Refactoring of the ERS3UploadQueue and ERCloudFilesUploadQueue to sha…

…re the same implementation and avoid accidental death of the queue thread

The ERS3UploadQueue and ERCloudFilesUploadQueue are clearly duplicated. This commit introduces an abstract queue that handles all the logic to upload files asynchronously to a remote server. The upload process is unchanged. The queue logic was improved to perform all the upload logic (preparation + execution) inside of a try-catch block. This small change makes the queue much more robust by avoiding accidental death of the queue thread when an exception is thrown during the preparation phase.

Frameworks/BusinessLogic/ERAttachment/Sources/er/attachment/model/ERCloudFilesAttachment.java

@@ -9,6 +9,7 @@
 import com.rackspacecloud.client.cloudfiles.FilesClient;
 import com.webobjects.eocontrol.EOEditingContext;
 
+import er.attachment.upload.ERRemoteAttachment;
 import er.extensions.eof.ERXGenericRecord;
 import er.extensions.foundation.ERXProperties;
 
@@ -17,7 +18,7 @@
  * 
  * @author probert
  */
-public class ERCloudFilesAttachment extends _ERCloudFilesAttachment {
+public class ERCloudFilesAttachment extends _ERCloudFilesAttachment implements ERRemoteAttachment {
   @SuppressWarnings("unused")
   private static Logger log = Logger.getLogger(ERCloudFilesAttachment.class);
   public static final String STORAGE_TYPE = "cf";

Frameworks/BusinessLogic/ERAttachment/Sources/er/attachment/model/ERS3Attachment.java

@@ -8,6 +8,7 @@
 import com.amazon.s3.QueryStringAuthGenerator;
 import com.webobjects.eocontrol.EOEditingContext;
 
+import er.attachment.upload.ERRemoteAttachment;
 import er.extensions.eof.ERXGenericRecord;
 import er.extensions.foundation.ERXProperties;
 
@@ -24,7 +25,7 @@
  * 
  * @author mschrag
  */
-public class ERS3Attachment extends _ERS3Attachment {
+public class ERS3Attachment extends _ERS3Attachment implements ERRemoteAttachment {
 	/**
 	 * Do I need to update serialVersionUID?
 	 * See section 5.6 <cite>Type Changes Affecting Serialization</cite> on page 51 of the 

Frameworks/BusinessLogic/ERAttachment/Sources/er/attachment/processors/ERCloudFilesAttachmentProcessor.java

@@ -22,9 +22,7 @@
 
 import er.attachment.ERAttachmentRequestHandler;
 import er.attachment.model.ERCloudFilesAttachment;
-import er.extensions.concurrency.ERXAsyncQueue;
-import er.extensions.eof.ERXEC;
-import er.extensions.foundation.ERXExceptionUtilities;
+import er.attachment.upload.ERAttachmentUploadQueue;
 import er.extensions.foundation.ERXProperties;
 
 /**
@@ -49,7 +47,7 @@ public class ERCloudFilesAttachmentProcessor extends
 	private ERCloudFilesUploadQueue _queue;
 
 	public ERCloudFilesAttachmentProcessor() {
-		_queue = new ERCloudFilesUploadQueue();
+		_queue = new ERCloudFilesUploadQueue("ERCloudFilesAsyncQueue", this);
 		_queue.start();
 	}
 
@@ -232,115 +230,33 @@ public void performUpload(File uploadedFile, String originalFileName,
 
 	}
 
-	public class ERCloudFilesQueueEntry {
-		private File _uploadedFile;
-		private ERCloudFilesAttachment _attachment;
-
-		public ERCloudFilesQueueEntry(File uploadedFile, ERCloudFilesAttachment attachment) {
-			_uploadedFile = uploadedFile;
-			_attachment = attachment;
-		}
-
-		public File uploadedFile() {
-			return _uploadedFile;
+	public class ERCloudFilesUploadQueue extends ERAttachmentUploadQueue<ERCloudFilesAttachment> {
+		public ERCloudFilesUploadQueue(String name, ERAttachmentProcessor<ERCloudFilesAttachment> processor) {
+			super(name, processor);
 		}
 
-		public ERCloudFilesAttachment attachment() {
-			return _attachment;
-		}
-	}
-
-	public class ERCloudFilesUploadQueue extends ERXAsyncQueue<ERCloudFilesQueueEntry> {
-		private EOEditingContext _editingContext;
-
-		public ERCloudFilesUploadQueue() {
-			super("ERS3AsyncQueue");
-			_editingContext = ERXEC.newEditingContext();
-		}
+		@Override
+		protected void performUpload(ERCloudFilesAttachment attachment, File uploadedFile) throws Exception {
+			String bucket;
+			String key;
+			String mimeType;
+			String originalFileName = null;
 
-		public void enqueue(ERCloudFilesAttachment attachment) {
 			_editingContext.lock();
+
 			try {
-			  ERCloudFilesAttachment localAttachment = attachment
-						.localInstanceIn(_editingContext);
-				ERCloudFilesQueueEntry entry = new ERCloudFilesQueueEntry(
-						attachment._pendingUploadFile(), localAttachment);
-				enqueue(entry);
+				bucket = attachment.container();
+				key = attachment.key();
+				mimeType = attachment.mimeType();
+
+				if (proxyAsAttachment(attachment)) {
+					originalFileName = attachment.originalFileName();
+				}
 			} finally {
 				_editingContext.unlock();
 			}
-		}
 
-		@Override
-		public void process(ERCloudFilesQueueEntry object) {
-		  ERCloudFilesAttachment attachment = object.attachment();
-
-			File uploadedFile = object.uploadedFile();
-			if (uploadedFile != null && uploadedFile.exists()) {
-				String bucket;
-				String key;
-				String mimeType;
-				String configurationName;
-				String originalFileName = null;
-
-				_editingContext.lock();
-				try {
-					bucket = attachment.container();
-					key = attachment.key();
-					mimeType = attachment.mimeType();
-					configurationName = attachment.configurationName();
-					if (proxyAsAttachment(attachment)) {
-						originalFileName = attachment.originalFileName();
-					}
-				} finally {
-					_editingContext.unlock();
-				}
-
-				try {
-					performUpload(uploadedFile, originalFileName,
-									bucket, key, mimeType, attachment);
-
-					_editingContext.lock();
-					try {
-						attachment.setAvailable(Boolean.TRUE);
-						_editingContext.saveChanges();
-					} finally {
-						_editingContext.unlock();
-					}
-					if (delegate() != null) {
-						delegate()
-								.attachmentAvailable(
-										ERCloudFilesAttachmentProcessor.this,
-										attachment);
-					}
-				} catch (Throwable t) {
-					if (delegate() != null) {
-						delegate()
-								.attachmentNotAvailable(
-										ERCloudFilesAttachmentProcessor.this,
-										attachment,
-										ERXExceptionUtilities.toParagraph(t));
-					}
-					ERAttachmentProcessor.log.error("Failed to upload '"
-							+ uploadedFile + "' to CloudFiles.", t);
-				} finally {
-					if (attachment._isPendingDelete()) {
-						uploadedFile.delete();
-					}
-				}
-			} else {
-				if (delegate() != null) {
-					delegate()
-							.attachmentNotAvailable(
-									ERCloudFilesAttachmentProcessor.this,
-									attachment,
-									"Missing attachment file '" + uploadedFile
-											+ "'.");
-				}
-				ERAttachmentProcessor.log.error("Missing attachment file '"
-						+ uploadedFile + "'.");
-			}
+			((ERCloudFilesAttachmentProcessor)_processor).performUpload(uploadedFile, originalFileName, bucket, key, mimeType, attachment);
 		}
 	}
-
 }

Frameworks/BusinessLogic/ERAttachment/Sources/er/attachment/processors/ERS3AttachmentProcessor.java

@@ -24,9 +24,7 @@
 
 import er.attachment.ERAttachmentRequestHandler;
 import er.attachment.model.ERS3Attachment;
-import er.extensions.concurrency.ERXAsyncQueue;
-import er.extensions.eof.ERXEC;
-import er.extensions.foundation.ERXExceptionUtilities;
+import er.attachment.upload.ERAttachmentUploadQueue;
 import er.extensions.foundation.ERXProperties;
 
 /**
@@ -51,7 +49,7 @@ public class ERS3AttachmentProcessor extends
 	private ERS3UploadQueue _queue;
 
 	public ERS3AttachmentProcessor() {
-		_queue = new ERS3UploadQueue();
+		_queue = new ERS3UploadQueue("ERS3AsyncQueue", this);
 		_queue.start();
 	}
 
@@ -233,115 +231,31 @@ protected boolean failed(Response response) throws IOException {
 		return (responseCode < 200 || responseCode >= 300);
 	}
 
-	public class ERS3QueueEntry {
-		private File _uploadedFile;
-		private ERS3Attachment _attachment;
-
-		public ERS3QueueEntry(File uploadedFile, ERS3Attachment attachment) {
-			_uploadedFile = uploadedFile;
-			_attachment = attachment;
-		}
-
-		public File uploadedFile() {
-			return _uploadedFile;
+	public class ERS3UploadQueue extends ERAttachmentUploadQueue<ERS3Attachment> {
+		public ERS3UploadQueue(String name, ERAttachmentProcessor<ERS3Attachment> processor) {
+			super(name, processor);
 		}
 
-		public ERS3Attachment attachment() {
-			return _attachment;
-		}
-	}
-
-	public class ERS3UploadQueue extends ERXAsyncQueue<ERS3QueueEntry> {
-		private EOEditingContext _editingContext;
-
-		public ERS3UploadQueue() {
-			super("ERS3AsyncQueue");
-			_editingContext = ERXEC.newEditingContext();
-		}
+		@Override
+		protected void performUpload(ERS3Attachment attachment, File uploadedFile) throws Exception {
+			String bucket;
+			String key;
+			String mimeType;
+			String originalFileName = null;
 
-		public void enqueue(ERS3Attachment attachment) {
 			_editingContext.lock();
 			try {
-				ERS3Attachment localAttachment = attachment
-						.localInstanceIn(_editingContext);
-				ERS3QueueEntry entry = new ERS3QueueEntry(
-						attachment._pendingUploadFile(), localAttachment);
-				enqueue(entry);
+				bucket = attachment.bucket();
+				key = attachment.key();
+				mimeType = attachment.mimeType();
+				if (proxyAsAttachment(attachment)) {
+					originalFileName = attachment.originalFileName();
+				}
 			} finally {
 				_editingContext.unlock();
 			}
-		}
-
-		@Override
-		public void process(ERS3QueueEntry object) {
-			ERS3Attachment attachment = object.attachment();
-
-			File uploadedFile = object.uploadedFile();
-			if (uploadedFile != null && uploadedFile.exists()) {
-				String bucket;
-				String key;
-				String mimeType;
-				String configurationName;
-				String originalFileName = null;
-
-				_editingContext.lock();
-				try {
-					bucket = attachment.bucket();
-					key = attachment.key();
-					mimeType = attachment.mimeType();
-					configurationName = attachment.configurationName();
-					if (proxyAsAttachment(attachment)) {
-						originalFileName = attachment.originalFileName();
-					}
-				} finally {
-					_editingContext.unlock();
-				}
 
-				try {
-					performUpload(uploadedFile, originalFileName,
-									bucket, key, mimeType, attachment);
-
-					_editingContext.lock();
-					try {
-						attachment.setAvailable(Boolean.TRUE);
-						_editingContext.saveChanges();
-					} finally {
-						_editingContext.unlock();
-					}
-					if (delegate() != null) {
-						delegate()
-								.attachmentAvailable(
-										ERS3AttachmentProcessor.this,
-										attachment);
-					}
-				} catch (Throwable t) {
-					if (delegate() != null) {
-						delegate()
-								.attachmentNotAvailable(
-										ERS3AttachmentProcessor.this,
-										attachment,
-										ERXExceptionUtilities.toParagraph(t));
-					}
-					ERAttachmentProcessor.log.error("Failed to upload '"
-							+ uploadedFile + "' to S3.", t);
-				} finally {
-					if (attachment._isPendingDelete()) {
-						uploadedFile.delete();
-					}
-				}
-			} else {
-				if (delegate() != null) {
-					delegate()
-							.attachmentNotAvailable(
-									ERS3AttachmentProcessor.this,
-									attachment,
-									"Missing attachment file '" + uploadedFile
-											+ "'.");
-				}
-				ERAttachmentProcessor.log.error("Missing attachment file '"
-						+ uploadedFile + "'.");
-			}
+			((ERS3AttachmentProcessor) _processor).performUpload(uploadedFile, originalFileName, bucket, key, mimeType, attachment);
 		}
 	}
-
 }

Frameworks/BusinessLogic/ERAttachment/Sources/er/attachment/upload/ERAttachmentQueueEntry.java

@@ -0,0 +1,35 @@
+package er.attachment.upload;
+
+import java.io.File;
+
+import er.attachment.model.ERAttachment;
+
+/**
+ * The <code>ERAttachmentQueueEntry</code> is a wrapper that keeps a reference
+ * to the <code>ERAttachment</code> and the file being enqueued for uploading.
+ *
+ * @author <a href="mailto:[email protected]">Henrique Prange</a>
+ *
+ * @param <T>
+ *            the type of the attachment that can queued for uploading.
+ *
+ * @see ERRemoteAttachment
+ * @see ERAttachmentUploadQueue
+ */
+public class ERAttachmentQueueEntry<T extends ERAttachment & ERRemoteAttachment> {
+    private File _uploadedFile;
+    private T _attachment;
+
+    public ERAttachmentQueueEntry(File uploadedFile, T attachment) {
+        _uploadedFile = uploadedFile;
+        _attachment = attachment;
+    }
+
+    public File uploadedFile() {
+        return _uploadedFile;
+    }
+
+    public T attachment() {
+        return _attachment;
+    }
+}