the preview image of a link preview saved in cassandra is the one retrieved from the ftp storage

git-svn-id: https://svn.research-infrastructures.eu/d4science/gcube/trunk/portlets/user/share-updates@134212 82a268e6-3cf1-43bd-a215-b396298e98cf

src/main/java/org/gcube/portlets/user/shareupdates/server/ShareUpdateServiceImpl.java

@@ -1,6 +1,7 @@
 package org.gcube.portlets.user.shareupdates.server;
 
 import java.io.File;
+import java.io.FileOutputStream;
 import java.io.IOException;
 import java.net.HttpURLConnection;
 import java.net.MalformedURLException;
@@ -18,6 +19,7 @@ import java.util.UUID;
 
 import javax.net.ssl.HttpsURLConnection;
 
+import org.apache.commons.fileupload.util.Streams;
 import org.apache.commons.validator.routines.UrlValidator;
 import org.gcube.applicationsupportlayer.social.ApplicationNotificationsManager;
 import org.gcube.applicationsupportlayer.social.NotificationsManager;
@@ -82,15 +84,14 @@ public class ShareUpdateServiceImpl extends RemoteServiceServlet implements	Shar
 	private static final String STORAGE_OWNER = "gCubeSocialFramework";
 	public static final String UPLOAD_DIR = "/social-framework-uploads";
 	private static final String NEWS_FEED_PORTLET_CLASSNAME = "org.gcube.portlets.user.newsfeed.server.NewsServiceImpl";
+	private static String UPLOAD_LOCATION_LOCAL = System.getProperty("java.io.tmpdir");
 
 	/**
 	 * 
 	 */
 	private static Logger _log = LoggerFactory.getLogger(ShareUpdateServiceImpl.class);
-	/**
-	 * The Cassandra store interface
-	 */
 	private DatabookStore store;
+
 	/**
 	 * connect to cassandra at startup
 	 */
@@ -116,6 +117,7 @@ public class ShareUpdateServiceImpl extends RemoteServiceServlet implements	Shar
 			return false;
 		}			
 	}
+
 	/**
 	 * Share post that could contain a link preview.
 	 */
@@ -153,6 +155,8 @@ public class ShareUpdateServiceImpl extends RemoteServiceServlet implements	Shar
 		String url = preview.getUrl();
 		if (urlThumbnail == null)
 			urlThumbnail = "null";
+		else
+			urlThumbnail = saveThumbnailOnFTPAndGetUrl(urlThumbnail);
 
 		Date feedDate = new Date();
 
@@ -224,6 +228,77 @@ public class ShareUpdateServiceImpl extends RemoteServiceServlet implements	Shar
 
 	}
 
+	/**
+	 * Check if a resource at a given url exists or not. If it exists, create a file in the temp dir
+	 * of the tomcat
+	 * @param urlThumbnail
+	 * @return
+	 */
+	private File storeAndGetFile(String urlThumbnail){
+		try {
+			HttpURLConnection.setFollowRedirects(true);
+			HttpURLConnection con =
+					(HttpURLConnection) new URL(urlThumbnail).openConnection();
+			con.setRequestMethod("HEAD"); // body is not needed yet
+			if(con.getResponseCode() == HttpURLConnection.HTTP_OK){
+
+				//generate the random dir 
+				File theRandomDir = new File(UPLOAD_LOCATION_LOCAL + File.separator + UUID.randomUUID().toString());
+				theRandomDir.mkdir();
+				_log.debug("Created temp upload directory in: " + theRandomDir);
+
+				// generate a random file name and create it under the randomDir
+				File file = new File(theRandomDir, UUID.randomUUID().toString().substring(0, 10)); 
+
+				//Get the inputstream and copy there
+				URL url = new URL(urlThumbnail);
+				Streams.copy(url.openStream(), new FileOutputStream(file), true);
+				_log.debug("File is at " + file.getAbsolutePath());
+				return file;
+			}else
+				return null;
+		}
+		catch (Exception e) {
+			_log.error("The resource at url " + urlThumbnail + " doesn't exist");
+			return null;
+		}
+	}
+
+	/**
+	 * When a link preview needs to be saved, the method save the thumbnail on the storage no longer using the external url
+	 * @param urlThumbnail
+	 * @return the url of the thumbnail saved on the storage or null in case of error
+	 */
+	private String saveThumbnailOnFTPAndGetUrl(String urlThumbnail) {
+		File localFile;
+		if((localFile = storeAndGetFile(urlThumbnail)) != null){
+			String mimeType = null;
+			if (isWithinPortal()) {
+				try {
+					mimeType = FilePreviewer.getMimeType(localFile, localFile.getName());
+					String thumbnailUrlFTP = null;
+					switch(mimeType){
+					case "image/png":
+					case "image/gif":
+					case "image/tiff":
+					case "image/jpg":
+					case "image/jpeg":
+					case "image/bmp":
+						thumbnailUrlFTP = FilePreviewer.getImagePreview(localFile.getName(), localFile.getAbsolutePath(), null, mimeType).getImageUrls().get(0);
+						break;
+					default: break;
+					}
+					return thumbnailUrlFTP;
+				} catch (IOException e) {
+					_log.error("Error while saving thumbnail on ftp", e);
+				}
+			}
+		}else
+			_log.warn("the file at url " + urlThumbnail + " doesn't exist");
+		
+		return null;
+	}
+
 	/**
 	 * Share a post with at least one attachment.
 	 */
@@ -606,7 +681,7 @@ public class ShareUpdateServiceImpl extends RemoteServiceServlet implements	Shar
 			//smpURI = storageClient.getUrl(true).RFile(remoteFilePath); //"http://ciccio.com";
 			smpURI = storageClient.getHttpUrl(true).RFile(remoteFilePath);
 
-			//The storage uploader Thread starts here asyncronouslyù
+			//The storage uploader Thread starts here asyncronously
 			try {
 				mimeType = FilePreviewer.getMimeType(new File(fileabsolutePathOnServer), fileName);
 			} catch (IOException e) {