INT-3726-4.2.x: Support path for generateFileName

JIRA: https://jira.spring.io/browse/INT-3726

Backport for `4.2.x`

spring-integration-file/src/main/java/org/springframework/integration/file/FileWritingMessageHandler.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.
@@ -26,6 +26,7 @@ import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStreamWriter;
 import java.nio.charset.Charset;
+import java.util.regex.Matcher;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
@@ -259,6 +260,9 @@ public class FileWritingMessageHandler extends AbstractReplyProducingMessageHand
 			validateDestinationDirectory(directory, this.autoCreateDirectory);
 		}
 
+		Assert.state(!(this.temporaryFileSuffixSet && FileExistsMode.APPEND.equals(this.fileExistsMode)),
+				"'temporaryFileSuffix' can not be set when appending to an existing file");
+
 		if (!this.fileNameGeneratorSet && this.fileNameGenerator instanceof BeanFactoryAware) {
 			((BeanFactoryAware) this.fileNameGenerator).setBeanFactory(this.getBeanFactory());
 		}
@@ -277,9 +281,6 @@ public class FileWritingMessageHandler extends AbstractReplyProducingMessageHand
 				"Destination path [" + destinationDirectory + "] does not point to a directory.");
 		Assert.isTrue(destinationDirectory.canWrite(),
 				"Destination directory [" + destinationDirectory + "] is not writable.");
-		Assert.state(!(this.temporaryFileSuffixSet
-						&& FileExistsMode.APPEND.equals(this.fileExistsMode)),
-				"'temporaryFileSuffix' can not be set when appending to an existing file");
 	}
 
 	@Override
@@ -307,6 +308,11 @@ public class FileWritingMessageHandler extends AbstractReplyProducingMessageHand
 		if (!ignore) {
 
 			try {
+				if (!resultFile.exists() &&
+						generatedFileName.replaceAll("/", Matcher.quoteReplacement(File.separator))
+								.contains(File.separator)) {
+					resultFile.getParentFile().mkdirs();
+				}
 				if (payload instanceof File) {
 					resultFile = handleFileMessage((File) payload, tempFile, resultFile);
 				}

spring-integration-file/src/test/java/org/springframework/integration/file/FileWritingMessageHandlerTests.java

@@ -33,18 +33,19 @@ import java.io.FileInputStream;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
-import java.io.UnsupportedEncodingException;
 
 import org.junit.Before;
 import org.junit.Ignore;
 import org.junit.Rule;
 import org.junit.Test;
 import org.junit.rules.TemporaryFolder;
+
 import org.springframework.beans.factory.BeanFactory;
 import org.springframework.integration.channel.NullChannel;
 import org.springframework.integration.channel.QueueChannel;
 import org.springframework.integration.file.support.FileExistsMode;
 import org.springframework.integration.support.MessageBuilder;
+import org.springframework.integration.test.util.TestUtils;
 import org.springframework.messaging.Message;
 import org.springframework.messaging.MessageHandlingException;
 import org.springframework.messaging.support.GenericMessage;
@@ -57,6 +58,7 @@ import org.springframework.util.FileCopyUtils;
  * @author Gary Russell
  * @author Tony Falabella
  * @author Gunnar Hillert
+ * @author Artem Bilan
  */
 public class FileWritingMessageHandlerTests {
 
@@ -115,6 +117,21 @@ public class FileWritingMessageHandlerTests {
 		assertFileContentIsMatching(result);
 	}
 
+	@Test
+	public void testFileNameHeader() throws Exception {
+		Message<?> message = MessageBuilder.withPayload(SAMPLE_CONTENT)
+				.setHeader(FileHeaders.FILENAME, "dir1" + File.separator + "dir2/test")
+				.build();
+		QueueChannel output = new QueueChannel();
+		handler.setCharset(DEFAULT_ENCODING);
+		handler.setOutputChannel(output);
+		handler.handleMessage(message);
+		Message<?> result = output.receive(0);
+		assertFileContentIsMatching(result);
+		File destFile = (File) result.getPayload();
+		assertThat(destFile.getAbsolutePath(), containsString(TestUtils.applySystemFileSeparator("/dir1/dir2/test")));
+	}
+
 	@Test
 	public void stringPayloadCopiedToNewFileWithNewLines() throws Exception {
 		Message<?> message = MessageBuilder.withPayload(SAMPLE_CONTENT).build();
@@ -196,7 +213,8 @@ public class FileWritingMessageHandlerTests {
 		assertFileContentIs(result, SAMPLE_CONTENT + System.getProperty("line.separator"));
 	}
 
-	@Test @Ignore // INT-3289 ignored because it won't fail on all OS
+	@Test
+	@Ignore("INT-3289: doesn't fail on all OS")
 	public void testCreateDirFail() {
 		File dir = new File("/foo");
 		FileWritingMessageHandler handler = new FileWritingMessageHandler(dir);
@@ -404,18 +422,18 @@ public class FileWritingMessageHandlerTests {
 		assertFileContentIs(outFile, "foo");
 	}
 
-	void assertFileContentIsMatching(Message<?> result) throws IOException, UnsupportedEncodingException {
+	void assertFileContentIsMatching(Message<?> result) throws IOException {
 		assertFileContentIs(result, SAMPLE_CONTENT);
 	}
 
-	void assertFileContentIs(Message<?> result, String expected) throws IOException, UnsupportedEncodingException {
+	void assertFileContentIs(Message<?> result, String expected) throws IOException {
 		assertThat(result, is(notNullValue()));
 		assertThat(result.getPayload(), is(instanceOf(File.class)));
 		File destFile = (File) result.getPayload();
 		assertFileContentIs(destFile, expected);
 	}
 
-	void assertFileContentIs(File destFile, String expected) throws IOException, UnsupportedEncodingException {
+	void assertFileContentIs(File destFile, String expected) throws IOException {
 		assertNotSame(destFile, sourceFile);
 		assertThat(destFile.exists(), is(true));
 		byte[] destFileContent = FileCopyUtils.copyToByteArray(destFile);

src/reference/asciidoc/file.adoc

@@ -459,17 +459,22 @@ Once setup, the `DefaultFileNameGenerator` will employ the following resolution
 
 When using the XML namespace support, both, the _File Outbound Channel Adapter_ and the _File Outbound Gateway_ support the following two mutually exclusive configuration attributes:
 
-* `filename-generator` (a reference to a `FileNameGenerator`) implementation)
+* `filename-generator` (a reference to a `FileNameGenerator` implementation)
 * `filename-generator-expression` (an expression evaluating to a `String`)
 
-
-
 While writing files, a temporary file suffix will be used (default: `.writing`).
 It is appended to the filename while the file is being written.
 To customize the suffix, you can set the _temporary-file-suffix_ attribute on both the _File Outbound Channel Adapter_ and the _File Outbound Gateway_.
 
 NOTE: When using the _APPEND_ file _mode_, the _temporary-file-suffix_ attribute is ignored, since the data is appended to the file directly.
 
+Starting with _version 4.2.5_ the generated file name (as a result of `filename-generator`/`filename-generator-expression`
+evaluation) can represent a _sub-path_ together with the target file name.
+It is used as a second constructor argument for `File(File parent, String child)` as before, but in the past we didn't
+created (`mkdirs()`) directories for _sub-path_ assuming only the _file name_.
+This approach is useful for cases when we need to restore the file system tree according the source directory.
+For example we unzipping the archive and want to save all file in the target directory at the same order.
+
 [[file-writing-output-directory]]
 ==== Specifying the Output Directory
 
@@ -478,8 +483,6 @@ Both, the _File Outbound Channel Adapter_ and the _File Outbound Gateway_ provid
 * _directory_
 * _directory-expression_
 
-
-
 NOTE: The _directory-expression_ attribute is available since Spring Integration 2.2.
 
 *Using the directory attribute*