Support for download files as zip archive

vraptor-core/src/main/java/br/com/caelum/vraptor/observer/download/DownloadBuilder.java

@@ -6,6 +6,8 @@
 import java.io.File;
 import java.io.FileNotFoundException;
 import java.io.InputStream;
+import java.nio.file.Path;
+import java.util.List;
 
 import javax.enterprise.inject.Vetoed;
 
@@ -73,6 +75,23 @@ public static ByteArrayDownloadBuilder of(byte[] input) {
 		return new ByteArrayDownloadBuilder(input);
 	}
 
+	/**
+	 * Creates an instance for build a {@link ZipDownload}.<br>
+	 * 
+	 * <code>
+	 * 		List<Path> listOfFiles = [...];
+	 * 		Download download = DownloadBuilder.of(listOfFiles)
+	 * 			.withFileName("resume.zip")
+	 * 			.build();
+	 * </code>
+	 * 
+	 * @param files List of input files
+	 * @throws NullPointerException If the {@code input} argument is {@code null}
+	 */
+	public static ZipDownloadBuilder of(List<Path> files) {
+		return new ZipDownloadBuilder(files);
+	}
+
 	static abstract class AbstractDownloadBuilder<T> {
 		protected String fileName;
 		protected String contentType;
@@ -136,4 +155,16 @@ public ByteArrayDownload build() {
 			return new ByteArrayDownload(buff, contentType, fileName, doDownload);
 		}
 	}
-}
+
+	public static class ZipDownloadBuilder extends AbstractDownloadBuilder<ZipDownloadBuilder> {
+		private final List<Path> files;
+
+		ZipDownloadBuilder(List<Path> files) {
+			this.files = requireNonNull(files, "files can't be null");
+		}
+
+		public ZipDownload build() {
+			return new ZipDownload(fileName, files);
+		}
+	}
+}

vraptor-core/src/main/java/br/com/caelum/vraptor/observer/download/ZipDownload.java

@@ -0,0 +1,50 @@
+package br.com.caelum.vraptor.observer.download;
+
+import static java.nio.file.Files.copy;
+import static java.util.Arrays.asList;
+
+import java.io.IOException;
+import java.nio.file.Path;
+import java.util.zip.CRC32;
+import java.util.zip.CheckedOutputStream;
+import java.util.zip.ZipEntry;
+import java.util.zip.ZipOutputStream;
+
+import javax.servlet.http.HttpServletResponse;
+
+/**
+ * Supports multiple files download as a zip file.
+ * 
+ * @author Otávio Scherer Garcia
+ * @since 4.1
+ */
+public class ZipDownload implements Download {
+
+	private final String filename;
+	private final Iterable<Path> files;
+
+	public ZipDownload(String filename, Iterable<Path> files) {
+		this.filename = filename;
+		this.files = files;
+	}
+
+	public ZipDownload(String filename, Path... files) {
+		this(filename, asList(files));
+	}
+
+	@Override
+	public void write(HttpServletResponse response)
+		throws IOException {
+		response.setHeader("Content-disposition", "attachment; filename=" + filename);
+		response.setHeader("Content-type", "application/zip");
+
+		CheckedOutputStream stream = new CheckedOutputStream(response.getOutputStream(), new CRC32());
+		try (ZipOutputStream zip = new ZipOutputStream(stream)) {
+			for (Path file : files) {
+				zip.putNextEntry(new ZipEntry(file.getFileName().toString()));
+				copy(file, zip);
+				zip.closeEntry();
+			}
+		}
+	}
+}

vraptor-core/src/test/java/br/com/caelum/vraptor/observer/download/ByteArrayDownloadTest.java

@@ -20,7 +20,6 @@
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
-import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 
@@ -50,9 +49,9 @@ public void setUp() throws Exception {
 		MockitoAnnotations.initMocks(this);
 
 		bytes = new byte[] { (byte) 0x0 };
-		this.outputStream = new ByteArrayOutputStream();
+		outputStream = new ByteArrayOutputStream();
 
-		this.socketStream = new ServletOutputStream() {
+		socketStream = new ServletOutputStream() {
 			@Override
 			public void write(int b) throws IOException {
 				outputStream.write(b);

vraptor-core/src/test/java/br/com/caelum/vraptor/observer/download/FileDownloadTest.java

@@ -23,8 +23,8 @@
 import java.io.ByteArrayOutputStream;
 import java.io.File;
 import java.io.FileNotFoundException;
-import java.io.FileOutputStream;
 import java.io.IOException;
+import java.nio.file.Files;
 
 import javax.servlet.ServletOutputStream;
 import javax.servlet.WriteListener;
@@ -56,15 +56,12 @@ public class FileDownloadTest {
 	public void setUp() throws Exception {
 		MockitoAnnotations.initMocks(this);
 
-		bytes = new byte[] { (byte) 0 };
+		bytes = new byte[] { (byte) 0x0 };
 		outputStream = new ByteArrayOutputStream();
 
 		file = folder.newFile();
+		Files.write(file.toPath(), bytes);
 
-		try (FileOutputStream fileStream = new FileOutputStream(file)) {
-			fileStream.write(bytes);
-		}
-
 		socketStream = new ServletOutputStream() {
 			@Override
 			public void write(int b) throws IOException {

vraptor-core/src/test/java/br/com/caelum/vraptor/observer/download/InputStreamDownloadTest.java

@@ -52,11 +52,11 @@ public class InputStreamDownloadTest {
 	public void setUp() throws Exception {
 		MockitoAnnotations.initMocks(this);
 
-		bytes = new byte[] { (byte) 0 };
-		this.inputStream = new ByteArrayInputStream(bytes);
-		this.outputStream = new ByteArrayOutputStream();
+		bytes = new byte[] { (byte) 0x0 };
+		inputStream = new ByteArrayInputStream(bytes);
+		outputStream = new ByteArrayOutputStream();
 
-		this.socketStream = new ServletOutputStream() {
+		socketStream = new ServletOutputStream() {
 			@Override
 			public void write(int b) throws IOException {
 				outputStream.write(b);

vraptor-core/src/test/java/br/com/caelum/vraptor/observer/download/ZipDownloadTest.java

@@ -0,0 +1,78 @@
+/***
+ * Copyright (c) 2009 Caelum - www.caelum.com.br/opensource All rights reserved.
+ *
+ * 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 br.com.caelum.vraptor.observer.download;
+
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+import java.io.IOException;
+import java.nio.file.NoSuchFileException;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+
+import javax.servlet.ServletOutputStream;
+import javax.servlet.http.HttpServletResponse;
+
+import org.junit.Before;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.ExpectedException;
+import org.junit.rules.TemporaryFolder;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+
+public class ZipDownloadTest {
+
+	@Rule
+	public ExpectedException thrown = ExpectedException.none();
+
+	@Rule
+	public TemporaryFolder folder = new TemporaryFolder();
+
+	private Path inpuFile0;
+	private Path inpuFile1;
+
+	private @Mock HttpServletResponse response;
+	private @Mock ServletOutputStream socketStream;
+
+	@Before
+	public void setUp() throws Exception {
+		MockitoAnnotations.initMocks(this);
+
+		inpuFile0 = folder.newFile().toPath();
+		inpuFile1 = folder.newFile().toPath();
+
+		when(response.getOutputStream()).thenReturn(socketStream);
+	}
+
+	@Test
+	public void builderShouldThrowsExceptionIfFileDoesntExists() throws Exception {
+		thrown.expect(NoSuchFileException.class);
+
+		Download download = new ZipDownload("file.zip", Paths.get("/path/that/doesnt/exists/picture.jpg"));
+		download.write(response);
+	}
+
+	@Test
+	public void shouldUseHeadersToHttpResponse() throws IOException {
+		Download fd = new ZipDownload("download.zip", inpuFile0, inpuFile1);
+		fd.write(response);
+
+		verify(response, times(1)).setHeader("Content-type", "application/zip");
+		verify(response, times(1)).setHeader("Content-disposition", "attachment; filename=download.zip");
+	}
+}

vraptor-site/content/en/docs/download-and-upload.html

@@ -59,6 +59,18 @@
 }
 ~~~
 
+You can also put a list of files to download, so will sent to the browser compressed as Zip archive.
+
+~~~ 
+#!java
+public Download pictures() {
+	Path pic01 = new File("/path/to/the/pic01.jpg").toPath();
+	Path pic02 = new File("/path/to/the/pic02.jpg").toPath();
+	return new ZipDownload("pics.zip", pic01, pic02);
+}
+~~~
+
+
 ##Using DownloadBuilder
 
 `DownloadBuilder` is a class to help you to create instances for `Download`, using a fluent interface. To create a `FileDownload` you can write this code:

vraptor-site/content/pt/docs/download-e-upload.html

@@ -27,7 +27,7 @@
 @Controller
 public class PerfilController {
 	public Download foto(Perfil perfil) {
-		File file = new File("/path/para/a/foto." + perfil.getId()+ ".jpg");
+		File file = new File("/caminho/para/a/foto." + perfil.getId()+ ".jpg");
 		String contentType = "image/jpg";
 		String filename = perfil.getNome() + ".jpg";
 
@@ -60,6 +60,19 @@
 }
 ~~~
 
+Você também pode enviar uma lista de arquivos para download, e desta forma eles serão enviados ao browser 
+comprimidos em um arquivo Zip.
+
+~~~ 
+#!java
+public Download fotos() {
+	Path foto01 = new File("/caminho/para/a/foto01.jpg").toPath();
+	Path foto02 = new File("/caminho/para/a/foto02.jpg").toPath();
+	return new ZipDownload("fotos.zip", foto01, foto02);
+}
+~~~
+
+
 ##Using DownloadBuilder
 
 `DownloadBuilder` é uma classe útil para ajudar você a criar instâncias da classe `Download`, usando uma interface fluente. Para criar uma instância de um `FileDownload` você pode escrever o seguinte código: