Add schema-to-html mojo as a replacement for ant ConvertSchemaToHTML

Currently platform build contains ant targets to run ConvertSchemaToHTML
for documentation purpose.

This adds as a first step a new mojo
tycho-document-bundle-plugin:schema-to-html that offers the same
functionality and should act as a base to further improve the brittle
manually maintained references the current process requires and already
allows to move things from the ant build to the maven build files.

(cherry picked from commit 4c276d9)

tycho-extras/tycho-document-bundle-plugin/pom.xml

@@ -9,7 +9,8 @@
 - Contributors:
 -    IBH SYSTEMS GmbH - initial API and implementation
 -->
-<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/maven-v4_0_0.xsd">
 	<modelVersion>4.0.0</modelVersion>
 	<parent>
@@ -60,6 +61,11 @@
 			<artifactId>org.eclipse.help.base</artifactId>
 			<version>4.4.100</version>
 		</dependency>
+		<dependency>
+			<groupId>org.eclipse.pde</groupId>
+			<artifactId>org.eclipse.pde.core</artifactId>
+			<version>3.17.100</version>
+		</dependency>
 	</dependencies>
 	<build>
 		<plugins>

tycho-extras/tycho-document-bundle-plugin/src/main/java/org/eclipse/tycho/extras/docbundle/ConvertSchemaToHtmlMojo.java

@@ -0,0 +1,101 @@
+/*******************************************************************************
+ * Copyright (c) 2023 Christoph Läubrich and others.
+ * This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License 2.0
+ * which accompanies this distribution, and is available at
+ * https://www.eclipse.org/legal/epl-2.0/
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ * Contributors:
+ *     Christoph Läubrich - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.tycho.extras.docbundle;
+
+import java.io.File;
+import java.lang.reflect.InvocationTargetException;
+import java.net.URL;
+import java.util.List;
+
+import org.apache.maven.model.Repository;
+import org.apache.maven.plugin.AbstractMojo;
+import org.apache.maven.plugin.MojoExecutionException;
+import org.apache.maven.plugin.MojoFailureException;
+import org.apache.maven.plugin.logging.Log;
+import org.apache.maven.plugins.annotations.Component;
+import org.apache.maven.plugins.annotations.LifecyclePhase;
+import org.apache.maven.plugins.annotations.Mojo;
+import org.apache.maven.plugins.annotations.Parameter;
+import org.apache.maven.plugins.annotations.ResolutionScope;
+import org.apache.maven.project.MavenProject;
+import org.eclipse.core.runtime.CoreException;
+import org.eclipse.tycho.MavenRepositoryLocation;
+import org.eclipse.tycho.extras.docbundle.runner.ConvertSchemaToHtmlResult;
+import org.eclipse.tycho.extras.docbundle.runner.ConvertSchemaToHtmlRunner;
+import org.eclipse.tycho.osgi.framework.EclipseApplication;
+import org.eclipse.tycho.osgi.framework.EclipseFramework;
+import org.eclipse.tycho.osgi.framework.EclipseWorkspace;
+import org.eclipse.tycho.osgi.framework.EclipseWorkspaceManager;
+import org.osgi.framework.BundleException;
+
+/**
+ * This mojo provides the functionality of
+ * org.eclipse.pde.internal.core.ant.ConvertSchemaToHTML
+ */
+@Mojo(name = "schema-to-html", defaultPhase = LifecyclePhase.PREPARE_PACKAGE, threadSafe = true, requiresDependencyCollection = ResolutionScope.COMPILE_PLUS_RUNTIME)
+public class ConvertSchemaToHtmlMojo extends AbstractMojo {
+
+	@Parameter()
+	private Repository pdeToolsRepository;
+
+	@Parameter()
+	private File manifest;
+	@Parameter()
+	private List<File> manifests;
+	@Parameter()
+	private File destination;
+	@Parameter()
+	private URL cssURL;
+	@Parameter()
+	private String additionalSearchPaths;
+
+	@Parameter(property = "project")
+	private MavenProject project;
+
+	@Component
+	private EclipseWorkspaceManager workspaceManager;
+	@Component
+	private PdeApplicationManager applicationManager;
+
+	@Override
+	public void execute() throws MojoExecutionException, MojoFailureException {
+		MavenRepositoryLocation repository = PdeApplicationManager.getRepository(pdeToolsRepository);
+		EclipseApplication application = applicationManager.getApplication(repository);
+		EclipseWorkspace<?> workspace = workspaceManager.getWorkspace(repository.getURL(), this);
+		try (EclipseFramework framework = application.startFramework(workspace, List.of())) {
+			ConvertSchemaToHtmlResult result = framework.execute(new ConvertSchemaToHtmlRunner(getManifestList(),
+					destination, cssURL, additionalSearchPaths, project.getBasedir()));
+			Log log = getLog();
+			result.errors().forEach(log::error);
+		} catch (BundleException e) {
+			throw new MojoFailureException("Can't start framework!", e);
+		} catch (InvocationTargetException e) {
+			Throwable cause = e.getCause();
+			if (cause.getClass().getName().equals(CoreException.class.getName())) {
+				throw new MojoFailureException(cause.getMessage(), cause);
+			}
+			throw new MojoExecutionException(cause);
+		}
+	}
+
+	private List<File> getManifestList() {
+		if (manifests != null && !manifests.isEmpty()) {
+			return manifests;
+		}
+		if (manifest != null) {
+			return List.of(manifest);
+		}
+		return List.of();
+	}
+
+}

tycho-extras/tycho-document-bundle-plugin/src/main/java/org/eclipse/tycho/extras/docbundle/PdeApplicationManager.java

@@ -0,0 +1,51 @@
+/*******************************************************************************
+ * Copyright (c) 2023 Christoph Läubrich and others.
+ * This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License 2.0
+ * which accompanies this distribution, and is available at
+ * https://www.eclipse.org/legal/epl-2.0/
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ * Contributors:
+ *     Christoph Läubrich - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.tycho.extras.docbundle;
+
+import java.net.URI;
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
+
+import org.apache.maven.model.Repository;
+import org.codehaus.plexus.component.annotations.Component;
+import org.codehaus.plexus.component.annotations.Requirement;
+import org.eclipse.tycho.MavenRepositoryLocation;
+import org.eclipse.tycho.TychoConstants;
+import org.eclipse.tycho.osgi.framework.EclipseApplication;
+import org.eclipse.tycho.osgi.framework.EclipseApplicationFactory;
+
+@Component(role = PdeApplicationManager.class)
+public class PdeApplicationManager {
+
+	static MavenRepositoryLocation getRepository(Repository location) {
+		if (location == null) {
+			return new MavenRepositoryLocation(null, URI.create(TychoConstants.ECLIPSE_LATEST));
+		}
+		return new MavenRepositoryLocation(location.getId(), URI.create(location.getUrl()));
+	}
+
+	private final Map<URI, EclipseApplication> buildIndexCache = new ConcurrentHashMap<>();
+
+	@Requirement
+	private EclipseApplicationFactory applicationFactory;
+
+	public EclipseApplication getApplication(MavenRepositoryLocation repository) {
+		return buildIndexCache.computeIfAbsent(repository.getURL().normalize(), x -> {
+			EclipseApplication application = applicationFactory.createEclipseApplication(repository, "PDE Tools");
+			application.addBundle("org.eclipse.pde.core");
+			application.addBundle("org.eclipse.osgi.compatibility.state");
+			return application;
+		});
+
+	}
+}

tycho-extras/tycho-document-bundle-plugin/src/main/java/org/eclipse/tycho/extras/docbundle/runner/ConvertSchemaToHtmlResult.java

@@ -0,0 +1,32 @@
+/*******************************************************************************
+ * Copyright (c) 2023 Christoph Läubrich and others.
+ * This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License 2.0
+ * which accompanies this distribution, and is available at
+ * https://www.eclipse.org/legal/epl-2.0/
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ * Contributors:
+ *     Christoph Läubrich - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.tycho.extras.docbundle.runner;
+
+import java.io.Serializable;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.stream.Stream;
+
+public class ConvertSchemaToHtmlResult implements Serializable {
+
+	private List<String> errors = new ArrayList<>();
+
+	public void addError(String error) {
+		errors.add(error);
+	}
+
+	public Stream<String> errors() {
+		return errors.stream();
+	}
+
+}