If a media asset is corrupt, include the error message from libvips or
ffmpeg in the "Vips:Error" or "FFmpeg:Error" fields in the media
metadata table.
Corrupt files can't be uploaded nowadays, but they could be in the past,
so we have some old corrupted files that we can't generate thumbnails
for. This lets us mark these files in the metadata so they're findable
with the tag search `exif:Vips:Error`.
Known bug: Vips has a single global error buffer that is shared between
threads and that isn't cleared between operations. So we can't reliably
get the actual error message because it may pick up errors from other
threads, or from previous operations in the same thread.
This directory contains library code used through Danbooru. This includes things like defining API clients, dealing with
sources, parsing tag searches, storing and resizing images, and so on.
Many of the files here use the Service Object pattern. Instead of putting complex code in models or controllers, it goes
here, in plain old Ruby objects (POROs). This keeps models and controllers simpler, and keeps domain logic isolated and
independent from the database and the HTTP request cycle.