This causes `upgrade-zulip-from-git`, as well as a no-option run of
`tools/build-release-tarball`, to produce a Zulip install running
Python 3, rather than Python 2. In particular this means that the
virtualenv we create, in which all application code runs, is Python 3.
One shebang line, on `zulip-ec2-configure-interfaces`, explicitly
keeps Python 2, and at least one external ops script, `wal-e`, also
still runs on Python 2. See discussion on the respective previous
commits that made those explicit. There may also be some other
third-party scripts we use, outside of this source tree and running
outside our virtualenv, that still run on Python 2.
This makes supervisor see the service as cheerfully running
and let it alone, rather than constantly retry starting it.
Because the crash/restart loop means repeatedly spending a
couple of seconds loading Django and the app, separated by
brief periods while supervisor notices the crash and acts
on it, it was actually consuming about 30-50% CPU on the
zulipchat.com staging server.
ScheduledJob was written for much more generality than it ended up being
used for. Currently it is used by send_future_email, and nothing
else. Tailoring the model to emails in particular will make it easier to do
things like selectively clear emails when people unsubscribe from particular
email types, or seamlessly handle using the same email on multiple realms.
This commit is a step towards the goal of replacing most of the
send_future_email pathway with a call to send_email.
Note that this commit changes the default value of sender from "Zulip
<NOREPLY_EMAIL_ADDRESS>" to "NOREPLY_EMAIL_ADDRESS". NOREPLY_EMAIL_ADDRESS
will soon be changed to have the Zulip in front.
datetime.utcnow() is a timezone-naive datetime. The Django ORM interprets it
in the settings.TIME_ZONE timezone (e.g. 'America/New_York' in the
development server). We perhaps haven't noticed errors yet since with
'America/New_York' all it means is that emails are sent 5 hours early, or a
slightly different set of messages are included in the digest.
This command should be run continuously via supervisor. It periodically
checks for new email messages to send, and then sends them. This is for
sending email that you've queued via the Email table, instead of mandrill
(as is the case for our localserver/development deploys).
(imported from commit a2295e97b70a54ba99d145d79333ec76b050b291)