Generate preview for images

.travis.yml

@@ -11,7 +11,7 @@ env:
 before_script:
   - if [ "$SPRING_PROFILES_ACTIVE" = 'travis' ]; then
       mysql -u travis -e 'CREATE DATABASE mystamps CHARACTER SET utf8;';
-      mkdir -p /tmp/uploads;
+      mkdir -p /tmp/uploads /tmp/preview;
       if [ "$TRAVIS_BRANCH" = 'prod' ]; then
         pip install --user ansible==2.1.1.0;
       fi;

NEWS.txt

@@ -13,6 +13,7 @@
 - (functionality)  add possibility for adding series sales
 - (functionality)  add interface for viewing series sales (contributed by Sergey Chechenev)
 - (functionality)  name of category/country in Russian now are optional fields
+- (functionality)  preview now is generated after uploading an image
 
 0.3
 - (functionality)  implemented possibility to user to add series to his collection

docker/Dockerfile

@@ -16,12 +16,12 @@ ENV SPRING_PROFILES_ACTIVE=test
 # See also: https://docs.docker.com/engine/reference/builder/#run
 RUN mkdir /data \
  && useradd mystamps --home-dir /data/mystamps --create-home --comment 'MyStamps' \
- && mkdir /data/uploads /data/heap-dumps \
- && chown mystamps:mystamps /data/uploads /data/heap-dumps
+ && mkdir /data/uploads /data/preview /data/heap-dumps \
+ && chown mystamps:mystamps /data/uploads /data/preview /data/heap-dumps
 
 # Creates mount points and marks them as holding externally mounted volumes from native host.
 # See also: https://docs.docker.com/engine/reference/builder/#volume
-VOLUME /data/uploads /data/heap-dumps
+VOLUME /data/uploads /data/preview /data/heap-dumps
 
 # Sets the user name to use when running the image and for any subsequent RUN, CMD and ENTRYPOINT instructions.
 # See also: https://docs.docker.com/engine/reference/builder/#user

pom.xml

@@ -22,6 +22,12 @@
 			<version>${javax.validation.version}</version>
 		</dependency>
 
+		<dependency>
+			<groupId>net.coobird</groupId>
+			<artifactId>thumbnailator</artifactId>
+			<version>${thumbnailator.version}</version>
+		</dependency>
+
 		<dependency>
 			<groupId>org.apache.commons</groupId>
 			<artifactId>commons-lang3</artifactId>
@@ -521,6 +527,7 @@
 		<subethasmtp.version>3.1.7</subethasmtp.version>
 		<surefire.plugin.version>2.19.1</surefire.plugin.version>
 		<testng.version>6.8.8</testng.version>
+		<thumbnailator.version>0.4.8</thumbnailator.version>
 
 		<!-- Redefine default value from spring-boot-dependencies (https://github.com/spring-projects/spring-boot/blob/v1.4.6.RELEASE/spring-boot-dependencies/pom.xml) -->
 		<thymeleaf-extras-springsecurity4.version>3.0.2.RELEASE</thymeleaf-extras-springsecurity4.version>

src/main/java/ru/mystamps/web/Url.java

@@ -64,7 +64,8 @@ public final class Url {
 
 	public static final String INFO_COLLECTION_PAGE  = "/collection/{slug}";
 
-	public static final String GET_IMAGE_PAGE        = "/image/{id}";
+	public static final String GET_IMAGE_PAGE         = "/image/{id}";
+	public static final String GET_IMAGE_PREVIEW_PAGE = "/image/preview/{id}";
 
 	public static final String FORBIDDEN_PAGE        = "/error/403";
 	public static final String NOT_FOUND_PAGE        = "/error/404";
@@ -145,6 +146,7 @@ public static Map<String, String> asMap(boolean serveContentFromSingleHost) {
 			map.put("SELECTIZE_CSS", SELECTIZE_CSS);
 			map.put("SELECTIZE_JS", SELECTIZE_JS);
 			map.put("GET_IMAGE_PAGE", GET_IMAGE_PAGE);
+			map.put("GET_IMAGE_PREVIEW_PAGE", GET_IMAGE_PREVIEW_PAGE);
 			map.put("FAVICON_ICO", FAVICON_ICO);
 			map.put("MAIN_CSS", MAIN_CSS);
 			map.put("CATALOG_UTILS_JS", CATALOG_UTILS_JS);
@@ -153,6 +155,7 @@ public static Map<String, String> asMap(boolean serveContentFromSingleHost) {
 		} else {
 			// Use separate domain for our own resources
 			map.put("GET_IMAGE_PAGE", STATIC_RESOURCES_URL + GET_IMAGE_PAGE);
+			map.put("GET_IMAGE_PREVIEW_PAGE", STATIC_RESOURCES_URL + GET_IMAGE_PREVIEW_PAGE);
 			map.put("FAVICON_ICO", STATIC_RESOURCES_URL + FAVICON_ICO);
 			map.put("MAIN_CSS", STATIC_RESOURCES_URL + MAIN_CSS);
 			map.put("CATALOG_UTILS_JS", STATIC_RESOURCES_URL + CATALOG_UTILS_JS);

src/main/java/ru/mystamps/web/config/ServicesConfig.java

@@ -80,6 +80,7 @@ public CronService getCronService() {
 	public ImageService getImageService() {
 		return new ImageServiceImpl(
 			strategiesConfig.getImagePersistenceStrategy(),
+			new TimedImagePreviewStrategy(new ThumbnailatorImagePreviewStrategy()),
 			daoConfig.getImageDao()
 		);
 	}

src/main/java/ru/mystamps/web/config/StrategiesConfig.java

@@ -57,7 +57,8 @@ class FsStrategiesConfig implements StrategiesConfig {
 		@Override
 		public ImagePersistenceStrategy getImagePersistenceStrategy() {
 			return new FilesystemImagePersistenceStrategy(
-				env.getRequiredProperty("app.upload.dir")
+				env.getRequiredProperty("app.upload.dir"),
+				env.getRequiredProperty("app.preview.dir")
 			);
 		}
 

src/main/java/ru/mystamps/web/controller/ImageController.java

@@ -60,5 +60,27 @@ public void getImage(@PathVariable("id") Integer imageId, HttpServletResponse re
 		response.getOutputStream().write(image.getData());
 	}
 
+	@GetMapping(Url.GET_IMAGE_PREVIEW_PAGE)
+	public void getImagePreview(@PathVariable("id") Integer imageId, HttpServletResponse response)
+		throws IOException {
+
+		if (imageId == null) {
+			response.sendError(HttpServletResponse.SC_NOT_FOUND);
+			return;
+		}
+
+		ImageDto image = imageService.getOrCreatePreview(imageId);
+		if (image == null) {
+			// return original image when error has occurred
+			getImage(imageId, response);
+			return;
+		}
+
+		response.setContentType("image/" + image.getType().toLowerCase(Locale.ENGLISH));
+		response.setContentLength(image.getData().length);
+
+		response.getOutputStream().write(image.getData());
+	}
+
 }
 

src/main/java/ru/mystamps/web/dao/ImageDataDao.java

@@ -21,6 +21,6 @@
 import ru.mystamps.web.dao.dto.DbImageDto;
 
 public interface ImageDataDao {
-	DbImageDto findByImageId(Integer imageId);
+	DbImageDto findByImageId(Integer imageId, boolean preview);
 	Integer add(AddImageDataDbDto imageData);
 }

src/main/java/ru/mystamps/web/dao/dto/AddImageDataDbDto.java

@@ -25,4 +25,5 @@
 public class AddImageDataDbDto {
 	private Integer imageId;
 	private byte[] content;
+	private boolean preview;
 }

src/main/java/ru/mystamps/web/dao/impl/JdbcImageDataDao.java

@@ -17,7 +17,6 @@
  */
 package ru.mystamps.web.dao.impl;
 
-import java.util.Collections;
 import java.util.HashMap;
 import java.util.Map;
 
@@ -48,11 +47,15 @@ public class JdbcImageDataDao implements ImageDataDao {
 	private String addImageDataSql;
 
 	@Override
-	public DbImageDto findByImageId(Integer imageId) {
+	public DbImageDto findByImageId(Integer imageId, boolean preview) {
+		Map<String, Object> params = new HashMap<>();
+		params.put("image_id", imageId);
+		params.put("preview", preview);
+
 		try {
 			return jdbcTemplate.queryForObject(
 				findByImageIdSql,
-				Collections.singletonMap("image_id", imageId),
+				params,
 				RowMappers::forDbImageDto
 			);
 		} catch (EmptyResultDataAccessException ignored) {
@@ -65,6 +68,7 @@ public Integer add(AddImageDataDbDto imageData) {
 		Map<String, Object> params = new HashMap<>();
 		params.put("image_id", imageData.getImageId());
 		params.put("content", imageData.getContent());
+		params.put("preview", imageData.isPreview());
 
 		KeyHolder holder = new GeneratedKeyHolder();
 

src/main/java/ru/mystamps/web/service/DatabaseImagePersistenceStrategy.java

@@ -53,6 +53,7 @@ public void save(MultipartFile file, ImageInfoDto image) {
 			AddImageDataDbDto imageData = new AddImageDataDbDto();
 			imageData.setImageId(image.getId());
 			imageData.setContent(file.getBytes());
+			imageData.setPreview(false);
 
 			Integer id = imageDataDao.add(imageData);
 			LOG.info("Image #{}: meta data has been saved to #{}", image.getId(), id);
@@ -63,9 +64,21 @@ public void save(MultipartFile file, ImageInfoDto image) {
 		}
 	}
 
+	@Override
+	public void savePreview(byte[] data, ImageInfoDto image) {
+		AddImageDataDbDto imageData = new AddImageDataDbDto();
+		imageData.setImageId(image.getId());
+		imageData.setContent(data);
+		imageData.setPreview(true);
+
+		imageDataDao.add(imageData);
+
+		LOG.info("Image #{}: preview has been saved", image.getId());
+	}
+
 	@Override
 	public ImageDto get(ImageInfoDto image) {
-		DbImageDto imageDto = imageDataDao.findByImageId(image.getId());
+		DbImageDto imageDto = imageDataDao.findByImageId(image.getId(), false);
 		if (imageDto == null) {
 			LOG.warn("Image #{}: content not found", image.getId());
 			return null;
@@ -74,4 +87,15 @@ public ImageDto get(ImageInfoDto image) {
 		return imageDto;
 	}
 
+	@Override
+	public ImageDto getPreview(ImageInfoDto image) {
+		DbImageDto imageDto = imageDataDao.findByImageId(image.getId(), true);
+		if (imageDto == null) {
+			LOG.info("Image #{}: preview not found", image.getId());
+			return null;
+		}
+
+		return imageDto;
+	}
+
 }

src/main/java/ru/mystamps/web/service/FilesystemImagePersistenceStrategy.java

@@ -40,9 +40,11 @@ public class FilesystemImagePersistenceStrategy implements ImagePersistenceStrat
 		LoggerFactory.getLogger(FilesystemImagePersistenceStrategy.class);
 
 	private final File storageDir;
+	private final File previewDir;
 
-	public FilesystemImagePersistenceStrategy(String storageDir) {
+	public FilesystemImagePersistenceStrategy(String storageDir, String previewDir) {
 		this.storageDir = new File(storageDir);
+		this.previewDir = new File(previewDir);
 	}
 
 	@PostConstruct
@@ -54,11 +56,29 @@ public void init() {
 
 		} else if (!storageDir.canWrite()) {
 			LOG.warn(
+				// TODO(java9): log also user: ProcessHandle.current().info().user()
 				"Directory '{}' exists but isn't writable for the current user! "
 				+ "Image uploading won't work.",
 				storageDir
 			);
 		}
+
+		LOG.info("Image previews will be saved into {} directory", previewDir);
+
+		if (!previewDir.exists()) { // NOPMD: ConfusingTernary (it's ok for me)
+			LOG.warn(
+				"Directory '{}' doesn't exist! Image preview generation won't work",
+				previewDir
+			);
+
+		} else if (!previewDir.canWrite()) {
+			// TODO(java9): log also user: ProcessHandle.current().info().user()
+			LOG.warn(
+				"Directory '{}' exists but isn't writable for the current user! "
+				+ "Image preview generation won't work",
+				previewDir
+			);
+		}
 	}
 
 	@Override
@@ -74,9 +94,27 @@ public void save(MultipartFile file, ImageInfoDto image) {
 		}
 	}
 
+	@Override
+	public void savePreview(byte[] data, ImageInfoDto image) {
+		try {
+			Path dest = generateFilePath(previewDir, image);
+			writeToFile(data, dest);
+
+			LOG.info("Image preview data has been written into file {}", dest);
+
+		} catch (IOException ex) {
+			throw new ImagePersistenceException(ex);
+		}
+	}
+
 	@Override
 	public ImageDto get(ImageInfoDto image) {
-		return get(storageDir, image);
+		return get(storageDir, image, true);
+	}
+
+	@Override
+	public ImageDto getPreview(ImageInfoDto image) {
+		return get(previewDir, image, false);
 	}
 
 	// protected to allow spying
@@ -93,6 +131,11 @@ protected void writeToFile(MultipartFile file, Path dest) throws IOException {
 		Files.copy(file.getInputStream(), dest);
 	}
 
+	// protected to allow spying
+	protected void writeToFile(byte[] data, Path dest) throws IOException {
+		Files.write(dest, data);
+	}
+
 	// protected to allow spying
 	protected boolean exists(Path path) {
 		return Files.exists(path);
@@ -103,10 +146,16 @@ protected byte[] toByteArray(Path dest) throws IOException {
 		return Files.readAllBytes(dest);
 	}
 
-	private ImageDto get(File dir, ImageInfoDto image) {
+	private ImageDto get(File dir, ImageInfoDto image, boolean logWarning) {
 		Path dest = generateFilePath(dir, image);
 		if (!exists(dest)) {
-			LOG.warn("Found image without content: #{} ({} doesn't exist)", image.getId(), dest);
+			if (logWarning) {
+				LOG.warn(
+					"Image #{}: content not found ({} doesn't exist)",
+					image.getId(),
+					dest
+				);
+			}
 			return null;
 		}
 

src/main/java/ru/mystamps/web/service/ImagePersistenceStrategy.java

@@ -24,5 +24,7 @@
 
 public interface ImagePersistenceStrategy {
 	void save(MultipartFile file, ImageInfoDto image);
+	void savePreview(byte[] data, ImageInfoDto image);
 	ImageDto get(ImageInfoDto image);
+	ImageDto getPreview(ImageInfoDto image);
 }

src/main/java/ru/mystamps/web/service/ImagePreviewStrategy.java

@@ -0,0 +1,22 @@
+/*
+ * Copyright (C) 2009-2017 Slava Semushin <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+package ru.mystamps.web.service;
+
+public interface ImagePreviewStrategy {
+	byte[] createPreview(byte[] image);
+}

src/main/java/ru/mystamps/web/service/ImageService.java

@@ -26,6 +26,7 @@
 public interface ImageService {
 	Integer save(MultipartFile file);
 	ImageDto get(Integer imageId);
+	ImageDto getOrCreatePreview(Integer imageId);
 	void addToSeries(Integer seriesId, Integer imageId);
 	List<Integer> findBySeriesId(Integer seriesId);
 }