discourse/lib/file_helper.rb
Sam 766e67ce57 FEATURE: introduce lossy color optimization on resized pngs
This feature ensures optimized images run via pngquant, this results extreme amounts of savings for resized images. Effectively the only impact is that the color palette on small resized images is reduced to 256.

To ensure safety we only apply this optimisation to images smaller than 500k.

This commit also makes a bunch of image specs less fragile.
2019-01-02 17:20:02 +11:00

117 lines
2.9 KiB
Ruby

require "final_destination"
require "mini_mime"
require "open-uri"
class FileHelper
def self.log(log_level, message)
Rails.logger.public_send(
log_level,
"#{RailsMultisite::ConnectionManagement.current_db}: #{message}"
)
end
def self.is_supported_image?(filename)
filename =~ supported_images_regexp
end
class FakeIO
attr_accessor :status
end
def self.download(url,
max_file_size:,
tmp_file_name:,
follow_redirect: false,
read_timeout: 5,
skip_rate_limit: false,
verbose: false,
retain_on_max_file_size_exceeded: false)
url = "https:" + url if url.start_with?("//")
raise Discourse::InvalidParameters.new(:url) unless url =~ /^https?:\/\//
tmp = nil
fd = FinalDestination.new(
url,
max_redirects: follow_redirect ? 5 : 1,
skip_rate_limit: skip_rate_limit,
verbose: verbose
)
fd.get do |response, chunk, uri|
if tmp.nil?
# error handling
if uri.blank?
if response.code.to_i >= 400
# attempt error API compatibility
io = FakeIO.new
io.status = [response.code, ""]
raise OpenURI::HTTPError.new("#{response.code} Error: #{response.body}", io)
else
log(:error, "FinalDestination did not work for: #{url}") if verbose
throw :done
end
end
if response.content_type.present?
ext = MiniMime.lookup_by_content_type(response.content_type)&.extension
ext = "jpg" if ext == "jpe"
tmp_file_ext = "." + ext if ext.present?
end
tmp_file_ext ||= File.extname(uri.path)
tmp = Tempfile.new([tmp_file_name, tmp_file_ext])
tmp.binmode
end
tmp.write(chunk)
if tmp.size > max_file_size
unless retain_on_max_file_size_exceeded
tmp.close
tmp = nil
end
throw :done
end
end
tmp&.rewind
tmp
end
def self.optimize_image!(filename, allow_pngquant: false)
pngquant_options = false
if allow_pngquant
pngquant_options = { allow_lossy: true }
end
ImageOptim.new(
# GLOBAL
timeout: 15,
skip_missing_workers: true,
# PNG
optipng: { level: 2, strip: SiteSetting.strip_image_metadata },
advpng: false,
pngcrush: false,
pngout: false,
pngquant: pngquant_options,
# JPG
jpegoptim: { strip: SiteSetting.strip_image_metadata ? "all" : "none" },
jpegtran: false,
jpegrecompress: false,
).optimize_image!(filename)
end
def self.supported_images
@@supported_images ||= Set.new %w{jpg jpeg png gif svg ico}
end
def self.supported_images_regexp
@@supported_images_regexp ||= /\.(#{supported_images.to_a.join("|")})$/i
end
end