demarches-normaliennes/app/jobs/image_processor_job.rb
2024-11-06 15:03:50 +01:00

104 lines
3.3 KiB
Ruby

# frozen_string_literal: true
class ImageProcessorJob < ApplicationJob
queue_as :low # thumbnails and watermarks. Execution depends of virus scanner which is more urgent
class FileNotScannedYetError < StandardError
end
# If by the time the job runs the blob has been deleted, ignore the error
discard_on ActiveRecord::RecordNotFound
# If the file is deleted during the scan, ignore the error
discard_on ActiveStorage::FileNotFoundError
discard_on ActiveRecord::InvalidForeignKey
# If the file is not an image, not in format we can process or the image is corrupted, ignore the error
DISCARDABLE_ERRORS = [
'improper image header',
'width or height exceeds limit',
'attempt to perform an operation not allowed by the security policy',
'no decode delegate for this image format'
]
discard_on do |_, error|
DISCARDABLE_ERRORS.any? { error.message.match?(_1) }
end
# If the file is not analyzed or scanned for viruses yet, retry later
# (to avoid modifying the file while it is being scanned).
retry_on FileNotScannedYetError, wait: :exponentially_longer, attempts: 10
# Usually invalid image or ImageMagick decoder blocked for this format
retry_on MiniMagick::Invalid, attempts: 3
retry_on MiniMagick::Error, attempts: 3
rescue_from ActiveStorage::PreviewError do
retry_or_discard
end
def perform(blob)
return if blob.nil?
raise FileNotScannedYetError if blob.virus_scanner.pending?
return if ActiveStorage::Attachment.find_by(blob_id: blob.id)&.record_type == "ActiveStorage::VariantRecord"
auto_rotate(blob) if ["image/jpeg", "image/jpg"].include?(blob.content_type)
uninterlace(blob) if blob.content_type == "image/png"
create_representations(blob) if blob.representation_required?
add_watermark(blob) if blob.watermark_pending?
end
private
def auto_rotate(blob)
blob.open do |file|
Tempfile.create(["rotated", File.extname(file)]) do |output|
processed = AutoRotateService.new.process(file, output)
return if processed.blank?
blob.upload(processed) # also update checksum & byte_size accordingly
blob.save!
end
end
end
def uninterlace(blob)
blob.open do |file|
processed = UninterlaceService.new.process(file)
return if processed.blank?
blob.upload(processed)
blob.save!
end
end
def create_representations(blob)
blob.attachments.each do |attachment|
next unless attachment&.representable?
attachment.representation(resize_to_limit: [400, 400]).processed
if attachment.blob.content_type.in?(RARE_IMAGE_TYPES)
attachment.variant(resize_to_limit: [2000, 2000]).processed
end
if attachment.record.class == ActionText::RichText
attachment.variant(resize_to_limit: [1024, 768]).processed
end
end
end
def add_watermark(blob)
return if blob.watermark_done?
blob.open do |file|
Tempfile.create(["watermarked", File.extname(file)]) do |output|
processed = WatermarkService.new.process(file, output)
return if processed.blank?
blob.upload(processed) # also update checksum & byte_size accordingly
blob.watermarked_at = Time.current
blob.save!
end
end
end
def retry_or_discard
if executions < 3
retry_job wait: 5.minutes
end
end
end