com.google.gerrit.server.mail.receive.ImapMailReceiver Maven / Gradle / Ivy
// Copyright (C) 2016 The Android Open Source Project
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package com.google.gerrit.server.mail.receive;
import com.google.common.flogger.FluentLogger;
import com.google.gerrit.mail.MailMessage;
import com.google.gerrit.mail.MailParsingException;
import com.google.gerrit.mail.RawMailParser;
import com.google.gerrit.server.git.WorkQueue;
import com.google.gerrit.server.mail.EmailSettings;
import com.google.gerrit.server.mail.Encryption;
import com.google.inject.Inject;
import com.google.inject.Singleton;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import org.apache.commons.net.imap.IMAPClient;
import org.apache.commons.net.imap.IMAPSClient;
@Singleton
public class ImapMailReceiver extends MailReceiver {
private static final FluentLogger logger = FluentLogger.forEnclosingClass();
private static final String INBOX_FOLDER = "INBOX";
@Inject
ImapMailReceiver(EmailSettings mailSettings, MailProcessor mailProcessor, WorkQueue workQueue) {
super(mailSettings, mailProcessor, workQueue);
}
/**
* Opens a connection to the mail server, removes emails where deletion is pending, reads new
* email and closes the connection.
*
* @param async determines if processing messages should happen asynchronously
* @throws MailTransferException in case of a known transport failure
* @throws IOException in case of a low-level transport failure
*/
@Override
public synchronized void handleEmails(boolean async) throws MailTransferException, IOException {
IMAPClient imap;
if (mailSettings.encryption != Encryption.NONE) {
imap = new IMAPSClient(mailSettings.encryption.name(), true);
} else {
imap = new IMAPClient();
}
if (mailSettings.port > 0) {
imap.setDefaultPort(mailSettings.port);
}
// Set a 30s timeout for each operation
imap.setDefaultTimeout(30 * 1000);
imap.connect(mailSettings.host);
try {
if (!imap.login(mailSettings.username, mailSettings.password)) {
throw new MailTransferException("Could not login to IMAP server");
}
try {
if (!imap.select(INBOX_FOLDER)) {
throw new MailTransferException("Could not select IMAP folder " + INBOX_FOLDER);
}
// Fetch just the internal dates first to know how many messages we
// should fetch.
if (!imap.fetch("1:*", "(INTERNALDATE)")) {
// false indicates that there are no messages to fetch
logger.atInfo().log("Fetched 0 messages via IMAP");
return;
}
// Format of reply is one line per email and one line to indicate
// that the fetch was successful.
// Example:
// * 1 FETCH (INTERNALDATE "Mon, 24 Oct 2016 16:53:22 +0200 (CEST)")
// * 2 FETCH (INTERNALDATE "Mon, 24 Oct 2016 16:53:22 +0200 (CEST)")
// AAAC OK FETCH completed.
int numMessages = imap.getReplyStrings().length - 1;
logger.atInfo().log("Fetched %d messages via IMAP", numMessages);
// Fetch the full version of all emails
List mailMessages = new ArrayList<>(numMessages);
for (int i = 1; i <= numMessages; i++) {
if (imap.fetch(i + ":" + i, "(BODY.PEEK[])")) {
// Obtain full reply
String[] rawMessage = imap.getReplyStrings();
if (rawMessage.length < 2) {
continue;
}
// First and last line are IMAP status codes. We have already
// checked, that the fetch returned true (OK), so we safely ignore
// those two lines.
StringBuilder b = new StringBuilder(2 * (rawMessage.length - 2));
for (int j = 1; j < rawMessage.length - 1; j++) {
if (j > 1) {
b.append("\n");
}
b.append(rawMessage[j]);
}
try {
MailMessage mailMessage = RawMailParser.parse(b.toString());
if (pendingDeletion.contains(mailMessage.id())) {
// Mark message as deleted
if (imap.store(i + ":" + i, "+FLAGS", "(\\Deleted)")) {
pendingDeletion.remove(mailMessage.id());
} else {
logger.atSevere().log(
"Could not mark mail message as deleted: %s", mailMessage.id());
}
} else {
mailMessages.add(mailMessage);
}
} catch (MailParsingException e) {
logger.atSevere().withCause(e).log("Exception while parsing email after IMAP fetch");
}
} else {
logger.atSevere().log("IMAP fetch failed. Will retry in next fetch cycle.");
}
}
// Permanently delete emails marked for deletion
if (!imap.expunge()) {
logger.atSevere().log("Could not expunge IMAP emails");
}
dispatchMailProcessor(mailMessages, async);
} finally {
imap.logout();
}
} finally {
imap.disconnect();
}
}
}