XD-3355, XD-3582: Support options metadata

pom.xml

@@ -33,6 +33,7 @@
 		<module>spring-cloud-stream-module-launcher</module>
 		<module>docs</module>
 		<module>spring-cloud-stream-test-support</module>
+		<module>spring-cloud-stream-configuration-metadata</module>
 	</modules>
 	<dependencyManagement>
 		<dependencies>

spring-cloud-stream-configuration-metadata/pom.xml

@@ -0,0 +1,26 @@
+<?xml version="1.0"?>
+<project xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"
+		 xmlns="http://maven.apache.org/POM/4.0.0"
+		 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
+	<modelVersion>4.0.0</modelVersion>
+	<parent>
+		<groupId>org.springframework.cloud</groupId>
+		<artifactId>spring-cloud-stream-parent</artifactId>
+		<version>1.0.0.BUILD-SNAPSHOT</version>
+	</parent>
+	<artifactId>spring-cloud-stream-configuration-metadata</artifactId>
+	<properties>
+		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+	</properties>
+
+	<dependencies>
+		<dependency>
+			<groupId>org.springframework.cloud</groupId>
+			<artifactId>spring-cloud-stream-module-launcher</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-configuration-metadata</artifactId>
+		</dependency>
+	</dependencies>
+</project>

spring-cloud-stream-configuration-metadata/src/main/java/org/springframework/cloud/stream/configuration/metadata/ModuleConfigurationMetadataResolver.java

@@ -0,0 +1,116 @@
+/*
+ * Copyright 2015 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
+ *
+ *      http://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.cloud.stream.configuration.metadata;
+
+import java.io.Closeable;
+import java.io.File;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
+
+import org.springframework.boot.configurationmetadata.ConfigurationMetadataProperty;
+import org.springframework.boot.configurationmetadata.ConfigurationMetadataRepositoryJsonBuilder;
+import org.springframework.boot.loader.archive.Archive;
+import org.springframework.boot.loader.archive.ExplodedArchive;
+import org.springframework.boot.loader.archive.JarFileArchive;
+import org.springframework.boot.loader.jar.JarFile;
+import org.springframework.cloud.stream.module.launcher.ModuleJarLauncher;
+import org.springframework.core.io.Resource;
+import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
+import org.springframework.core.io.support.ResourcePatternResolver;
+
+/**
+ * Used to retrieve metadata about the configuration properties that can alter a module behavior.
+ *
+ * @author Eric Bottard
+ */
+public class ModuleConfigurationMetadataResolver {
+
+	public ModuleConfigurationMetadataResolver() {
+		JarFile.registerUrlProtocolHandler();
+	}
+
+	/**
+	 * Return metadata about configuration properties that are documented via
+	 * <a href="http://docs.spring.io/spring-boot/docs/current/reference/html/configuration-metadata.html">
+	 * Spring Boot configuration metadata</a> and visible in a module.
+	 *
+	 * @param module a Spring Cloud Stream module; typically a Boot uberjar,
+	 * but directories are supported as well
+	 */
+	public List<ConfigurationMetadataProperty> listProperties(Resource module) {
+		List<ConfigurationMetadataProperty> result = new ArrayList<>();
+		ClassLoader classLoader = null;
+		try {
+			File moduleFile = module.getFile();
+			Archive archive = moduleFile.isDirectory() ? new ExplodedArchive(moduleFile) : new JarFileArchive(moduleFile);
+			classLoader = createClassLoader(archive);
+			ConfigurationMetadataRepositoryJsonBuilder builder = ConfigurationMetadataRepositoryJsonBuilder.create();
+			ResourcePatternResolver moduleResourceLoader = new PathMatchingResourcePatternResolver(classLoader);
+			for (Resource r : moduleResourceLoader.getResources("classpath*:/META-INF/*spring-configuration-metadata.json")) {
+				builder.withJsonResource(r.getInputStream());
+			}
+			for (ConfigurationMetadataProperty property : builder.build().getAllProperties().values()) {
+						result.add(property);
+			}
+		}
+		catch (Exception e) {
+			throw new RuntimeException("Exception trying to list configuration properties for module " + module, e);
+		}
+		finally {
+			if (classLoader instanceof Closeable) {
+				try {
+					((Closeable) classLoader).close();
+				}
+				catch (IOException e) {
+					// ignore
+				}
+			}
+		}
+		return result;
+	}
+
+	/**
+	 * Return a {@link ClassLoader} for accessing resources in the provided
+	 * {@link Archive}. The caller is responsible for disposing of the
+	 * class loader.
+	 *
+	 * @param archive the archive for which to return a class loader
+	 * @return class loader for the given archive
+	 * @throws Exception if the class loader cannot be created
+	 */
+	protected ClassLoader createClassLoader(Archive archive) throws Exception {
+		return new ClassLoaderExposingJarLauncher(archive).createClassLoader();
+	}
+
+
+	/**
+	 * Extension of {@link ModuleJarLauncher} used for exposing a {@link ClassLoader}
+	 * for the provided {@link Archive}.
+	 */
+	private static class ClassLoaderExposingJarLauncher extends ModuleJarLauncher {
+
+		public ClassLoaderExposingJarLauncher(Archive archive) {
+			super(archive);
+		}
+
+		protected ClassLoader createClassLoader() throws Exception {
+			List<Archive> classPathArchives = getClassPathArchives();
+			return createClassLoader(classPathArchives);
+		}
+	}
+}

spring-cloud-stream-configuration-metadata/src/main/java/org/springframework/cloud/stream/configuration/metadata/ModuleConfigurationMetadataResolverAutoConfiguration.java

@@ -0,0 +1,36 @@
+/*
+ * Copyright 2015 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
+ *
+ *      http://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.cloud.stream.configuration.metadata;
+
+import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Bean;
+
+/**
+ * Automatically exposes a ModuleConfigurationMetadataResolver if none is already registered.
+ *
+ * @author Eric Bottard
+ */
+@Configuration
+public class ModuleConfigurationMetadataResolverAutoConfiguration {
+
+	@Bean
+	@ConditionalOnMissingBean(ModuleConfigurationMetadataResolver.class)
+	public ModuleConfigurationMetadataResolver metadataResolver() {
+		return new ModuleConfigurationMetadataResolver();
+	}
+}

spring-cloud-stream-configuration-metadata/src/main/resources/META-INF/spring.factories

@@ -0,0 +1,2 @@
+org.springframework.boot.autoconfigure.EnableAutoConfiguration:\
+org.springframework.cloud.stream.configuration.metadata.ModuleConfigurationMetadataResolverAutoConfiguration

spring-cloud-stream-module-launcher/src/main/java/org/springframework/cloud/stream/module/launcher/ModuleJarLauncher.java

@@ -29,8 +29,8 @@ import org.springframework.util.ReflectionUtils;
 /**
  * A {@link JarLauncher} that supports launching module archive.
  *
- * Also, it restricts the classloader of the launched application to the contents of the uber-jar and the
- * extension classloader of the JVM.
+ * Also, it restricts the classloader of the launched application to the contents
+ * of the uber-jar and the extension classloader of the JVM.
  *
  * @author Mark Fisher
  * @author Marius Bogoevici

spring-cloud-stream-module-launcher/src/main/java/org/springframework/cloud/stream/module/launcher/ModuleLauncherConfiguration.java

@@ -16,17 +16,11 @@
 
 package org.springframework.cloud.stream.module.launcher;
 
-import java.util.HashMap;
-import java.util.Map;
-
-import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
-import org.springframework.boot.context.properties.EnableConfigurationProperties;
-import org.springframework.cloud.stream.module.resolver.AetherModuleResolver;
 import org.springframework.cloud.stream.module.resolver.ModuleResolver;
-import org.springframework.cloud.stream.module.resolver.ModuleResolverProperties;
+import org.springframework.cloud.stream.module.resolver.ModuleResolverConfiguration;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Import;
 
 /**
  * Configuration class that has the beans required for module launcher.
@@ -36,28 +30,9 @@ import org.springframework.context.annotation.Configuration;
  * @author Eric Bottard
  */
 @Configuration
-@EnableConfigurationProperties(ModuleResolverProperties.class)
+@Import(ModuleResolverConfiguration.class)
 public class ModuleLauncherConfiguration {
 
-	@Autowired
-	private ModuleResolverProperties properties;
-
-	/**
-	 * Sets up the default Aether-based module resolver, unless overridden.
-	 */
-	@Bean
-	@ConditionalOnMissingBean(ModuleResolver.class)
-	public ModuleResolver moduleResolver() {
-		int i = 1;
-		Map<String, String> repositoriesMap = new HashMap<>();
-		for (String repository: properties.getRemoteRepositories()) {
-			repositoriesMap.put("repository " + i++, repository);
-		}
-		AetherModuleResolver aetherModuleResolver = new AetherModuleResolver(properties.getLocalRepository(), repositoriesMap);
-		aetherModuleResolver.setOffline(properties.isOffline());
-		return aetherModuleResolver;
-	}
-
 	@Bean
 	public ModuleLauncher moduleLauncher(ModuleResolver moduleResolver) {
 		return new ModuleLauncher(moduleResolver);

spring-cloud-stream-module-launcher/src/main/java/org/springframework/cloud/stream/module/resolver/ModuleResolverConfiguration.java

@@ -0,0 +1,50 @@
+/*
+ * Copyright 2015 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
+ *
+ *      http://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.cloud.stream.module.resolver;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
+import org.springframework.boot.context.properties.EnableConfigurationProperties;
+import org.springframework.context.annotation.Bean;
+
+/**
+ * Sets up the default Aether-based module resolver, unless overridden.
+ *
+ * @author Eric Bottard
+ */
+@EnableConfigurationProperties(ModuleResolverProperties.class)
+public class ModuleResolverConfiguration {
+
+	@Autowired
+	private ModuleResolverProperties properties;
+
+	@Bean
+	@ConditionalOnMissingBean(ModuleResolver.class)
+	public ModuleResolver moduleResolver() {
+		int i = 1;
+		Map<String, String> repositoriesMap = new HashMap<>();
+		for (String repository: properties.getRemoteRepositories()) {
+			repositoriesMap.put("repository " + i++, repository);
+		}
+		AetherModuleResolver aetherModuleResolver = new AetherModuleResolver(properties.getLocalRepository(), repositoriesMap);
+		aetherModuleResolver.setOffline(properties.isOffline());
+		return aetherModuleResolver;
+	}
+}