如何使用django-mailer实现定时发送邮件

Question

我正在制作一个Django应用程序，需要能够创建电子邮件，并在指定的时间发送这些邮件。我想我可以使用django-mailer来把邮件放入队列中，然后再发送出去。但是尽管他们的示例中提到这是一个功能，我还是找不到具体的做法。

我需要在django-mailer的消息模型中设置一个'when_to_send'字段，当定时任务运行send_mail函数时，它需要过滤掉那些'when_to_send'日期晚于当前时间的邮件...

def send_all():
    """
    Send all eligible messages in the queue.
    """

    lock = FileLock("send_mail")

    logging.debug("acquiring lock...")
    try:
        lock.acquire(LOCK_WAIT_TIMEOUT)
    except AlreadyLocked:
        logging.debug("lock already in place. quitting.")
        return
    except LockTimeout:
        logging.debug("waiting for the lock timed out. quitting.")
        return
    logging.debug("acquired.")

    start_time = time.time()

    dont_send = 0
    deferred = 0
    sent = 0

    try:
        for message in prioritize():
            if DontSendEntry.objects.has_address(message.to_address):
                logging.info("skipping email to %s as on don't send list " % message.to_address)
                MessageLog.objects.log(message, 2) # @@@ avoid using literal result code
                message.delete()
                dont_send += 1
            else:
                try:
                    logging.info("sending message '%s' to %s" % (message.subject.encode("utf-8"), message.to_address.encode("utf-8")))
                    core_send_mail(message.subject, message.message_body, message.from_address, [message.to_address])
                    MessageLog.objects.log(message, 1) # @@@ avoid using literal result code
                    message.delete()
                    sent += 1
                except (socket_error, smtplib.SMTPSenderRefused, smtplib.SMTPRecipientsRefused, smtplib.SMTPAuthenticationError), err:
                    message.defer()
                    logging.info("message deferred due to failure: %s" % err)
                    MessageLog.objects.log(message, 3, log_message=str(err)) # @@@ avoid using literal result code
                    deferred += 1
    finally:
        logging.debug("releasing lock...")
        lock.release()
        logging.debug("released.")

    logging.info("")
    logging.info("%s sent; %s deferred; %s don't send" % (sent, deferred, dont_send))
    logging.info("done in %.2f seconds" % (time.time() - start_time))

有没有人知道如何自定义这个功能，以便不发送那些消息中'when_to_send'字段晚于当前时间的邮件？

Answer 1

你需要为 django-mailer 实现一个定时任务（cron job）：

* * * * * (cd $PINAX; /usr/local/bin/python2.5 manage.py send_mail >> $PINAX/cron_mail.log 2>&1)

然后在 engine.py 的第96行：

   # Get rid of "while True:"
   while not Message.objects.all():
        # Get rid of logging.debug("sleeping for %s seconds before checking queue again" % EMPTY_QUEUE_SLEEP)
        # Get rid of sleep
        send_all()

Answer 2

你只需要在处理消息的循环中添加一个新的条件判断（你还需要在文件的顶部导入datetime模块）：

         for message in prioritize():
            if DontSendEntry.objects.has_address(message.to_address):
                logging.info("skipping email to %s as on don't send list " % message.to_address)
                MessageLog.objects.log(message, 2) # @@@ avoid using literal result code
                message.delete()
                dont_send += 1
            elif message.when_to_send > datetime.datetime.now():
                continue
            else:
                try:
                  ... the rest of your code ...