFile = getManifestFile().get().getAsFile().toPath();
         try (var writer = Files.newBufferedWriter(manifestFile)) {

build-tools-internal/src/main/java/org/elasticsearch/gradle/internal/transport/TransportVersionReferencesPlugin.java

@@ -9,19 +9,27 @@
 
 package org.elasticsearch.gradle.internal.transport;
 
+import org.elasticsearch.gradle.internal.ProjectSubscribeServicePlugin;
 import org.elasticsearch.gradle.util.GradleUtils;
 import org.gradle.api.Plugin;
 import org.gradle.api.Project;
-import org.gradle.api.artifacts.Configuration;
 import org.gradle.api.tasks.SourceSet;
 import org.gradle.language.base.plugins.LifecycleBasePlugin;
 
+import static org.elasticsearch.gradle.internal.transport.TransportVersionResourcesPlugin.TRANSPORT_REFERENCES_TOPIC;
+
 public class TransportVersionReferencesPlugin implements Plugin<Project> {
 
     @Override
     public void apply(Project project) {
         project.getPluginManager().apply(LifecycleBasePlugin.class);
 
+        project.getPlugins()
+            .apply(ProjectSubscribeServicePlugin.class)
+            .getService()
+            .get()
+            .registerProjectForTopic(TRANSPORT_REFERENCES_TOPIC, project);
+
         var collectTask = project.getTasks()
             .register("collectTransportVersionReferences", CollectTransportVersionReferencesTask.class, t -> {
                 t.setGroup("Transport Versions");
@@ -31,9 +39,7 @@ public void apply(Project project) {
                 t.getOutputFile().set(project.getLayout().getBuildDirectory().file("transport-version/references.txt"));
             });
 
-        Configuration tvReferencesConfig = project.getConfigurations().create("transportVersionReferences", c -> {
-            c.setCanBeConsumed(true);
-            c.setCanBeResolved(false);
+        var tvReferencesConfig = project.getConfigurations().consumable("transportVersionReferences", c -> {
             c.attributes(TransportVersionReference::addArtifactAttribute);
         });
         project.getArtifacts().add(tvReferencesConfig.getName(), collectTask);

build-tools-internal/src/main/java/org/elasticsearch/gradle/internal/transport/TransportVersionResourcesPlugin.java

@@ -9,10 +9,9 @@
 
 package org.elasticsearch.gradle.internal.transport;
 
+import org.elasticsearch.gradle.internal.ProjectSubscribeServicePlugin;
 import org.gradle.api.Plugin;
 import org.gradle.api.Project;
-import org.gradle.api.artifacts.Configuration;
-import org.gradle.api.artifacts.dsl.DependencyHandler;
 import org.gradle.api.file.Directory;
 import org.gradle.api.plugins.JavaPlugin;
 import org.gradle.api.tasks.Copy;
@@ -22,32 +21,33 @@
 
 public class TransportVersionResourcesPlugin implements Plugin<Project> {
 
+    public static final String TRANSPORT_REFERENCES_TOPIC = "transportReferences";
+
     @Override
     public void apply(Project project) {
         project.getPluginManager().apply(LifecycleBasePlugin.class);
-
-        String resourceRoot = getResourceRoot(project);
+        var psService = project.getPlugins().apply(ProjectSubscribeServicePlugin.class).getService();
+        var resourceRoot = getResourceRoot(project);
 
         project.getGradle()
             .getSharedServices()
             .registerIfAbsent("transportVersionResources", TransportVersionResourcesService.class, spec -> {
                 Directory transportResources = project.getLayout().getProjectDirectory().dir("src/main/resources/" + resourceRoot);
                 spec.getParameters().getTransportResourcesDirectory().set(transportResources);
-                spec.getParameters().getRootDirectory().set(project.getRootProject().getRootDir());
+                spec.getParameters().getRootDirectory().set(project.getLayout().getSettingsDirectory().getAsFile());
             });
 
-        DependencyHandler depsHandler = project.getDependencies();
-        Configuration tvReferencesConfig = project.getConfigurations().create("globalTvReferences");
-        tvReferencesConfig.setCanBeConsumed(false);
-        tvReferencesConfig.setCanBeResolved(true);
-        tvReferencesConfig.attributes(TransportVersionReference::addArtifactAttribute);
-
-        // iterate through all projects, and if the management plugin is applied, add that project back as a dep to check
-        for (Project subProject : project.getRootProject().getSubprojects()) {
-            subProject.getPlugins().withType(TransportVersionReferencesPlugin.class).configureEach(plugin -> {
-                tvReferencesConfig.getDependencies().add(depsHandler.project(Map.of("path", subProject.getPath())));
-            });
-        }
+        var depsHandler = project.getDependencies();
+        var tvReferencesConfig = project.getConfigurations().create("globalTvReferences", c -> {
+            c.setCanBeConsumed(false);
+            c.setCanBeResolved(true);
+            c.attributes(TransportVersionReference::addArtifactAttribute);
+            c.getDependencies()
+                .addAllLater(
+                    psService.flatMap(t -> t.getProjectsByTopic(TRANSPORT_REFERENCES_TOPIC))
+                        .map(projectPaths -> projectPaths.stream().map(path -> depsHandler.project(Map.of("path", path))).toList())
+                );
+        });
 
         var validateTask = project.getTasks()
             .register("validateTransportVersionResources", ValidateTransportVersionResourcesTask.class, t -> {

build-tools-internal/src/main/java/org/elasticsearch/gradle/internal/transport/ValidateTransportVersionReferencesTask.java

@@ -20,6 +20,8 @@
 import org.gradle.api.tasks.PathSensitive;
 import org.gradle.api.tasks.PathSensitivity;
 import org.gradle.api.tasks.TaskAction;
+import org.gradle.api.tasks.VerificationException;
+import org.gradle.api.tasks.VerificationTask;
 
 import java.io.IOException;
 import java.nio.file.Path;
@@ -28,7 +30,7 @@
  * Validates that each transport version reference has a referable definition.
  */
 @CacheableTask
-public abstract class ValidateTransportVersionReferencesTask extends DefaultTask {
+public abstract class ValidateTransportVersionReferencesTask extends DefaultTask implements VerificationTask {
 
     @ServiceReference("transportVersionResources")
     abstract Property<TransportVersionResourcesService> getTransportResources();
@@ -51,7 +53,7 @@ public void validateTransportVersions() throws IOException {
 
         for (var tvReference : TransportVersionReference.listFromFile(namesFile)) {
             if (resources.referableDefinitionExists(tvReference.name()) == false) {
-                throw new RuntimeException(
+                throw new VerificationException(
                     "TransportVersion.fromName(\""
                         + tvReference.name()
                         + "\") was used at "

build-tools-internal/src/main/java/org/elasticsearch/gradle/internal/transport/ValidateTransportVersionResourcesTask.java

@@ -22,6 +22,8 @@
 import org.gradle.api.tasks.PathSensitive;
 import org.gradle.api.tasks.PathSensitivity;
 import org.gradle.api.tasks.TaskAction;
+import org.gradle.api.tasks.VerificationException;
+import org.gradle.api.tasks.VerificationTask;
 
 import java.io.IOException;
 import java.nio.file.Path;
@@ -38,7 +40,7 @@
  * Validates that each defined transport version constant is referenced by at least one project.
  */
 @CacheableTask
-public abstract class ValidateTransportVersionResourcesTask extends DefaultTask {
+public abstract class ValidateTransportVersionResourcesTask extends DefaultTask implements VerificationTask {
 
     @InputDirectory
     @Optional
@@ -255,11 +257,11 @@ private void validateBase(int base, List<IdAndDefinition> ids) {
 
     private void throwDefinitionFailure(TransportVersionDefinition definition, String message) {
         Path relativePath = getResources().get().getReferableDefinitionRepositoryPath(definition);
-        throw new IllegalStateException("Transport version definition file [" + relativePath + "] " + message);
+        throw new VerificationException("Transport version definition file [" + relativePath + "] " + message);
     }
 
     private void throwUpperBoundFailure(TransportVersionUpperBound upperBound, String message) {
         Path relativePath = getResources().get().getUpperBoundRepositoryPath(upperBound);
-        throw new IllegalStateException("Transport version upper bound file [" + relativePath + "] " + message);
+        throw new VerificationException("Transport version upper bound file [" + relativePath + "] " + message);
     }
 }