Support proxy settings for Aether Module resolver

- Add `AetherProxyProperties` as a ConfigurationProperties for the proxy settings needed for the ProxySelector in Aether system
 - Update proxy settings in two places:
   1) Where the remote repositories are setup
   2) WHere the repository system session is created to resolve the artifacts

This resolves #272

Set authentication only for proxy settings

Set port type to `int`

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2015 the original author or authors.
+ * Copyright 2015-2016 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.
@@ -34,7 +34,11 @@ import org.eclipse.aether.collection.CollectRequest;
 import org.eclipse.aether.connector.basic.BasicRepositoryConnectorFactory;
 import org.eclipse.aether.graph.Dependency;
 import org.eclipse.aether.impl.DefaultServiceLocator;
+import org.eclipse.aether.repository.Authentication;
+import org.eclipse.aether.repository.AuthenticationContext;
+import org.eclipse.aether.repository.AuthenticationDigest;
 import org.eclipse.aether.repository.LocalRepository;
+import org.eclipse.aether.repository.Proxy;
 import org.eclipse.aether.repository.RemoteRepository;
 import org.eclipse.aether.resolution.ArtifactRequest;
 import org.eclipse.aether.resolution.ArtifactResolutionException;
@@ -47,6 +51,7 @@ import org.eclipse.aether.spi.connector.transport.TransporterFactory;
 import org.eclipse.aether.transport.file.FileTransporterFactory;
 import org.eclipse.aether.transport.http.HttpTransporterFactory;
 import org.eclipse.aether.util.artifact.JavaScopes;
+import org.eclipse.aether.util.repository.DefaultProxySelector;
 
 import org.springframework.core.io.FileSystemResource;
 import org.springframework.core.io.Resource;
@@ -63,6 +68,7 @@ import org.springframework.util.StringUtils;
  * @author David Turanski
  * @author Mark Fisher
  * @author Marius Bogoevici
+ * @author Ilayaperumal Gopinathan
  */
 public class AetherModuleResolver implements ModuleResolver {
 
@@ -78,13 +84,19 @@ public class AetherModuleResolver implements ModuleResolver {
 
 	private volatile boolean offline = false;
 
+	private final AetherProxyProperties proxyProperties;
+
+	private Authentication authentication;
+
 	/**
 	 * Create an instance specifying the locations of the local and remote repositories.
 	 * @param localRepository the root path of the local maven repository
 	 * @param remoteRepositories a Map containing pairs of (repository ID,repository URL). This
 	 * may be null or empty if the local repository is off line.
+	 * @param proxyProperties the proxy properties for the maven proxy settings.
 	 */
-	public AetherModuleResolver(File localRepository, Map<String, String> remoteRepositories) {
+	public AetherModuleResolver(File localRepository, Map<String, String> remoteRepositories,
+			final AetherProxyProperties proxyProperties) {
 		Assert.notNull(localRepository, "Local repository path cannot be null");
 		if (log.isDebugEnabled()) {
 			log.debug("Local repository: " + localRepository);
@@ -93,6 +105,22 @@ public class AetherModuleResolver implements ModuleResolver {
 				log.debug("Remote repositories: " + StringUtils.collectionToCommaDelimitedString(remoteRepositories.values()));
 			}
 		}
+		this.proxyProperties = proxyProperties;
+		if (isProxyEnabled() && proxyHasCredentials()) {
+			this.authentication = new Authentication() {
+				@Override
+				public void fill(AuthenticationContext context, String key, Map<String, String> data) {
+					context.put(context.USERNAME, proxyProperties.getAuth().getUsername());
+					context.put(context.PASSWORD, proxyProperties.getAuth().getPassword());
+				}
+
+				@Override
+				public void digest(AuthenticationDigest digest) {
+					digest.update(AuthenticationContext.USERNAME, proxyProperties.getAuth().getUsername(),
+							AuthenticationContext.PASSWORD, proxyProperties.getAuth().getPassword());
+				}
+			};
+		}
 		if (!localRepository.exists()) {
 			Assert.isTrue(localRepository.mkdirs(),
 					"Unable to create directory for local repository: " + localRepository);
@@ -101,14 +129,38 @@ public class AetherModuleResolver implements ModuleResolver {
 		this.remoteRepositories = new LinkedList<>();
 		if (!CollectionUtils.isEmpty(remoteRepositories)) {
 			for (Map.Entry<String, String> remoteRepo : remoteRepositories.entrySet()) {
-				RemoteRepository remoteRepository = new RemoteRepository.Builder(remoteRepo.getKey(),
-						DEFAULT_CONTENT_TYPE, remoteRepo.getValue()).build();
-				this.remoteRepositories.add(remoteRepository);
+				RemoteRepository.Builder remoteRepositoryBuilder = new RemoteRepository.Builder(remoteRepo.getKey(),
+						DEFAULT_CONTENT_TYPE, remoteRepo.getValue());
+				if (this.authentication != null) {
+					//todo: Set direct authentication for the remote repositories
+					remoteRepositoryBuilder.setProxy(new Proxy(proxyProperties.getProtocol(), proxyProperties.getHost(),
+							proxyProperties.getPort(), authentication));
+				}
+				this.remoteRepositories.add(remoteRepositoryBuilder.build());
 			}
 		}
 		repositorySystem = newRepositorySystem();
 	}
 
+	/**
+	 * Check if the proxy settings are provided.
+	 *
+	 * @return boolean true if the proxy settings are provided.
+	 */
+	private boolean isProxyEnabled() {
+		return (this.proxyProperties != null && this.proxyProperties.getHost() != null && proxyProperties.getPort() > 0);
+	}
+
+	/**
+	 * Check if the proxy setting has username/password set.
+	 *
+	 * @return boolean true if both the username/password are set
+	 */
+	private boolean proxyHasCredentials() {
+		return (this.proxyProperties != null && this.proxyProperties.getAuth() != null &&
+				this.proxyProperties.getAuth().getUsername() != null && this.proxyProperties.getAuth().getPassword() != null);
+	}
+
 	public void setOffline(boolean offline) {
 		this.offline = offline;
 	}
@@ -133,6 +185,13 @@ public class AetherModuleResolver implements ModuleResolver {
 		LocalRepository localRepo = new LocalRepository(localRepoPath);
 		session.setLocalRepositoryManager(system.newLocalRepositoryManager(session, localRepo));
 		session.setOffline(this.offline);
+		if (isProxyEnabled()) {
+			DefaultProxySelector proxySelector = new DefaultProxySelector();
+			Proxy proxy = new Proxy(proxyProperties.getProtocol(), proxyProperties.getHost(), proxyProperties.getPort(),
+					authentication);
+			proxySelector.add(proxy, proxyProperties.getNonProxyHosts());
+			session.setProxySelector(proxySelector);
+		}
 		return session;
 	}
 
@@ -214,7 +273,8 @@ public class AetherModuleResolver implements ModuleResolver {
 						result.add(toResource(artifactResult));
 					}
 				}
-			} catch (DependencyResolutionException e) {
+			}
+			catch (DependencyResolutionException e) {
 				throw new RuntimeException(e);
 			}
 		}

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

@@ -0,0 +1,118 @@
+/*
+ * Copyright 2016 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 org.springframework.boot.context.properties.ConfigurationProperties;
+
+/**
+ * Proxy properties for the Aether Module Resolver.
+ *
+ * @author Ilayaperumal Gopinathan
+ */
+@ConfigurationProperties(prefix = "aether.proxy")
+public class AetherProxyProperties {
+	/**
+	 * Protocol to use for proxy settings.
+	 */
+	private String protocol = "http";
+
+	/**
+	 * Host for the proxy.
+	 */
+	private String host;
+
+	/**
+	 * Port for the proxy.
+	 */
+	private int port;
+
+	/**
+	 * List of non proxy hosts.
+	 */
+	private String nonProxyHosts;
+
+	private Authentication auth;
+
+	public String getProtocol() {
+		return this.protocol;
+	}
+
+	public void setProtocol(String protocol) {
+		this.protocol = protocol;
+	}
+
+	public String getHost() {
+		return this.host;
+	}
+
+	public void setHost(String host) {
+		this.host = host;
+	}
+
+	public int getPort() {
+		return this.port;
+	}
+
+	public void setPort(int port) {
+		this.port = port;
+	}
+
+	public String getNonProxyHosts() {
+		return this.nonProxyHosts;
+	}
+
+	public void setNonProxyHosts(String nonProxyHosts) {
+		this.nonProxyHosts = nonProxyHosts;
+	}
+
+	public Authentication getAuth() {
+		return this.auth;
+	}
+
+	public void setAuth(Authentication auth) {
+		this.auth = auth;
+	}
+
+	public static class Authentication {
+
+		/**
+		 * Username for the proxy.
+		 */
+		private String username;
+
+		/**
+		 * Password for the proxy.
+		 */
+		private String password;
+
+		public String getUsername() {
+			return this.username;
+		}
+
+		public void setUsername(String username) {
+			this.username = username;
+		}
+
+		public String getPassword() {
+			return this.password;
+		}
+
+		public void setPassword(String password) {
+			this.password = password;
+		}
+
+	}
+}

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2015 the original author or authors.
+ * Copyright 2015-2016 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.
@@ -28,22 +28,27 @@ import org.springframework.context.annotation.Bean;
  * Sets up the default Aether-based module resolver, unless overridden.
  *
  * @author Eric Bottard
+ * @author Ilayaperumal Gopinathan
  */
-@EnableConfigurationProperties(ModuleResolverProperties.class)
+@EnableConfigurationProperties({ModuleResolverProperties.class, AetherProxyProperties.class})
 public class ModuleResolverConfiguration {
 
 	@Autowired
 	private ModuleResolverProperties properties;
 
+	@Autowired
+	private AetherProxyProperties proxyProperties;
+
 	@Bean
 	@ConditionalOnMissingBean(ModuleResolver.class)
 	public ModuleResolver moduleResolver() {
 		int i = 1;
 		Map<String, String> repositoriesMap = new HashMap<>();
-		for (String repository: properties.getRemoteRepositories()) {
+		for (String repository : properties.getRemoteRepositories()) {
 			repositoriesMap.put("repository " + i++, repository);
 		}
-		AetherModuleResolver aetherModuleResolver = new AetherModuleResolver(properties.getLocalRepository(), repositoriesMap);
+		AetherModuleResolver aetherModuleResolver = new AetherModuleResolver(properties.getLocalRepository(),
+				repositoriesMap, proxyProperties);
 		aetherModuleResolver.setOffline(properties.isOffline());
 		return aetherModuleResolver;
 	}

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

@@ -51,6 +51,7 @@ public class ModuleResolverProperties {
 	public String[] getRemoteRepositories() {
 		return remoteRepositories;
 	}
+
 	public void setLocalRepository(File localRepository) {
 		this.localRepository = localRepository;
 	}

spring-cloud-stream-module-launcher/src/test/java/org/springframework/cloud/stream/module/resolver/AetherModuleResolverTests.java

@@ -20,14 +20,10 @@ import static com.github.tomakehurst.wiremock.client.WireMock.aResponse;
 import static com.github.tomakehurst.wiremock.client.WireMock.get;
 import static com.github.tomakehurst.wiremock.client.WireMock.stubFor;
 import static com.github.tomakehurst.wiremock.client.WireMock.urlEqualTo;
-import static org.hamcrest.Matchers.arrayContaining;
 import static org.hamcrest.Matchers.arrayContainingInAnyOrder;
 import static org.hamcrest.Matchers.arrayWithSize;
 import static org.hamcrest.Matchers.containsString;
-import static org.hamcrest.Matchers.equalTo;
 import static org.hamcrest.Matchers.instanceOf;
-import static org.hamcrest.Matchers.not;
-import static org.hamcrest.beans.HasPropertyWithValue.hasProperty;
 import static org.hamcrest.object.HasToString.hasToString;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertThat;
@@ -65,7 +61,7 @@ public class AetherModuleResolverTests {
 	public void testResolveLocal() throws IOException {
 		ClassPathResource cpr = new ClassPathResource("local-repo");
 		File localRepository = cpr.getFile();
-		AetherModuleResolver defaultModuleResolver = new AetherModuleResolver(localRepository, null);
+		AetherModuleResolver defaultModuleResolver = new AetherModuleResolver(localRepository, null, null);
 		Resource resource = defaultModuleResolver.resolve(new Coordinates("foo.bar", "foo-bar", "jar", "", "1.0.0"));
 		assertTrue(resource.exists());
 		assertEquals(resource.getFile().getName(), "foo-bar-1.0.0.jar");
@@ -75,7 +71,7 @@ public class AetherModuleResolverTests {
 	public void testResolveLocalWithIncludes() throws IOException {
 		ClassPathResource cpr = new ClassPathResource("local-repo");
 		File localRepository = cpr.getFile();
-		AetherModuleResolver defaultModuleResolver = new AetherModuleResolver(localRepository, null);
+		AetherModuleResolver defaultModuleResolver = new AetherModuleResolver(localRepository, null, null);
 		Resource[] resources = defaultModuleResolver.resolve(
 				new Coordinates("foo.bar", "foo-bar", "jar", "", "1.0.0"),
 				new Coordinates[]{new Coordinates("qux.bar", "qux-bar", "jar", "", "1.0.0")},new String[]{});
@@ -92,7 +88,7 @@ public class AetherModuleResolverTests {
 	public void testResolveDoesNotExist() throws IOException {
 		ClassPathResource cpr = new ClassPathResource("local-repo");
 		File localRepository = cpr.getFile();
-		AetherModuleResolver defaultModuleResolver = new AetherModuleResolver(localRepository, null);
+		AetherModuleResolver defaultModuleResolver = new AetherModuleResolver(localRepository, null, null);
 		defaultModuleResolver.resolve(new Coordinates("niente", "nada", "jar", "", "zilch"));
 	}
 
@@ -103,7 +99,7 @@ public class AetherModuleResolverTests {
 		localRepository.deleteOnExit();
 		Map<String, String> remoteRepos = new HashMap<>();
 		remoteRepos.put("modules", "http://repo.spring.io/libs-snapshot");
-		AetherModuleResolver defaultModuleResolver = new AetherModuleResolver(localRepository, remoteRepos);
+		AetherModuleResolver defaultModuleResolver = new AetherModuleResolver(localRepository, remoteRepos, null);
 		Resource resource = defaultModuleResolver.resolve(
 				new Coordinates("org.springframework.cloud.stream.module", "time-source", "jar", "exec", "1.0.0.BUILD-SNAPSHOT"));
 		assertTrue(resource.exists());
@@ -123,7 +119,7 @@ public class AetherModuleResolverTests {
 				.willReturn(aResponse()
 						.withStatus(200)
 						.withBodyFile(stubFileName)));
-		AetherModuleResolver defaultModuleResolver = new AetherModuleResolver(localRepository, remoteRepos);
+		AetherModuleResolver defaultModuleResolver = new AetherModuleResolver(localRepository, remoteRepos, null);
 		Resource resource = defaultModuleResolver.resolve(new Coordinates("org.bar", "foo", "jar", "", "1.0.0"));
 		assertTrue(resource.exists());
 		assertEquals(resource.getFile().getName(), "foo-1.0.0.jar");
@@ -143,7 +139,7 @@ public class AetherModuleResolverTests {
 					.willReturn(aResponse()
 							.withStatus(200)
 							.withBodyFile(stubFileName)));
-			AetherModuleResolver defaultModuleResolver = new AetherModuleResolver(localRepository, remoteRepos);
+			AetherModuleResolver defaultModuleResolver = new AetherModuleResolver(localRepository, remoteRepos, null);
 			defaultModuleResolver.setOffline(true);
 			defaultModuleResolver.resolve(new Coordinates("org.bar", "foo", "jar", "", "1.0.0"));
 		} catch (RuntimeException e) {