Include LICENCE and NOTICE files in shipped jars

See gh-20058

buildSrc/src/main/java/org/springframework/boot/build/ConventionsPlugin.java

@@ -16,6 +16,14 @@
 
 package org.springframework.boot.build;
 
+import java.io.File;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.net.URISyntaxException;
+import java.net.URL;
+import java.nio.charset.StandardCharsets;
+import java.time.Year;
 import java.util.List;
 import java.util.Map;
 import java.util.TreeMap;
@@ -24,9 +32,11 @@ import io.spring.javaformat.gradle.FormatTask;
 import io.spring.javaformat.gradle.SpringJavaFormatPlugin;
 import org.apache.maven.artifact.repository.MavenArtifactRepository;
 import org.asciidoctor.gradle.jvm.AsciidoctorJPlugin;
+import org.gradle.api.GradleException;
 import org.gradle.api.Plugin;
 import org.gradle.api.Project;
 import org.gradle.api.artifacts.DependencySet;
+import org.gradle.api.file.CopySpec;
 import org.gradle.api.plugins.JavaBasePlugin;
 import org.gradle.api.plugins.JavaPlugin;
 import org.gradle.api.plugins.JavaPluginExtension;
@@ -42,12 +52,14 @@ import org.gradle.api.publish.maven.MavenPomScm;
 import org.gradle.api.publish.maven.MavenPublication;
 import org.gradle.api.publish.maven.plugins.MavenPublishPlugin;
 import org.gradle.api.publish.tasks.GenerateModuleMetadata;
+import org.gradle.api.resources.TextResourceFactory;
 import org.gradle.api.tasks.bundling.Jar;
 import org.gradle.api.tasks.compile.JavaCompile;
 import org.gradle.api.tasks.javadoc.Javadoc;
 import org.gradle.api.tasks.testing.Test;
 
 import org.springframework.boot.build.testing.TestFailuresPlugin;
+import org.springframework.util.FileCopyUtils;
 
 /**
  * Plugin to apply conventions to projects that are part of Spring Boot's build.
@@ -127,6 +139,7 @@ public class ConventionsPlugin implements Plugin<Project> {
 			});
 			project.getTasks().withType(Jar.class, (jar) -> {
 				project.afterEvaluate((evaluated) -> {
+					jar.metaInf((metaInf) -> copyLegalFiles(project, metaInf));
 					jar.manifest((manifest) -> {
 						Map<String, Object> attributes = new TreeMap<>();
 						attributes.put("Automatic-Module-Name", project.getName().replace("-", "."));
@@ -141,6 +154,44 @@ public class ConventionsPlugin implements Plugin<Project> {
 		});
 	}
 
+	private void copyLegalFiles(Project project, CopySpec metaInf) {
+		copyNoticeFile(project, metaInf);
+		copyLicenseFile(project, metaInf);
+	}
+
+	private void copyNoticeFile(Project project, CopySpec metaInf) {
+		try {
+			InputStream notice = getClass().getClassLoader().getResourceAsStream("NOTICE.txt");
+			String noticeContent = FileCopyUtils.copyToString(new InputStreamReader(notice, StandardCharsets.UTF_8))
+					.replace("${version}", project.getVersion().toString())
+					.replace("${currentYear}", Integer.toString(Year.now().getValue()));
+			TextResourceFactory resourceFactory = project.getResources().getText();
+			File file = createLegalFile(resourceFactory.fromString(noticeContent).asFile(), "NOTICE.txt");
+			metaInf.from(file);
+		}
+		catch (IOException ex) {
+			throw new GradleException("Failed to copy NOTICE.txt", ex);
+		}
+	}
+
+	private void copyLicenseFile(Project project, CopySpec metaInf) {
+		URL license = getClass().getClassLoader().getResource("LICENSE.txt");
+		try {
+			TextResourceFactory resourceFactory = project.getResources().getText();
+			File file = createLegalFile(resourceFactory.fromUri(license.toURI()).asFile(), "LICENSE.txt");
+			metaInf.from(file);
+		}
+		catch (URISyntaxException ex) {
+			throw new GradleException("Failed to copy LICENSE.txt", ex);
+		}
+	}
+
+	private File createLegalFile(File source, String filename) {
+		File legalFile = new File(source.getParentFile(), filename);
+		source.renameTo(legalFile);
+		return legalFile;
+	}
+
 	private void configureSpringJavaFormat(Project project) {
 		project.getPlugins().apply(SpringJavaFormatPlugin.class);
 		project.getTasks().withType(FormatTask.class, (formatTask) -> formatTask.setEncoding("UTF-8"));

buildSrc/src/main/resources/NOTICE.txt

+Spring Boot ${version}
+Copyright (c) 2012-${currentYear} Pivotal, Inc.
+
+This product is licensed to you under the Apache License, Version 2.0
+(the "License"). You may not use this product except in compliance with
+the License.
\ No newline at end of file

buildSrc/src/test/java/org/springframework/boot/build/ConventionsPluginTests.java

+/*
+ * Copyright 2012-2020 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;
+
+import java.io.File;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.io.PrintWriter;
+import java.util.jar.JarEntry;
+import java.util.jar.JarFile;
+
+import org.gradle.testkit.runner.GradleRunner;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
+
+import org.springframework.util.FileCopyUtils;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Integration tests for {@link ConventionsPlugin}.
+ *
+ * @author Christoph Dreis
+ */
+class ConventionsPluginTests {
+
+	private File projectDir;
+
+	private File buildFile;
+
+	private File licenseFile;
+
+	@BeforeEach
+	void setup(@TempDir File projectDir) throws IOException {
+		this.projectDir = projectDir;
+		this.buildFile = new File(this.projectDir, "build.gradle");
+	}
+
+	@Test
+	void jarIncludesLegalFiles() throws IOException {
+		try (PrintWriter out = new PrintWriter(new FileWriter(this.buildFile))) {
+			out.println("plugins {");
+			out.println("    id 'java'");
+			out.println("    id 'org.springframework.boot.conventions'");
+			out.println("}");
+			out.println("description 'Test'");
+			out.println("jar.archiveFileName = 'test.jar'");
+		}
+		runGradle("jar");
+		File file = new File(this.projectDir, "/build/libs/test.jar");
+		assertThat(file).exists();
+		try (JarFile jar = new JarFile(file)) {
+			JarEntry license = jar.getJarEntry("META-INF/LICENSE.txt");
+			assertThat(license).isNotNull();
+			JarEntry notice = jar.getJarEntry("META-INF/NOTICE.txt");
+			assertThat(notice).isNotNull();
+			String noticeContent = FileCopyUtils.copyToString(new InputStreamReader(jar.getInputStream(notice)));
+			// Test that variables were replaced
+			assertThat(noticeContent).doesNotContain("${");
+		}
+	}
+
+	private void runGradle(String... args) {
+		GradleRunner.create().withProjectDir(this.projectDir).withArguments(args).withPluginClasspath().build();
+	}
+
+}