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content in inbox by email clients like gmail. Since the leading
images were used mostly for decoration this made the preview
content gibberish. It's fine to set the alt attributes to empty
from accessibility point of view since the old alt attributes
did't added any meaningful information.
responses is an module analogous to httpretty for mocking external
URLs, with a very similar interface (potentially cleaner in that it
makes use of context managers).
The most important (in the moment) problem with httpretty is that it
breaks the ability to use redis in parts of code where httpretty is
enabled. From more research, the module in general has tendency to
have various troublesome bugs with breaking URLs that it shouldn't be
affecting, caused by it working at the socket interface layer. While
those issues could be fixed, responses seems to be less buggy (based
on both third-party reports like ckan/ckan#4755 and our own experience
in removing workarounds for bugs in httpretty) and is more actively
maintained.
Zulip has had a small use of WebSockets (specifically, for the code
path of sending messages, via the webapp only) since ~2013. We
originally added this use of WebSockets in the hope that the latency
benefits of doing so would allow us to avoid implementing a markdown
local echo; they were not. Further, HTTP/2 may have eliminated the
latency difference we hoped to exploit by using WebSockets in any
case.
While we’d originally imagined using WebSockets for other endpoints,
there was never a good justification for moving more components to the
WebSockets system.
This WebSockets code path had a lot of downsides/complexity,
including:
* The messy hack involving constructing an emulated request object to
hook into doing Django requests.
* The `message_senders` queue processor system, which increases RAM
needs and must be provisioned independently from the rest of the
server).
* A duplicate check_send_receive_time Nagios test specific to
WebSockets.
* The requirement for users to have their firewalls/NATs allow
WebSocket connections, and a setting to disable them for networks
where WebSockets don’t work.
* Dependencies on the SockJS family of libraries, which has at times
been poorly maintained, and periodically throws random JavaScript
exceptions in our production environments without a deep enough
traceback to effectively investigate.
* A total of about 1600 lines of our code related to the feature.
* Increased load on the Tornado system, especially around a Zulip
server restart, and especially for large installations like
zulipchat.com, resulting in extra delay before messages can be sent
again.
As detailed in
https://github.com/zulip/zulip/pull/12862#issuecomment-536152397, it
appears that removing WebSockets moderately increases the time it
takes for the `send_message` API query to return from the server, but
does not significantly change the time between when a message is sent
and when it is received by clients. We don’t understand the reason
for that change (suggesting the possibility of a measurement error),
and even if it is a real change, we consider that potential small
latency regression to be acceptable.
If we later want WebSockets, we’ll likely want to just use Django
Channels.
Signed-off-by: Anders Kaseorg <anders@zulipchat.com>
Since we don’t support downgrading from master to any 2.0.x release,
we shouldn’t set a ZULIP_VERSION that might lead someone to mistake
any such downgrade for an upgrade. ZULIP_VERSION should always be at
least a minor version ahead of LATEST_RELEASE_VERSION, except on the
release branch.
`.dev` is a decreasing suffix that sorts before `alpha`, `beta`, `rc`
according to PEP 440/`packaging.version.Version`.
Signed-off-by: Anders Kaseorg <anders@zulipchat.com>
For a long time, we've been only doing the zxcvbn password strength
checks on the browser, which is helpful, but means users could through
hackery (or a bug in the frontend validation code) manage to set a
too-weak password. We fix this by running our password strength
validation on the backend as well, using python-zxcvbn.
In theory, a bug in python-zxcvbn could result in it producing a
different opinion than the frontend version; if so, it'd be a pretty
bad bug in the library, and hopefully we'd hear about it from users,
report upstream, and get it fixed that way. Alternatively, we can
switch to shelling out to node like we do for KaTeX.
Fixes#6880.
`source-map` provides its own types, so with TypeScript configured
with `--moduleResolution node`, we don’t need the obsolete
`@types/source-map` package.
Signed-off-by: Anders Kaseorg <anders@zulipchat.com>
Send the `csrftoken` and `sessionid` cookies with `SameSite=Lax`.
This adds a layer of defense against CSRF attacks and matches the new
default in Django 2.1:
https://docs.djangoproject.com/en/2.1/releases/2.1/#samesite-cookies
This can be reverted when we upgrade to Django ≥ 2.1.
Signed-off-by: Anders Kaseorg <anders@zulipchat.com>
It happens that commonmark, python-jose, and python-twitter don’t
actually use future on Python 3, and moto uses aws-xray-sdk in such a
way that it doesn’t use future, but this was a weird game to be
playing just to remove one dependency, and it caused CI failures after
new releases of future, so let’s just include it.
Signed-off-by: Anders Kaseorg <anders@zulipchat.com>
The reason that `pip-tools` running on Python 3 didn’t detect the
right requirements for `thumbor` on Python 2 is simply that some of
them are conditional on the Python version.
As for the requirements that had been manually added as a workaround:
`backports-abc` and `singledispatch` are now correctly detected, while
`backports.ssl-match-hostname` was vendored into `urllib3` some time
ago and `certifi` is no longer necessary.
Signed-off-by: Anders Kaseorg <anders@zulipchat.com>
Also move it to dev.in.
Other notes for posterity: this should have been installed with a
pinned commit hash, and could have been installed directly from the
upstream Git repository, even on Python 3.7, as long as Cython was
installed as well.
Signed-off-by: Anders Kaseorg <anders@zulipchat.com>
Otherwise Bootstrap doesn’t get minified, and also the minification
state is incorrectly reflected in the webpack cache.
The Terser plugin is used by default; we need to include it explicitly
to avoid removing it.
Switch from cssnano to clean-css because it’s noticeably faster.
Signed-off-by: Anders Kaseorg <anders@zulipchat.com>