In MastoAPI media descriptions are updated via the
media update API not upon post creation or post update.
This functionality was originally added about 6 years ago in
ba93396649 which was part of
https://git.pleroma.social/pleroma/pleroma/-/merge_requests/626 and
https://git.pleroma.social/pleroma/pleroma-fe/-/merge_requests/450.
They introduced image descriptions to the front- and backend,
but predate adoption of Mastodon API.
For a while adding an `descriptions` array on post creation might have
continued to work as an undocumented Pleroma extension to Masto API, but
at latest when OpenAPI specs were added for those endpoints four years
ago in 7803a85d2c, these codepaths ceased
to be used. The API specs don’t list a `descriptions` parameter and
any unknown parameters are stripped out.
The attachments_from_ids function is only called from
ScheduledActivity and ActivityDraft.create with the latter
only being called by CommonAPI.{post,update} whihc in turn
are only called from ScheduledActivity again, MastoAPI controller
and without any attachment or description parameter WelcomeMessage.
Therefore no codepath can contain a descriptions parameter.
Documentation was already clear on this only stripping GPS tags.
But there are more potentially sensitive metadata tags (e.g. author
and possibly description) and the name alone suggests a broader effect.
Thus change the filter to strip all metadata except for colourspace info
and orientation (technically it strips everything and then readds
selected tags).
Explicitly stripping CommonIFD0 is needed since -all does not modify
IFD0 due to TIFF storing some actual image data there. CommonIFD0 then
strips a bunch of commonly used actual metadata tags from IFD0, to my
understanding leaving TIFF image data and custom metadata tags intact.
As of exiftool 12.57 both formats are supported, but EXIF data is
optional for JXL and if exiftool doesn’t find a preexisting metadata
chunk it will create one and treat it as a minor error resulting in
a non-zero exit code.
Setting -ignoreMinorErrors avoids failing on such uploads.
Due to JSON-LD compaction the full address of public scope
may also occur in shorter forms and the spec requires us to treat them
all equivalently. To save us the pain of repeatedly checking for all
variants internally, normalise inbound data to just one form.
See note at: https://www.w3.org/TR/activitypub/#public-addressing
This needs to happen very early, even before the other addressing fixes
else an earlier validator will reject the object. This in turn required
to move the list-tpye normalisation earlier as well, but since I was
unsure about putting empty lists into the data when no such field
existed before, I excluded this case and thus the later fixing had to be
kept as well.
Fixes: AkkomaGang/akkoma#670
literally nothing uses C2S AP, and it's another route into core
systems which requires analysis and maintenance. A second API
is just extra surface for potentially bad things so let's take
it out back and obliterate it
by default just prevent job floods with a 1-seconds
uniqueness check, but override in RemoteFetcherWorker
for 5 minute uniqueness check over all states
:infinity is an option we can go for maybe at some point,
but that would prevent any refetches so maybe not idk.
