* mail queue processor

1 files changed, 78 insertions, 0 deletions

diff --git a/app/backend/mail_queue.py b/app/backend/mail_queue.py
new file mode 100644
index 0000000..5ab600a
--- /dev/null
+++ b/app/backend/mail_queue.py
@@ -0,0 +1,78 @@
+import datetime
+import json
+import os
+
+import emails
+from dateutil.tz import tzutc
+from rcal.db import Session
+from rcal.model import MailQueue
+
+BASEPATH = os.path.join(
+    os.environ['PYTHONPATH'],
+    '..',
+    '..')
+
+
+def get_config(section, filename='config/mailer.json'):
+    config = json.load(open(os.path.join(BASEPATH, filename)))
+    return config[section]
+
+
+def get_queue(session, queue_config):
+    return session.query(MailQueue).filter(
+        MailQueue.is_sent.is_(False),
+        MailQueue.send_attempts <= queue_config['retry']
+    ).order_by(
+        MailQueue.send_attempts.desc(),
+        MailQueue.last_attempt_time
+    ).limit(queue_config['batch']).all()
+
+
+def prepare_message(item, sender):
+    msg = emails.Message(html=item.html_body,
+                         text=item.text_body.strip(),
+                         subject=item.subject.strip(),
+                         mail_from=(sender['name'], sender['from']))
+    if sender['send_copies']:
+        msg.set_bcc((sender['name'], sender['from']))
+    return msg
+
+
+def dump_error(item, retry_limit):
+    print ('Message #%d to %s reached maximum failed send attepmts (%d), dropping from queue.'
+           'Message created: %s'
+           'Last error message: %s') % (
+               item.id, item.recipient_mail, retry_limit,
+               item.create_time,
+               item.last_error_info)
+
+
+def main():
+    session = Session.create()
+
+    queue_config = get_config('queue')
+    sender = get_config('mail')
+    smtp_conf = get_config('smtp')
+
+    for item in get_queue(session, queue_config):
+        item.send_attempts += 1
+        item.last_attempt_time = datetime.datetime.now(tzutc())
+
+        msg = prepare_message(item, sender)
+        msg_response = msg.send(to=(item.recipient_name, item.recipient_mail),
+                                smtp={'host': smtp_conf['host'],
+                                      'port': smtp_conf['port'],
+                                      'ssl': smtp_conf['tls'],
+                                      'user': smtp_conf['user'],
+                                      'password': smtp_conf['pass']})
+        if msg_response.status_code in [250, ]:
+            item.is_sent = True
+        else:
+            item.last_error_info = msg_response.status_text
+            if item.send_attempts >= queue_config['retry']:
+                dump_error(item, queue_config['retry'])
+
+    session.commit()
+
+if __name__ == '__main__':
+    main()