There seems to have been a confusion between two different uses of the
word “optional”:
• An optional parameter may be omitted and replaced with a default
value.
• An Optional type has None as a possible value.
Sometimes an optional parameter has a default value of None, or None
is otherwise a meaningful value to provide, in which case it makes
sense for the optional parameter to have an Optional type. But in
other cases, optional parameters should not have Optional type. Fix
them.
Signed-off-by: Anders Kaseorg <anders@zulip.com>
Fixes#2665.
Regenerated by tabbott with `lint --fix` after a rebase and change in
parameters.
Note from tabbott: In a few cases, this converts technical debt in the
form of unsorted imports into different technical debt in the form of
our largest files having very long, ugly import sequences at the
start. I expect this change will increase pressure for us to split
those files, which isn't a bad thing.
Signed-off-by: Anders Kaseorg <anders@zulip.com>
Our open graph parser logic sloppily mixed data obtained by parsing
open graph properties with trusted data set by our oembed parser.
We fix this by consistenly using our explicit whitelist of generic
properties (image, title, and description) in both places where we
interact with open graph properties. The fixes are redundant with
each other, but doing both helps in making the intent of the code
clearer.
This issue fixed here was originally reported as an XSS vulnerability
in the upcoming Inline URL Previews feature found by Graham Bleaney
and Ibrahim Mohamed using Pysa. The recent Oembed changes close that
vulnerability, but this change is still worth doing to make the
implementation do what it looks like it does.
Anders Kaseorg
Mateusz Mandera
Tim Abbott
Anders Kaseorg