If a new file is uploaded, it will be matched with a previously uploaded
file so we don't have to store duplicates. SHA256 is random enough and
also unlikely enough to cause collisions.
If this merge throws exception on scripts/upgrade.php and you recently
tried a nightly (i.e. during 2015-02-19) then just go back a commit or two
and try again.
Or delete the duplicate entries. Find the entries like this:
SELECT COUNT(*), urlhash FROM file_redirection
GROUP BY urlhash
HAVING COUNT(*) > 1;
then for each urlhash (or come up with a smart SQL query) do:
DELETE FROM file_redirection WHERE urlhash='hashfrompreviousquery' LIMIT 1;
You'll have to remove duplicates more than once if you have >2 identical
urlhash entries. LIMIT -1 might do that for you. I'm not sure.
Default is now to take still thumbnails of animated GIFs and then
show them as originals in an AttachmentListItem. The still frames
are mostly used with front-ends like qvitter.
In some development code I noticed that when handling File objects without
filename values, there would be problems calling getPath and such.
The width and height value testing will be validated later anyway, and by
removing such a narrow test we can use events to generate thumbnails of
media formats supported by recently added plugins on demand.
We're now capable of doing image rotation for thumbnails based on
EXIF orientation data. Also, thumbnails are tracked by filenames and
thus we can delete them from storage when we feel like it.
The File object now stores width and height of files that can
supply this kind of information. Formats which we can not read
natively in PHP do not currently benefit from this. However an
event hook will be introduced later.
The CreateFileImageThumbnail event is renamed to:
CreateFileImageThumbnailSource to clarify that the hooks should not
generate their own thumbnails but only the source image. Also it now
accepts File objects, not MediaFile objects.
The thumbnail generation is documented in the source code. For
developers, call 'getThumbnail' on a File object and hope for the best.
Default thumbnail sizes have increased to be more appealing.
Avoiding collisions with date (shorter than before) and 4 character
random alphanumeric string. I bet someone could mass-upload files
and generate all combinations of aaaa-zzzz during the course of a
day, but then maybe that user should be disabled anyway :)
(filling the collision space will cause a never-ending loop).
