GH-2996: Add Resource for remote file transfer (#3231)

* GH-2996: Add Resource for remote file transfer

Fixes #2996

* Fix `RemoteFileTemplate.send()` to support a `Resource` payload
for remote file transferring content
* Code style clean up for `RemoteFileTemplate`
* Remove `volatile` for configuration properties for better performance
* Change a `charset` to the `Charset` for only once conversion from string
during configuration phase
* Fix (S)FTP tests for new functionality
* Change affected tests to JUnit 5
* Document a new feature; mention all the supported types and `FileExistsMode` constants

* * Fix language in `whats-new.adoc`

Author: artembilan

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2013-2019 the original author or authors.
+ * Copyright 2013-2020 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.
@@ -23,6 +23,8 @@
 import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.io.InputStream;
+import java.nio.charset.Charset;
+import java.nio.charset.StandardCharsets;
 import java.util.concurrent.atomic.AtomicInteger;
 
 import org.apache.commons.logging.Log;
@@ -32,6 +34,7 @@
 import org.springframework.beans.factory.BeanFactory;
 import org.springframework.beans.factory.BeanFactoryAware;
 import org.springframework.beans.factory.InitializingBean;
+import org.springframework.core.io.Resource;
 import org.springframework.expression.Expression;
 import org.springframework.integration.file.DefaultFileNameGenerator;
 import org.springframework.integration.file.FileNameGenerator;
@@ -65,7 +68,7 @@ public class RemoteFileTemplate<F> implements RemoteFileOperations<F>, Initializ
 	private final Log logger = LogFactory.getLog(this.getClass());
 
 	/**
-	 * the {@link SessionFactory} for acquiring remote file Sessions.
+	 * The {@link SessionFactory} for acquiring remote file Sessions.
 	 */
 	protected final SessionFactory<F> sessionFactory; // NOSONAR
 
@@ -76,29 +79,29 @@ public class RemoteFileTemplate<F> implements RemoteFileOperations<F>, Initializ
 
 	private final AtomicInteger activeTemplateCallbacks = new AtomicInteger();
 
-	private volatile String temporaryFileSuffix = ".writing";
+	private String temporaryFileSuffix = ".writing";
 
-	private volatile boolean autoCreateDirectory = false;
+	private boolean autoCreateDirectory = false;
 
-	private volatile boolean useTemporaryFileName = true;
+	private boolean useTemporaryFileName = true;
 
-	private volatile ExpressionEvaluatingMessageProcessor<String> directoryExpressionProcessor;
+	private ExpressionEvaluatingMessageProcessor<String> directoryExpressionProcessor;
 
-	private volatile ExpressionEvaluatingMessageProcessor<String> temporaryDirectoryExpressionProcessor;
+	private ExpressionEvaluatingMessageProcessor<String> temporaryDirectoryExpressionProcessor;
 
-	private volatile ExpressionEvaluatingMessageProcessor<String> fileNameProcessor;
+	private ExpressionEvaluatingMessageProcessor<String> fileNameProcessor;
 
-	private volatile FileNameGenerator fileNameGenerator = new DefaultFileNameGenerator();
+	private FileNameGenerator fileNameGenerator = new DefaultFileNameGenerator();
 
-	private volatile boolean fileNameGeneratorSet;
+	private boolean fileNameGeneratorSet;
 
-	private volatile String charset = "UTF-8";
+	private Charset charset = StandardCharsets.UTF_8;
 
-	private volatile String remoteFileSeparator = "/";
+	private String remoteFileSeparator = "/";
 
-	private volatile boolean hasExplicitlySetSuffix;
+	private boolean hasExplicitlySetSuffix;
 
-	private volatile BeanFactory beanFactory;
+	private BeanFactory beanFactory;
 
 	/**
 	 * Construct a {@link RemoteFileTemplate} with the supplied session factory.
@@ -216,7 +219,7 @@ public void setFileNameGenerator(FileNameGenerator fileNameGenerator) {
 	 * @param charset the charset.
 	 */
 	public void setCharset(String charset) {
-		this.charset = charset;
+		this.charset = Charset.forName(charset);
 	}
 
 	/**
@@ -264,12 +267,12 @@ public void afterPropertiesSet() {
 	}
 
 	@Override
-	public String append(final Message<?> message) {
+	public String append(Message<?> message) {
 		return append(message, null);
 	}
 
 	@Override
-	public String append(final Message<?> message, String subDirectory) {
+	public String append(Message<?> message, String subDirectory) {
 		return send(message, subDirectory, FileExistsMode.APPEND);
 	}
 
@@ -279,14 +282,14 @@ public String send(Message<?> message, FileExistsMode... mode) {
 	}
 
 	@Override
-	public String send(final Message<?> message, String subDirectory, FileExistsMode... mode) {
+	public String send(Message<?> message, String subDirectory, FileExistsMode... mode) {
 		FileExistsMode modeToUse = mode == null || mode.length < 1 || mode[0] == null
 				? FileExistsMode.REPLACE
 				: mode[0];
 		return send(message, subDirectory, modeToUse);
 	}
 
-	private String send(final Message<?> message, final String subDirectory, final FileExistsMode mode) {
+	private String send(Message<?> message, String subDirectory, FileExistsMode mode) {
 		Assert.notNull(this.directoryExpressionProcessor, "'remoteDirectoryExpression' is required");
 		Assert.isTrue(!FileExistsMode.APPEND.equals(mode) || !this.useTemporaryFileName,
 				"Cannot append when using a temporary file name");
@@ -354,17 +357,17 @@ private String doSend(Message<?> message, String subDirectory, FileExistsMode mo
 	}
 
 	@Override
-	public boolean exists(final String path) {
+	public boolean exists(String path) {
 		return execute(session -> session.exists(path));
 	}
 
 	@Override
-	public boolean remove(final String path) {
+	public boolean remove(String path) {
 		return execute(session -> session.remove(path));
 	}
 
 	@Override
-	public void rename(final String fromPath, final String toPath) {
+	public void rename(String fromPath, String toPath) {
 		Assert.hasText(fromPath, "Old filename cannot be null or empty");
 		Assert.hasText(toPath, "New filename cannot be null or empty");
 
@@ -390,7 +393,7 @@ public boolean get(Message<?> message, InputStreamCallback callback) {
 	}
 
 	@Override
-	public boolean get(final String remotePath, final InputStreamCallback callback) {
+	public boolean get(String remotePath, InputStreamCallback callback) {
 		Assert.notNull(remotePath, "'remotePath' cannot be null");
 		return execute(session -> {
 			try (InputStream inputStream = session.readRaw(remotePath)) {
@@ -419,7 +422,6 @@ public Session<F> getSession() {
 		return this.sessionFactory.getSession();
 	}
 
-	@SuppressWarnings("rawtypes")
 	@Override
 	public <T> T execute(SessionCallback<F, T> callback) {
 		Session<F> session = null;
@@ -440,7 +442,7 @@ public <T> T execute(SessionCallback<F, T> callback) {
 			if (session != null) {
 				session.dirty();
 			}
-			if (e instanceof MessagingException) {
+			if (e instanceof MessagingException) { // NOSONAR
 				throw (MessagingException) e;
 			}
 			throw new MessagingException("Failed to execute on session", e);
@@ -498,7 +500,7 @@ private StreamHolder payloadToInputStream(Message<?> message) throws MessageDeli
 				}
 			}
 			else if (payload instanceof byte[] || payload instanceof String) {
-				byte[] bytes = null;
+				byte[] bytes;
 				if (payload instanceof String) {
 					bytes = ((String) payload).getBytes(this.charset);
 					name = "String payload";
@@ -513,6 +515,12 @@ else if (payload instanceof InputStream) {
 				dataInputStream = (InputStream) payload;
 				name = "InputStream payload";
 			}
+			else if (payload instanceof Resource) {
+				Resource resource = (Resource) payload;
+				dataInputStream = resource.getInputStream();
+				String filename = resource.getFilename();
+				name = filename != null ? filename : "Resource payload";
+			}
 			else {
 				throw new IllegalArgumentException("Unsupported payload type ["
 						+ payload.getClass().getName()
@@ -563,6 +571,7 @@ private void sendFileToRemoteDirectory(InputStream inputStream, String temporary
 
 	private void doSend(Session<F> session, FileExistsMode mode, String remoteFilePath, String tempFilePath,
 			InputStream stream) throws IOException {
+
 		boolean rename = this.useTemporaryFileName;
 		if (FileExistsMode.REPLACE.equals(mode)) {
 			session.write(stream, tempFilePath);

spring-integration-file/src/test/java/org/springframework/integration/file/remote/RemoteFileTemplateTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2015-2019 the original author or authors.
+ * Copyright 2015-2020 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.
@@ -32,14 +32,16 @@
 import java.io.File;
 import java.io.IOException;
 import java.io.InputStream;
+import java.nio.file.Files;
+import java.nio.file.Path;
 import java.util.UUID;
 
-import org.junit.Before;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.rules.TemporaryFolder;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
 
 import org.springframework.beans.factory.BeanFactory;
+import org.springframework.core.io.ByteArrayResource;
 import org.springframework.expression.common.LiteralExpression;
 import org.springframework.integration.file.remote.session.Session;
 import org.springframework.integration.file.remote.session.SessionFactory;
@@ -61,13 +63,13 @@ public class RemoteFileTemplateTests {
 
 	private Session<Object> session;
 
-	@Rule
-	public TemporaryFolder folder = new TemporaryFolder();
+	@TempDir
+	Path folder;
 
 	private File file;
 
 	@SuppressWarnings("unchecked")
-	@Before
+	@BeforeEach
 	public void setUp() throws Exception {
 		SessionFactory<Object> sessionFactory = mock(SessionFactory.class);
 		this.template = new RemoteFileTemplate<>(sessionFactory);
@@ -76,7 +78,7 @@ public void setUp() throws Exception {
 		this.template.afterPropertiesSet();
 		this.session = mock(Session.class);
 		when(sessionFactory.getSession()).thenReturn(this.session);
-		this.file = this.folder.newFile();
+		this.file = Files.createTempFile(this.folder, null, null).toFile();
 	}
 
 	@Test
@@ -146,6 +148,12 @@ public void testBytes() throws IOException {
 		verify(this.session).write(any(InputStream.class), any());
 	}
 
+	@Test
+	public void testResource() throws IOException {
+		this.template.send(new GenericMessage<>(new ByteArrayResource("foo".getBytes())), FileExistsMode.IGNORE);
+		verify(this.session).write(any(InputStream.class), any());
+	}
+
 	@Test
 	public void testMissingFile() {
 		this.template.send(new GenericMessage<>(new File(UUID.randomUUID().toString())), FileExistsMode.IGNORE);

spring-integration-ftp/src/test/java/org/springframework/integration/ftp/config/FtpOutboundChannelAdapterParserTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2020 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.
@@ -17,12 +17,13 @@
 package org.springframework.integration.ftp.config;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 
+import java.nio.charset.StandardCharsets;
 import java.util.Iterator;
 import java.util.Set;
 
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
 
 import org.springframework.beans.factory.BeanCreationException;
 import org.springframework.beans.factory.annotation.Autowired;
@@ -45,18 +46,17 @@
 import org.springframework.messaging.MessageHandler;
 import org.springframework.messaging.support.GenericMessage;
 import org.springframework.test.annotation.DirtiesContext;
-import org.springframework.test.context.ContextConfiguration;
-import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+import org.springframework.test.context.junit.jupiter.SpringJUnitConfig;
 
 /**
  * @author Oleg Zhurakousky
  * @author Gary Russell
  * @author Gunnar Hillert
  * @author Artem Bilan
+ *
  * @since 2.0
  */
-@ContextConfiguration
-@RunWith(SpringJUnit4ClassRunner.class)
+@SpringJUnitConfig
 @DirtiesContext
 public class FtpOutboundChannelAdapterParserTests {
 
@@ -87,7 +87,7 @@ public class FtpOutboundChannelAdapterParserTests {
 	private FileNameGenerator fileNameGenerator;
 
 	@Test
-	public void testFtpOutboundChannelAdapterComplete() throws Exception {
+	public void testFtpOutboundChannelAdapterComplete() {
 		assertThat(TestUtils.getPropertyValue(ftpOutbound, "inputChannel")).isEqualTo(ftpChannel);
 		assertThat(ftpOutbound.getComponentName()).isEqualTo("ftpOutbound");
 		FileTransferringMessageHandler<?> handler =
@@ -100,7 +100,7 @@ public void testFtpOutboundChannelAdapterComplete() throws Exception {
 		assertThat(remoteFileSeparator).isEqualTo("");
 		assertThat(TestUtils.getPropertyValue(handler, "remoteFileTemplate.fileNameGenerator"))
 				.isEqualTo(this.fileNameGenerator);
-		assertThat(TestUtils.getPropertyValue(handler, "remoteFileTemplate.charset")).isEqualTo("UTF-8");
+		assertThat(TestUtils.getPropertyValue(handler, "remoteFileTemplate.charset")).isEqualTo(StandardCharsets.UTF_8);
 		assertThat(TestUtils.getPropertyValue(handler, "remoteFileTemplate.directoryExpressionProcessor")).isNotNull();
 		assertThat(TestUtils.getPropertyValue(handler, "remoteFileTemplate.temporaryDirectoryExpressionProcessor"))
 				.isNotNull();
@@ -122,9 +122,12 @@ public void testFtpOutboundChannelAdapterComplete() throws Exception {
 		assertThat(TestUtils.getPropertyValue(ftpOutbound, "handler.mode")).isEqualTo(FileExistsMode.APPEND);
 	}
 
-	@Test(expected = BeanCreationException.class)
-	public void testFailWithEmptyRfsAndAcdTrue() throws Exception {
-		new ClassPathXmlApplicationContext("FtpOutboundChannelAdapterParserTests-fail.xml", this.getClass()).close();
+	@Test
+	public void testFailWithEmptyRfsAndAcdTrue() {
+		assertThatExceptionOfType(BeanCreationException.class)
+				.isThrownBy(() ->
+						new ClassPathXmlApplicationContext("FtpOutboundChannelAdapterParserTests-fail.xml",
+								getClass()));
 	}
 
 	@Test
@@ -139,7 +142,7 @@ public void cachingByDefault() {
 	@Test
 	public void adviceChain() {
 		MessageHandler handler = TestUtils.getPropertyValue(advisedAdapter, "handler", MessageHandler.class);
-		handler.handleMessage(new GenericMessage<String>("foo"));
+		handler.handleMessage(new GenericMessage<>("foo"));
 		assertThat(adviceCalled).isEqualTo(1);
 	}
 
@@ -152,7 +155,7 @@ public void testTemporaryFileSuffix() {
 	}
 
 	@Test
-	public void testBeanExpressions() throws Exception {
+	public void testBeanExpressions() {
 		FileTransferringMessageHandler<?> handler =
 				TestUtils.getPropertyValue(withBeanExpressions, "handler", FileTransferringMessageHandler.class);
 		ExpressionEvaluatingMessageProcessor<?> dirExpProc = TestUtils.getPropertyValue(handler,