INT-3622: (S)FTP: Add MessageSessionCallback

JIRA: https://jira.spring.io/browse/INT-3622

INT-3622: Polishing

spring-integration-sftp/src/main/java/org/springframework/integration/sftp/gateway/SftpOutboundGateway.java

@@ -22,6 +22,7 @@ import java.util.List;
 
 import org.springframework.beans.DirectFieldAccessor;
 import org.springframework.integration.file.remote.AbstractFileInfo;
+import org.springframework.integration.file.remote.MessageSessionCallback;
 import org.springframework.integration.file.remote.RemoteFileTemplate;
 import org.springframework.integration.file.remote.gateway.AbstractRemoteFileOutboundGateway;
 import org.springframework.integration.file.remote.session.SessionFactory;
@@ -33,19 +34,55 @@ import com.jcraft.jsch.ChannelSftp.LsEntry;
  * Outbound Gateway for performing remote file operations via SFTP.
  *
  * @author Gary Russell
+ * @author Artem Bilan
  * @since 2.1
  */
 public class SftpOutboundGateway extends AbstractRemoteFileOutboundGateway<LsEntry> {
 
+	/**
+	 * Construct an instance using the provided session factory and callback for
+	 * performing operations on the session.
+	 * @param sessionFactory the session factory.
+	 * @param messageSessionCallback the callback.
+	 */
+	public SftpOutboundGateway(SessionFactory<LsEntry> sessionFactory,
+			MessageSessionCallback<LsEntry, ?> messageSessionCallback) {
+		super(sessionFactory, messageSessionCallback);
+	}
+
+	/**
+	 * Construct an instance with the supplied remote file template and callback
+	 * for performing operations on the session.
+	 * @param remoteFileTemplate the remote file template.
+	 * @param messageSessionCallback the callback.
+	 */
+	public SftpOutboundGateway(RemoteFileTemplate<LsEntry> remoteFileTemplate,
+				MessageSessionCallback<LsEntry, ?> messageSessionCallback) {
+		super(remoteFileTemplate, messageSessionCallback);
+	}
+
+	/**
+	 * Construct an instance with the supplied session factory, a command ('ls', 'get'
+	 * etc), and an expression to determine the filename.
+	 * @param sessionFactory the session factory.
+	 * @param command the command.
+	 * @param expression the filename expression.
+	 */
 	public SftpOutboundGateway(SessionFactory<LsEntry> sessionFactory, String command, String expression) {
 		super(sessionFactory, command, expression);
 	}
 
+	/**
+	 * Construct an instance with the supplied remote file template, a command ('ls',
+	 * 'get' etc), and an expression to determine the filename.
+	 * @param remoteFileTemplate the remote file template.
+	 * @param command the command.
+	 * @param expression the filename expression.
+	 */
 	public SftpOutboundGateway(RemoteFileTemplate<LsEntry> remoteFileTemplate, String command, String expression) {
 		super(remoteFileTemplate, command, expression);
 	}
 
-
 	@Override
 	protected boolean isDirectory(LsEntry file) {
 		return file.getAttrs().isDir();

spring-integration-sftp/src/main/resources/org/springframework/integration/sftp/config/spring-integration-sftp-4.2.xsd

@@ -250,7 +250,7 @@
 						<xsd:element name="request-handler-advice-chain" type="integration:handlerAdviceChainType"
 									 minOccurs="0" maxOccurs="1" />
 					</xsd:all>
-					<xsd:attribute name="command" use="required">
+					<xsd:attribute name="command">
 						<xsd:annotation>
 							<xsd:documentation>
 								sftp command.
@@ -260,6 +260,20 @@
 							<xsd:union memberTypes="int-file:remoteGatewayCommand xsd:string"/>
 						</xsd:simpleType>
 					</xsd:attribute>
+					<xsd:attribute name="session-callback" type="xsd:string">
+						<xsd:annotation>
+							<xsd:appinfo>
+								<tool:annotation kind="ref">
+									<tool:expected-type
+											type="org.springframework.integration.file.remote.MessageSessionCallback" />
+								</tool:annotation>
+							</xsd:appinfo>
+							<xsd:documentation>
+								The 'MessageSessionCallback' bean reference to perform custom operation(s) on 'Session'
+								with 'requestMessage'.
+							</xsd:documentation>
+						</xsd:annotation>
+					</xsd:attribute>
 					<xsd:attribute name="command-options" type="xsd:string">
 						<xsd:annotation>
 							<xsd:documentation>
@@ -276,7 +290,7 @@
 							</xsd:documentation>
 						</xsd:annotation>
 					</xsd:attribute>
-					<xsd:attribute name="expression" use="required" type="xsd:string">
+					<xsd:attribute name="expression" type="xsd:string">
 						<xsd:annotation>
 							<xsd:documentation>
 								SpEL expression representing the path in the

spring-integration-sftp/src/test/java/org/springframework/integration/sftp/outbound/SftpServerOutboundTests-context.xml

@@ -153,4 +153,13 @@
 	<int:service-activator input-channel="markers"
 	  expression="payload.mark.toString().equals('END') ? headers['file_remoteSession'].close() : null"/>
 
+	<int-sftp:outbound-gateway
+			session-factory="sftpSessionFactory"
+			session-callback="messageSessionCallback"
+			request-channel="inboundCallback"
+			reply-channel="output"/>
+
+	<bean id="messageSessionCallback"
+		  class="org.springframework.integration.sftp.outbound.SftpServerOutboundTests$TestMessageSessionCallback"/>
+
 </beans>

spring-integration-sftp/src/test/java/org/springframework/integration/sftp/outbound/SftpServerOutboundTests.java

@@ -47,6 +47,7 @@ import org.junit.runner.RunWith;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.integration.channel.DirectChannel;
 import org.springframework.integration.file.FileHeaders;
+import org.springframework.integration.file.remote.MessageSessionCallback;
 import org.springframework.integration.file.remote.SessionCallback;
 import org.springframework.integration.file.remote.session.Session;
 import org.springframework.integration.sftp.TestSftpServer;
@@ -62,6 +63,7 @@ import org.springframework.test.context.ContextConfiguration;
 import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
 import org.springframework.util.FileCopyUtils;
 
+import com.jcraft.jsch.ChannelSftp;
 import com.jcraft.jsch.ChannelSftp.LsEntry;
 
 /**
@@ -129,6 +131,9 @@ public class SftpServerOutboundTests {
 	@Autowired
 	private DirectChannel inboundGetStream;
 
+	@Autowired
+	private DirectChannel inboundCallback;
+
 	@Before
 	@After
 	public void setup() {
@@ -420,6 +425,14 @@ public class SftpServerOutboundTests {
 		assertFalse(((Session<?>) result.getHeaders().get(FileHeaders.REMOTE_SESSION)).isOpen());
 	}
 
+	@Test
+	public void testMessageSessionCallback() {
+		this.inboundCallback.send(new GenericMessage<String>("foo"));
+		Message<?> receive = this.output.receive(10000);
+		assertNotNull(receive);
+		assertEquals("FOO", receive.getPayload());
+	}
+
 	private void assertLength6(SftpRemoteFileTemplate template) {
 		LsEntry[] files = template.execute(new SessionCallback<LsEntry, LsEntry[]>() {
 
@@ -432,4 +445,14 @@ public class SftpServerOutboundTests {
 		assertEquals(6, files[0].getAttrs().getSize());
 	}
 
+	private static final class TestMessageSessionCallback
+			implements MessageSessionCallback<LsEntry, Object> {
+
+		@Override
+		public Object doInSession(Session<ChannelSftp.LsEntry> session, Message<?> requestMessage) throws IOException {
+			return ((String) requestMessage.getPayload()).toUpperCase();
+		}
+
+	}
+
 }