When you edit a message to contain links, and URL previews are
enabled, previously we'd throw an exception, because the realm ID
wasn't included in the event.
Also adds a test so that we can have effective test coverage on this
codepath, though this history is actually that I found the bug through
writing this test :).
We do not use `get_link_embed_data` for messsages sent by
bots, as bots often repeat the same URL over and over again
and are generally either text-focused or have their own
mechanisms to provide preview content.
Fixes#2968.
This change adds support for displaying inline open graph previews for
links posted into Zulip.
It is designed to interact correctly with message editing.
This adds the new settings.INLINE_URL_EMBED_PREVIEW setting to control
whether this feature is enabled.
By default, this setting is currently disabled, so that we can burn it
in for a bit before it impacts users more broadly.
Eventually, we may want to make this manageable via a (set of?)
per-realm settings. E.g. I can imagine a realm wanting to be able to
enable/disable it for certain URLs.
Tim Abbott
Steve Howell
Igor Tokarev