Merge pull request #31126 from abel533

* pr/31126:
  Polish "Resolve errors in layers.xsd"
  Resolve errors in layers.xsd

Closes gh-31126

spring-boot-project/spring-boot-tools/spring-boot-maven-plugin/build.gradle

@@ -64,6 +64,11 @@ dependencies {
 	versionProperties(project(path: ":spring-boot-project:spring-boot-dependencies", configuration: "effectiveBom"))
 }
 
+ext {
+	versionElements = version.split("\\.")
+	xsdVersion = versionElements[0] + "." + versionElements[1]
+}
+
 syncDocumentationSourceForAsciidoctor {
 	from(documentPluginGoals) {
 		into "asciidoc/goals"
@@ -71,6 +76,9 @@ syncDocumentationSourceForAsciidoctor {
 }
 
 sourceSets {
+	main {
+		output.dir("${buildDir}/generated/resources/xsd", builtBy: "xsdResources")
+	}
 	intTest {
 		output.dir("${buildDir}/generated-resources", builtBy: "extractVersionProperties")
 	}
@@ -78,8 +86,7 @@ sourceSets {
 
 tasks.withType(org.asciidoctor.gradle.jvm.AbstractAsciidoctorTask) {
 	doFirst {
-		def versionEl = version.split("\\.")
+		attributes "spring-boot-xsd-version" : project.ext.xsdVersion
-		attributes "spring-boot-xsd-version": versionEl[0] + '.' + versionEl[1]
 	}
 }
 
@@ -129,6 +136,12 @@ task zip(type: Zip) {
 	}
 }
 
+task xsdResources(type: Sync) {
+	from "src/main/xsd/layers-${project.ext.xsdVersion}.xsd"
+	into "${buildDir}/generated/resources/xsd/org/springframework/boot/maven"
+	rename { fileName -> "layers.xsd" }
+}
+
 prepareMavenBinaries {
 	versions "3.8.1", "3.6.3", "3.5.4"
 }

spring-boot-project/spring-boot-tools/spring-boot-maven-plugin/src/main/java/org/springframework/boot/maven/AbstractPackagerMojo.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2021 the original author or authors.
+ * Copyright 2012-2022 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.
@@ -171,6 +171,7 @@ public abstract class AbstractPackagerMojo extends AbstractDependencyFilterMojo
 	private Document getDocumentIfAvailable(File xmlFile) throws Exception {
 		InputSource inputSource = new InputSource(new FileInputStream(xmlFile));
 		DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
+		factory.setNamespaceAware(true);
 		DocumentBuilder builder = factory.newDocumentBuilder();
 		return builder.parse(inputSource);
 	}

spring-boot-project/spring-boot-tools/spring-boot-maven-plugin/src/main/java/org/springframework/boot/maven/CustomLayersProvider.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2020 the original author or authors.
+ * Copyright 2012-2022 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.
@@ -16,16 +16,24 @@
 
 package org.springframework.boot.maven;
 
+import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
 import java.util.function.Function;
 import java.util.stream.Collectors;
 
+import javax.xml.XMLConstants;
+import javax.xml.transform.dom.DOMSource;
+import javax.xml.validation.Schema;
+import javax.xml.validation.SchemaFactory;
+import javax.xml.validation.Validator;
+
 import org.w3c.dom.Document;
 import org.w3c.dom.Element;
 import org.w3c.dom.Node;
 import org.w3c.dom.NodeList;
+import org.xml.sax.SAXException;
 
 import org.springframework.boot.loader.tools.Layer;
 import org.springframework.boot.loader.tools.Library;
@@ -45,6 +53,7 @@ import org.springframework.boot.loader.tools.layer.LibraryContentFilter;
 class CustomLayersProvider {
 
 	CustomLayers getLayers(Document document) {
+		validate(document);
 		Element root = document.getDocumentElement();
 		List<ContentSelector<String>> applicationSelectors = getApplicationSelectors(root);
 		List<ContentSelector<Library>> librarySelectors = getLibrarySelectors(root);
@@ -52,6 +61,27 @@ class CustomLayersProvider {
 		return new CustomLayers(layers, applicationSelectors, librarySelectors);
 	}
 
+	private void validate(Document document) {
+		Schema schema = loadSchema();
+		try {
+			Validator validator = schema.newValidator();
+			validator.validate(new DOMSource(document));
+		}
+		catch (SAXException | IOException ex) {
+			throw new IllegalStateException("Invalid layers.xml configuration", ex);
+		}
+	}
+
+	private Schema loadSchema() {
+		try {
+			SchemaFactory factory = SchemaFactory.newInstance(XMLConstants.W3C_XML_SCHEMA_NS_URI);
+			return factory.newSchema(getClass().getResource("layers.xsd"));
+		}
+		catch (SAXException ex) {
+			throw new IllegalStateException("Unable to load layers XSD");
+		}
+	}
+
 	private List<ContentSelector<String>> getApplicationSelectors(Element root) {
 		return getSelectors(root, "application", (element) -> getSelector(element, ApplicationContentFilter::new));
 	}

spring-boot-project/spring-boot-tools/spring-boot-maven-plugin/src/main/xsd/layers-2.3.xsd

@@ -6,9 +6,9 @@
 	<xsd:element name="layers" type="layersType" />
 	<xsd:complexType name="layersType">
 		<xsd:sequence>
-			<xsd:element name="application" type="applicationType" />
+			<xsd:element name="application" type="applicationType" minOccurs="0"/>
-			<xsd:element name="dependencies" type="dependenciesType" />
+			<xsd:element name="dependencies" type="dependenciesType" minOccurs="0"/>
-			<xsd:element name="layerOrder" type="layerOrderType" />
+			<xsd:element name="layerOrder" type="layerOrderType" minOccurs="0"/>
 		</xsd:sequence>
 	</xsd:complexType>
 	<xsd:complexType name="applicationType">

spring-boot-project/spring-boot-tools/spring-boot-maven-plugin/src/main/xsd/layers-2.4.xsd

@@ -6,9 +6,9 @@
 	<xsd:element name="layers" type="layersType" />
 	<xsd:complexType name="layersType">
 		<xsd:sequence>
-			<xsd:element name="application" type="applicationType" />
+			<xsd:element name="application" type="applicationType" minOccurs="0"/>
-			<xsd:element name="dependencies" type="dependenciesType" />
+			<xsd:element name="dependencies" type="dependenciesType" minOccurs="0"/>
-			<xsd:element name="layerOrder" type="layerOrderType" />
+			<xsd:element name="layerOrder" type="layerOrderType" minOccurs="0"/>
 		</xsd:sequence>
 	</xsd:complexType>
 	<xsd:complexType name="applicationType">
@@ -78,21 +78,21 @@
 		<xsd:complexContent>
 			<xsd:extension base="intoType">
 				<xsd:choice minOccurs="0">
-					<xsd:element type="xsd:string" name="includeProjectDependencies" minOccurs="0">
+					<xsd:element type="xsd:string" name="includeModuleDependencies" minOccurs="0">
 						<xsd:annotation>
 							<xsd:documentation><![CDATA[
 	Include dependencies on other modules in the build.
 							]]></xsd:documentation>
 						</xsd:annotation>
 					</xsd:element>
-					<xsd:element type="xsd:string" name="excludeProjectDependencies" minOccurs="0">
+					<xsd:element type="xsd:string" name="excludeModuleDependencies" minOccurs="0">
 						<xsd:annotation>
 							<xsd:documentation><![CDATA[
 	Exclude dependencies on other modules in the build.
 							]]></xsd:documentation>
 						</xsd:annotation>
 					</xsd:element>
-				</xsd:choice>				
+				</xsd:choice>
 			</xsd:extension>
 		</xsd:complexContent>
 	</xsd:complexType>

spring-boot-project/spring-boot-tools/spring-boot-maven-plugin/src/main/xsd/layers-2.5.xsd

@@ -6,9 +6,9 @@
 	<xsd:element name="layers" type="layersType" />
 	<xsd:complexType name="layersType">
 		<xsd:sequence>
-			<xsd:element name="application" type="applicationType" />
+			<xsd:element name="application" type="applicationType" minOccurs="0"/>
-			<xsd:element name="dependencies" type="dependenciesType" />
+			<xsd:element name="dependencies" type="dependenciesType" minOccurs="0"/>
-			<xsd:element name="layerOrder" type="layerOrderType" />
+			<xsd:element name="layerOrder" type="layerOrderType" minOccurs="0"/>
 		</xsd:sequence>
 	</xsd:complexType>
 	<xsd:complexType name="applicationType">
@@ -78,21 +78,21 @@
 		<xsd:complexContent>
 			<xsd:extension base="intoType">
 				<xsd:choice minOccurs="0">
-					<xsd:element type="xsd:string" name="includeProjectDependencies" minOccurs="0">
+					<xsd:element type="xsd:string" name="includeModuleDependencies" minOccurs="0">
 						<xsd:annotation>
 							<xsd:documentation><![CDATA[
 	Include dependencies on other modules in the build.
 							]]></xsd:documentation>
 						</xsd:annotation>
 					</xsd:element>
-					<xsd:element type="xsd:string" name="excludeProjectDependencies" minOccurs="0">
+					<xsd:element type="xsd:string" name="excludeModuleDependencies" minOccurs="0">
 						<xsd:annotation>
 							<xsd:documentation><![CDATA[
 	Exclude dependencies on other modules in the build.
 							]]></xsd:documentation>
 						</xsd:annotation>
 					</xsd:element>
-				</xsd:choice>				
+				</xsd:choice>
 			</xsd:extension>
 		</xsd:complexContent>
 	</xsd:complexType>

spring-boot-project/spring-boot-tools/spring-boot-maven-plugin/src/test/java/org/springframework/boot/maven/CustomLayersProviderTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2021 the original author or authors.
+ * Copyright 2012-2022 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.
@@ -97,6 +97,7 @@ class CustomLayersProviderTests {
 		ClassPathResource resource = new ClassPathResource(resourceName);
 		InputSource inputSource = new InputSource(resource.getInputStream());
 		DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
+		factory.setNamespaceAware(true);
 		DocumentBuilder documentBuilder = factory.newDocumentBuilder();
 		return documentBuilder.parse(inputSource);
 	}