INT-3973: SFTP - Support chmod

JIRA: https://jira.spring.io/browse/INT-3973

Add `chmod` to outbound adapter and gateway (put methods).

Polishing - PR Comments

Fix Checkstyle vulnerabilities

spring-integration-file/src/main/java/org/springframework/integration/file/config/AbstractRemoteFileOutboundGatewayParser.java

@@ -81,9 +81,14 @@ public abstract class AbstractRemoteFileOutboundGatewayParser extends AbstractCo
 		IntegrationNamespaceUtils.setValueIfAttributeDefined(builder, element, "local-filename-generator-expression",
 				"localFilenameGeneratorExpressionString");
 		IntegrationNamespaceUtils.setValueIfAttributeDefined(builder, element, "mode", "fileExistsMode");
+		postProcessBuilder(builder, element);
 		return builder;
 	}
 
+	protected void postProcessBuilder(BeanDefinitionBuilder builder, Element element) {
+		// no-op
+	}
+
 	protected void configureFilter(BeanDefinitionBuilder builder, Element element, ParserContext parserContext,
 			String filterAttribute, String patternPrefix, String propertyName) {
 		String filter = element.getAttribute(filterAttribute);

spring-integration-file/src/main/java/org/springframework/integration/file/config/RemoteFileOutboundChannelAdapterParser.java

@@ -38,7 +38,7 @@ public abstract class RemoteFileOutboundChannelAdapterParser extends AbstractOut
 
 	@Override
 	protected AbstractBeanDefinition parseConsumer(Element element, ParserContext parserContext) {
-		BeanDefinitionBuilder handlerBuilder = BeanDefinitionBuilder.genericBeanDefinition(FileTransferringMessageHandler.class);
+		BeanDefinitionBuilder handlerBuilder = BeanDefinitionBuilder.genericBeanDefinition(handlerClass());
 
 		BeanDefinition templateDefinition = FileParserUtils.parseRemoteFileTemplate(element, parserContext, true,
 				getTemplateClass());
@@ -48,9 +48,18 @@ public abstract class RemoteFileOutboundChannelAdapterParser extends AbstractOut
 		if (StringUtils.hasText(mode)) {
 			handlerBuilder.addConstructorArgValue(mode);
 		}
+		postProcessBuilder(handlerBuilder, element);
 		return handlerBuilder.getBeanDefinition();
 	}
 
+	protected Class<?> handlerClass() {
+		return FileTransferringMessageHandler.class;
+	}
+
+	protected void postProcessBuilder(BeanDefinitionBuilder builder, Element element) {
+		// no-op
+	}
+
 	protected abstract Class<? extends RemoteFileOperations<?>> getTemplateClass();
 
 }

spring-integration-file/src/main/java/org/springframework/integration/file/remote/gateway/AbstractRemoteFileOutboundGateway.java

@@ -230,6 +230,8 @@ public abstract class AbstractRemoteFileOutboundGateway<F> extends AbstractReply
 
 	private volatile FileExistsMode fileExistsMode;
 
+	private volatile Integer chmod;
+
 	/**
 	 * Construct an instance using the provided session factory and callback for
 	 * performing operations on the session.
@@ -430,6 +432,32 @@ public abstract class AbstractRemoteFileOutboundGateway<F> extends AbstractReply
 		}
 	}
 
+	/**
+	 * String setter for Spring XML convenience.
+	 * @param chmod permissions as an octal string e.g "600";
+	 * @see #setChmod(int)
+	 * @since 4.3
+	 */
+	public void setChmodOctal(String chmod) {
+		Assert.notNull(chmod, "'chmod' cannot be null");
+		setChmod(Integer.parseInt(chmod, 8));
+	}
+
+	/**
+	 * Set the file permissions after uploading, e.g. 0600 for
+	 * owner read/write.
+	 * @param chmod the permissions.
+	 * @since 4.3
+	 */
+	public void setChmod(int chmod) {
+		Assert.isTrue(isChmodCapable(), "chmod operations not supported");
+		this.chmod = chmod;
+	}
+
+	public boolean isChmodCapable() {
+		return false;
+	}
+
 	@Override
 	protected void doInit() {
 		Assert.state(this.command != null || this.messageSessionCallback != null,
@@ -616,9 +644,24 @@ public abstract class AbstractRemoteFileOutboundGateway<F> extends AbstractReply
 		if (path == null) {
 			throw new MessagingException(requestMessage, "No local file found for " + requestMessage);
 		}
+		if (this.chmod != null && isChmodCapable()) {
+			doChmod(this.remoteFileTemplate, path, this.chmod);
+		}
 		return path;
 	}
 
+	/**
+	 * Set the mode on the remote file after transfer; the default implementation does
+	 * nothing.
+	 * @param remoteFileTemplate the remote file template.
+	 * @param path the path.
+	 * @param chmod the chmod to set.
+	 * @since 4.3
+	 */
+	protected void doChmod(RemoteFileTemplate<F> remoteFileTemplate, String path, int chmod) {
+		// no-op
+	}
+
 	private Object doMput(Message<?> requestMessage) {
 		File file = null;
 		if (requestMessage.getPayload() instanceof File) {

spring-integration-file/src/main/java/org/springframework/integration/file/remote/handler/FileTransferringMessageHandler.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -42,6 +42,8 @@ public class FileTransferringMessageHandler<F> extends AbstractMessageHandler {
 
 	private final FileExistsMode mode;
 
+	private Integer chmod;
+
 	public FileTransferringMessageHandler(SessionFactory<F> sessionFactory) {
 		Assert.notNull(sessionFactory, "sessionFactory must not be null");
 		this.remoteFileTemplate = new RemoteFileTemplate<F>(sessionFactory);
@@ -131,6 +133,32 @@ public class FileTransferringMessageHandler<F> extends AbstractMessageHandler {
 		this.remoteFileTemplate.setTemporaryFileSuffix(temporaryFileSuffix);
 	}
 
+	/**
+	 * String setter for Spring XML convenience.
+	 * @param chmod permissions as an octal string e.g "600";
+	 * @see #setChmod(int)
+	 * @since 4.3
+	 */
+	public void setChmodOctal(String chmod) {
+		Assert.notNull(chmod, "'chmod' cannot be null");
+		setChmod(Integer.parseInt(chmod, 8));
+	}
+
+	/**
+	 * Set the file permissions after uploading, e.g. 0600 for
+	 * owner read/write.
+	 * @param chmod the permissions.
+	 * @since 4.3
+	 */
+	public void setChmod(int chmod) {
+		Assert.isTrue(isChmodCapable(), "chmod operations not supported");
+		this.chmod = chmod;
+	}
+
+	public boolean isChmodCapable() {
+		return false;
+	}
+
 	@Override
 	protected void onInit() throws Exception {
 		this.remoteFileTemplate.setBeanFactory(this.getBeanFactory());
@@ -139,7 +167,22 @@ public class FileTransferringMessageHandler<F> extends AbstractMessageHandler {
 
 	@Override
 	protected void handleMessageInternal(Message<?> message) throws Exception {
-		this.remoteFileTemplate.send(message, this.mode);
+		String path = this.remoteFileTemplate.send(message, this.mode);
+		if (this.chmod != null && isChmodCapable()) {
+			doChmod(this.remoteFileTemplate, path, this.chmod);
+		}
+	}
+
+	/**
+	 * Set the mode on the remote file after transfer; the default implementation does
+	 * nothing.
+	 * @param remoteFileTemplate the remote file template.
+	 * @param path the path.
+	 * @param chmod the chmod to set.
+	 * @since 4.3
+	 */
+	protected void doChmod(RemoteFileTemplate<F> remoteFileTemplate, String path, int chmod) {
+		// no-op
 	}
 
 }