Various pieces of our thumbor-based thumbnailing system were already
merged; this adds the remaining pieces required for it to work:
* a THUMBOR_URL Django setting that controls whether thumbor is
enabled on the Zulip server (and if so, where thumbor is hosted).
* Replaces the overly complicated prototype cryptography logic
* Adds a /thumbnail endpoint (supported both on web and mobile) for
accessing thumbnails in messages, designed to support hosting both
external URLs as well as uploaded files (and applying Zulip's
security model for access to thumbnails of uploaded files).
* Modifies bugdown to, when THUMBOR_URL is set, render images with the
`src` attribute pointing /thumbnail (to provide a small thumbnail
for the image), along with adding a "data-original" attribute that
can be used to access the "original/full" size version of the image.
There are a few things that don't work quite yet:
* The S3 backend support is incomplete and doesn't work yet.
* The error pages for unauthorized access are ugly.
* We might want to rename data-original and /thumbnail?size=original
to use some other name, like "full", that better reflects the fact
that we're potentially not serving the original image URL.
This migrates Zulip to use a dramatically better set of names and
aliases for our emoji set, defined in emoji_names.py (which is in turn
manually generated from our hand-curated CSV file).
This should significantly improve the experience of using Zulip's
emoji picker and emoji typeahead for finding what one is looking for.
Add 3 new Markdown emoji tests for newlines, emphasis, and links. The
goal of these tests is to ensure that Markdown operations concerning
emoji are preformed in proper order, with emoji being added correctly
based on other Markdown operations.
See suggestion here: https://git.io/flF5W.
This bug is caused by the conversion of newlines to `<br>` statements,
since `>` is not allowed as a character around an emoticon during
translation.
Also, add a new test case for preventing this bug from occurring in the
future.
Fix#9763.