Generate thumbnails on demand about gallery

[oparoz]

Closing as this needs to be dealt with in core so that we don't duplicate the effort.
Also, it won't work when encryption is enabled.

[oparoz]

From @deMattin on September 9, 2015 18:27

:sad:

[oparoz]

I know...but it shouldn't take more than 6 months since the basic mechanism is in place in core. It's just that previews is not a priority.

It can also be a separate app which just creates a cron which goes through the whole instance, looking for missing thumbnails.

I'm sure you could even create it. It would make 2 calls: isCached() and createPreview();

[oparoz]

Solution is available as an occ command: owncloud/gallery#387

Only available to admins, because this wouldn't work as a user callable command since it would probably time-out before the task could be completed.

[oparoz]