001 /**
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements. See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License. You may obtain a copy of the License at
008 *
009 * http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017 package org.apache.camel.component.mail;
018
019 import java.util.Enumeration;
020 import java.util.LinkedList;
021 import java.util.Queue;
022 import java.util.UUID;
023 import javax.mail.Flags;
024 import javax.mail.Folder;
025 import javax.mail.FolderNotFoundException;
026 import javax.mail.Header;
027 import javax.mail.Message;
028 import javax.mail.MessagingException;
029 import javax.mail.Store;
030 import javax.mail.search.FlagTerm;
031
032 import org.apache.camel.BatchConsumer;
033 import org.apache.camel.Exchange;
034 import org.apache.camel.Processor;
035 import org.apache.camel.ShutdownRunningTask;
036 import org.apache.camel.impl.ScheduledPollConsumer;
037 import org.apache.camel.spi.ShutdownAware;
038 import org.apache.camel.spi.Synchronization;
039 import org.apache.camel.util.CastUtils;
040 import org.apache.camel.util.ObjectHelper;
041 import org.slf4j.Logger;
042 import org.slf4j.LoggerFactory;
043 import org.springframework.mail.javamail.JavaMailSenderImpl;
044
045 /**
046 * A {@link org.apache.camel.Consumer Consumer} which consumes messages from JavaMail using a
047 * {@link javax.mail.Transport Transport} and dispatches them to the {@link Processor}
048 */
049 public class MailConsumer extends ScheduledPollConsumer implements BatchConsumer, ShutdownAware {
050 public static final String POP3_UID = "CamelPop3Uid";
051 public static final long DEFAULT_CONSUMER_DELAY = 60 * 1000L;
052 private static final transient Logger LOG = LoggerFactory.getLogger(MailConsumer.class);
053
054 private final JavaMailSenderImpl sender;
055 private Folder folder;
056 private Store store;
057 private int maxMessagesPerPoll;
058 private volatile ShutdownRunningTask shutdownRunningTask;
059 private volatile int pendingExchanges;
060
061 public MailConsumer(MailEndpoint endpoint, Processor processor, JavaMailSenderImpl sender) {
062 super(endpoint, processor);
063 this.sender = sender;
064 }
065
066 @Override
067 protected void doStart() throws Exception {
068 super.doStart();
069 }
070
071 @Override
072 protected void doStop() throws Exception {
073 if (folder != null && folder.isOpen()) {
074 folder.close(true);
075 }
076 if (store != null && store.isConnected()) {
077 store.close();
078 }
079
080 super.doStop();
081 }
082
083 protected int poll() throws Exception {
084 // must reset for each poll
085 shutdownRunningTask = null;
086 pendingExchanges = 0;
087 int polledMessages = 0;
088
089 ensureIsConnected();
090
091 if (store == null || folder == null) {
092 throw new IllegalStateException("MailConsumer did not connect properly to the MailStore: "
093 + getEndpoint().getConfiguration().getMailStoreLogInformation());
094 }
095
096 if (LOG.isDebugEnabled()) {
097 LOG.debug("Polling mailfolder: " + getEndpoint().getConfiguration().getMailStoreLogInformation());
098 }
099
100 if (getEndpoint().getConfiguration().getFetchSize() == 0) {
101 LOG.warn("Fetch size is 0 meaning the configuration is set to poll no new messages at all. Camel will skip this poll.");
102 return 0;
103 }
104
105 // ensure folder is open
106 if (!folder.isOpen()) {
107 folder.open(Folder.READ_WRITE);
108 }
109
110 try {
111 int count = folder.getMessageCount();
112 if (count > 0) {
113 Message[] messages;
114
115 // should we process all messages or only unseen messages
116 if (getEndpoint().getConfiguration().isUnseen()) {
117 messages = folder.search(new FlagTerm(new Flags(Flags.Flag.SEEN), false));
118 } else {
119 messages = folder.getMessages();
120 }
121
122 polledMessages = processBatch(CastUtils.cast(createExchanges(messages)));
123 } else if (count == -1) {
124 throw new MessagingException("Folder: " + folder.getFullName() + " is closed");
125 }
126 } catch (Exception e) {
127 handleException(e);
128 } finally {
129 // need to ensure we release resources
130 try {
131 if (folder.isOpen()) {
132 folder.close(true);
133 }
134 } catch (Exception e) {
135 // some mail servers will lock the folder so we ignore in this case (CAMEL-1263)
136 LOG.debug("Could not close mailbox folder: " + folder.getName(), e);
137 }
138 }
139
140 return polledMessages;
141 }
142
143 public void setMaxMessagesPerPoll(int maxMessagesPerPoll) {
144 this.maxMessagesPerPoll = maxMessagesPerPoll;
145 }
146
147 public int processBatch(Queue<Object> exchanges) throws Exception {
148 int total = exchanges.size();
149
150 // limit if needed
151 if (maxMessagesPerPoll > 0 && total > maxMessagesPerPoll) {
152 if (LOG.isDebugEnabled()) {
153 LOG.debug("Limiting to maximum messages to poll " + maxMessagesPerPoll + " as there was " + total + " messages in this poll.");
154 }
155 total = maxMessagesPerPoll;
156 }
157
158 for (int index = 0; index < total && isBatchAllowed(); index++) {
159 // only loop if we are started (allowed to run)
160 Exchange exchange = ObjectHelper.cast(Exchange.class, exchanges.poll());
161 // add current index and total as properties
162 exchange.setProperty(Exchange.BATCH_INDEX, index);
163 exchange.setProperty(Exchange.BATCH_SIZE, total);
164 exchange.setProperty(Exchange.BATCH_COMPLETE, index == total - 1);
165
166 // update pending number of exchanges
167 pendingExchanges = total - index - 1;
168
169 // must use the original message in case we need to workaround a charset issue when extracting mail content
170 final Message mail = exchange.getIn(MailMessage.class).getOriginalMessage();
171
172 // add on completion to handle after work when the exchange is done
173 exchange.addOnCompletion(new Synchronization() {
174 public void onComplete(Exchange exchange) {
175 processCommit(mail, exchange);
176 }
177
178 public void onFailure(Exchange exchange) {
179 processRollback(mail, exchange);
180 }
181
182 @Override
183 public String toString() {
184 return "MailConsumerOnCompletion";
185 }
186 });
187
188 // process the exchange
189 processExchange(exchange);
190 }
191
192 return total;
193 }
194
195 public boolean deferShutdown(ShutdownRunningTask shutdownRunningTask) {
196 // store a reference what to do in case when shutting down and we have pending messages
197 this.shutdownRunningTask = shutdownRunningTask;
198 // do not defer shutdown
199 return false;
200 }
201
202 public int getPendingExchangesSize() {
203 // only return the real pending size in case we are configured to complete all tasks
204 if (ShutdownRunningTask.CompleteAllTasks == shutdownRunningTask) {
205 return pendingExchanges;
206 } else {
207 return 0;
208 }
209 }
210
211 public void prepareShutdown() {
212 // noop
213 }
214
215 public boolean isBatchAllowed() {
216 // stop if we are not running
217 boolean answer = isRunAllowed();
218 if (!answer) {
219 return false;
220 }
221
222 if (shutdownRunningTask == null) {
223 // we are not shutting down so continue to run
224 return true;
225 }
226
227 // we are shutting down so only continue if we are configured to complete all tasks
228 return ShutdownRunningTask.CompleteAllTasks == shutdownRunningTask;
229 }
230
231 protected Queue<Exchange> createExchanges(Message[] messages) throws MessagingException {
232 Queue<Exchange> answer = new LinkedList<Exchange>();
233
234 int fetchSize = getEndpoint().getConfiguration().getFetchSize();
235 int count = fetchSize == -1 ? messages.length : Math.min(fetchSize, messages.length);
236
237 if (LOG.isDebugEnabled()) {
238 LOG.debug("Fetching " + count + " messages. Total " + messages.length + " messages.");
239 }
240
241 for (int i = 0; i < count; i++) {
242 Message message = messages[i];
243 if (!message.getFlags().contains(Flags.Flag.DELETED)) {
244 Exchange exchange = getEndpoint().createExchange(message);
245
246 // If the protocol is POP3 we need to remember the uid on the exchange
247 // so we can find the mail message again later to be able to delete it
248 if (getEndpoint().getConfiguration().getProtocol().startsWith("pop3")) {
249 String uid = generatePop3Uid(message);
250 if (uid != null) {
251 exchange.setProperty(POP3_UID, uid);
252 LOG.trace("POP3 mail message using uid {}", uid);
253 }
254 }
255 answer.add(exchange);
256 } else {
257 if (LOG.isDebugEnabled()) {
258 LOG.debug("Skipping message as it was flagged as deleted: " + MailUtils.dumpMessage(message));
259 }
260 }
261 }
262
263 return answer;
264 }
265
266 /**
267 * Strategy to process the mail message.
268 */
269 protected void processExchange(Exchange exchange) throws Exception {
270 if (LOG.isDebugEnabled()) {
271 MailMessage msg = (MailMessage) exchange.getIn();
272 LOG.debug("Processing message: " + MailUtils.dumpMessage(msg.getMessage()));
273 }
274 getProcessor().process(exchange);
275 }
276
277 /**
278 * Strategy to flag the message after being processed.
279 *
280 * @param mail the mail message
281 * @param exchange the exchange
282 */
283 protected void processCommit(Message mail, Exchange exchange) {
284 try {
285 // ensure folder is open
286 if (!folder.isOpen()) {
287 folder.open(Folder.READ_WRITE);
288 }
289
290 // If the protocol is POP3, the message needs to be synced with the folder via the UID.
291 // Otherwise setting the DELETE/SEEN flag won't delete the message.
292 String uid = (String) exchange.removeProperty(POP3_UID);
293 if (uid != null) {
294 int count = folder.getMessageCount();
295 Message found = null;
296 LOG.trace("Looking for POP3Message with UID {} from folder with {} mails", uid, count);
297 for (int i = 1; i <= count; ++i) {
298 Message msg = folder.getMessage(i);
299 if (uid.equals(generatePop3Uid(msg))) {
300 LOG.debug("Found POP3Message with UID {} from folder with {} mails", uid, count);
301 found = msg;
302 break;
303 }
304 }
305
306 if (found == null) {
307 boolean delete = getEndpoint().getConfiguration().isDelete();
308 LOG.warn("POP3message not found in folder. Message cannot be marked as " + (delete ? "DELETED" : "SEEN"));
309 } else {
310 mail = found;
311 }
312 }
313
314 if (getEndpoint().getConfiguration().isDelete()) {
315 LOG.trace("Exchange processed, so flagging message as DELETED");
316 mail.setFlag(Flags.Flag.DELETED, true);
317 } else {
318 LOG.trace("Exchange processed, so flagging message as SEEN");
319 mail.setFlag(Flags.Flag.SEEN, true);
320 }
321 } catch (MessagingException e) {
322 LOG.warn("Error occurred during flagging message as DELETED/SEEN", e);
323 exchange.setException(e);
324 }
325 }
326
327 /**
328 * Strategy when processing the exchange failed.
329 *
330 * @param mail the mail message
331 * @param exchange the exchange
332 */
333 protected void processRollback(Message mail, Exchange exchange) {
334 Exception cause = exchange.getException();
335 if (cause != null) {
336 LOG.warn("Exchange failed, so rolling back message status: " + exchange, cause);
337 } else {
338 LOG.warn("Exchange failed, so rolling back message status: " + exchange);
339 }
340 }
341
342 /**
343 * Generates an UID of the POP3Message
344 *
345 * @param message the POP3Message
346 * @return the generated uid
347 */
348 protected String generatePop3Uid(Message message) {
349 String uid = null;
350
351 // create an UID based on message headers on the POP3Message, that ought to be unique
352 StringBuilder buffer = new StringBuilder();
353 try {
354 Enumeration it = message.getAllHeaders();
355 while (it.hasMoreElements()) {
356 Header header = (Header) it.nextElement();
357 buffer.append(header.getName())
358 .append("=")
359 .append(header.getValue())
360 .append("\n");
361 }
362 if (buffer.length() > 0) {
363 LOG.debug("Generating UID from the following:\n" + buffer);
364 uid = UUID.nameUUIDFromBytes(buffer.toString().getBytes()).toString();
365 }
366 } catch (MessagingException e) {
367 LOG.warn("Cannot reader headers from mail message. This exception will be ignored.", e);
368 }
369
370 return uid;
371 }
372
373 private void ensureIsConnected() throws MessagingException {
374 MailConfiguration config = getEndpoint().getConfiguration();
375
376 boolean connected = false;
377 try {
378 if (store != null && store.isConnected()) {
379 connected = true;
380 }
381 } catch (Exception e) {
382 LOG.debug("Exception while testing for is connected to MailStore: "
383 + getEndpoint().getConfiguration().getMailStoreLogInformation()
384 + ". Caused by: " + e.getMessage(), e);
385 }
386
387 if (!connected) {
388 // ensure resources get recreated on reconnection
389 store = null;
390 folder = null;
391
392 if (LOG.isDebugEnabled()) {
393 LOG.debug("Connecting to MailStore: " + getEndpoint().getConfiguration().getMailStoreLogInformation());
394 }
395 store = sender.getSession().getStore(config.getProtocol());
396 store.connect(config.getHost(), config.getPort(), config.getUsername(), config.getPassword());
397 }
398
399 if (folder == null) {
400 if (LOG.isDebugEnabled()) {
401 LOG.debug("Getting folder " + config.getFolderName());
402 }
403 folder = store.getFolder(config.getFolderName());
404 if (folder == null || !folder.exists()) {
405 throw new FolderNotFoundException(folder, "Folder not found or invalid: " + config.getFolderName());
406 }
407 }
408 }
409
410 @Override
411 public MailEndpoint getEndpoint() {
412 return (MailEndpoint) super.getEndpoint();
413 }
414
415 }