Add support for generating image previews.

Fix #387

Author: php-coder

.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;
 }