Remove the Downloads::File class. Move download methods to
Danbooru::Http instead. This means that:
* HTTParty has been replaced with http.rb for downloading files.
* Downloading is no longer tightly coupled to source strategies. Before
Downloads::File tried to automatically look up the source and download
the full size image instead if we gave it a sample url. Now we can
do plain downloads without source strategies altering the url.
* The Cloudflare Polish check has been changed from checking for a
Cloudflare IP to checking for the CF-Polished header. Looking up the
list of Cloudflare IPs was slow and flaky during testing.
* The SSRF protection code has been factored out so it can be used for
normal http requests, not just for downloads.
* The Webmock gem can be removed, since it was only used for stubbing
out certain HTTParty requests in the download tests. The Webmock gem
is buggy and caused certain tests to fail during CI.
* The retriable gem can be removed, since we no longer autoretry failed
downloads. We assume that if a download fails once then retrying
probably won't help.
ref: https://danbooru.donmai.us/forum_topics/16935.
Bug: sample images were being generated to be at most 850px width *and*
850px tall. They're supposed to be at most 850px wide with unlimited height.
* Move image thumbnail generation code to MediaFile::Image.
* Move video thumbnail generation code to MediaFile::Video.
* Move ugoira->webm conversion code to MediaFile::Ugoira.
This separates thumbnail generation from the upload process so that it's
possible to generate thumbnails outside of uploads.
* Add MediaFile abstraction. A MediaFile represents an image or video file.
* Move filetype detection and dimension parsing code from uploads to MediaFile.
* Fix corrupted image detection. We were shelling out to vips and trying
to grep for error messages, but the error message for jpeg files changed.
Now we load the file in ruby vips, which raises an error on failure.
* Don't attempt to redownload corrupted images. If a download completes
without any errors yet the downloaded file is corrupt, then something is
wrong at the source and redownloading is unlikely to help. Let the
upload fail and the user retry if necessary.
* Validate that all uploads are uncorrupted, including files uploaded
from a computer, not just files uploaded from a source.
Bug: Uploading bad pixiv id images failed because the pixiv strategy
raised a BadIDError exception when the upload service checked for the
ugoira frame data.
* Rename Upload#download_for_upload to #get_file_for_upload.
* Fix #get_file_for_upload to raise error if no file or source url was given.
* Fix javascript upload validation to disallow submitting form if file is
not present and the source is not an url.
