discourse/app/jobs/regular/pull_hotlinked_images.rb

220 lines
7.1 KiB
Ruby

# frozen_string_literal: true
module Jobs
class PullHotlinkedImages < ::Jobs::Base
sidekiq_options queue: 'low'
def initialize
@max_size = SiteSetting.max_image_size_kb.kilobytes
end
def execute(args)
disable_if_low_on_disk_space
@post_id = args[:post_id]
raise Discourse::InvalidParameters.new(:post_id) if @post_id.blank?
post = Post.find_by(id: @post_id)
return if post.nil? || post.topic.nil?
hotlinked_map = post.post_hotlinked_media.map { |r| [r.url, r] }.to_h
changed_hotlink_records = false
extract_images_from(post.cooked).each do |node|
download_src = original_src = node['src'] || node[PrettyText::BLOCKED_HOTLINKED_SRC_ATTR] || node['href']
download_src = "#{SiteSetting.force_https ? "https" : "http"}:#{original_src}" if original_src.start_with?("//")
normalized_src = normalize_src(download_src)
next if !should_download_image?(download_src, post)
hotlink_record = hotlinked_map[normalized_src]
if hotlink_record.nil?
hotlinked_map[normalized_src] = hotlink_record = PostHotlinkedMedia.new(
post: post,
url: normalized_src
)
begin
hotlink_record.upload = attempt_download(download_src, post.user_id)
hotlink_record.status = :downloaded
rescue ImageTooLargeError
hotlink_record.status = :too_large
rescue ImageBrokenError
hotlink_record.status = :download_failed
rescue UploadCreateError
hotlink_record.status = :upload_create_failed
end
end
if hotlink_record.changed?
changed_hotlink_records = true
hotlink_record.save!
end
rescue => e
raise e if Rails.env.test?
log(:error, "Failed to pull hotlinked image (#{download_src}) post: #{@post_id}\n" + e.message + "\n" + e.backtrace.join("\n"))
end
if changed_hotlink_records
post.trigger_post_process(
bypass_bump: true,
skip_pull_hotlinked_images: true # Avoid an infinite loop of job scheduling
)
end
if hotlinked_map.size > 0
Jobs.cancel_scheduled_job(:update_hotlinked_raw, post_id: post.id)
update_raw_delay = SiteSetting.editing_grace_period + 1
Jobs.enqueue_in(update_raw_delay, :update_hotlinked_raw, post_id: post.id)
end
end
def download(src)
downloaded = nil
begin
retries ||= 3
if SiteSetting.verbose_upload_logging
Rails.logger.warn("Verbose Upload Logging: Downloading hotlinked image from #{src}")
end
downloaded = FileHelper.download(
src,
max_file_size: @max_size,
retain_on_max_file_size_exceeded: true,
tmp_file_name: "discourse-hotlinked",
follow_redirect: true
)
rescue => e
if SiteSetting.verbose_upload_logging
Rails.logger.warn("Verbose Upload Logging: Error '#{e.message}' while downloading #{src}")
end
if (retries -= 1) > 0 && !Rails.env.test?
sleep 1
retry
end
end
downloaded
end
class ImageTooLargeError < StandardError; end
class ImageBrokenError < StandardError; end
class UploadCreateError < StandardError; end
def attempt_download(src, user_id)
# secure-media-uploads endpoint prevents anonymous downloads, so we
# need the presigned S3 URL here
src = Upload.signed_url_from_secure_media_url(src) if Upload.secure_media_url?(src)
hotlinked = download(src)
raise ImageBrokenError if !hotlinked
raise ImageTooLargeError if File.size(hotlinked.path) > @max_size
filename = File.basename(URI.parse(src).path)
filename << File.extname(hotlinked.path) unless filename["."]
upload = UploadCreator.new(hotlinked, filename, origin: src).create_for(user_id)
if upload.persisted?
upload
else
log(:info, "Failed to persist downloaded hotlinked image for post: #{@post_id}: #{src} - #{upload.errors.full_messages.join("\n")}")
raise UploadCreateError
end
end
def extract_images_from(html)
doc = Nokogiri::HTML5::fragment(html)
doc.css("img[src], [#{PrettyText::BLOCKED_HOTLINKED_SRC_ATTR}], a.lightbox[href]") -
doc.css("img.avatar") -
doc.css(".lightbox img[src]")
end
def should_download_image?(src, post = nil)
# make sure we actually have a url
return false unless src.present?
local_bases = [
Discourse.base_url,
Discourse.asset_host,
SiteSetting.external_emoji_url.presence
].compact.map { |s| normalize_src(s) }
if Discourse.store.has_been_uploaded?(src) || normalize_src(src).start_with?(*local_bases) || src =~ /\A\/[^\/]/i
return false if !(src =~ /\/uploads\// || Upload.secure_media_url?(src))
# Someone could hotlink a file from a different site on the same CDN,
# so check whether we have it in this database
#
# if the upload already exists and is attached to a different post,
# or the original_sha1 is missing meaning it was created before secure
# media was enabled, then we definitely want to redownload again otherwise
# we end up reusing existing uploads which may be linked to many posts
# already.
upload = Upload.consider_for_reuse(Upload.get_from_url(src), post)
return !upload.present?
end
# Don't download non-local images unless site setting enabled
return false unless SiteSetting.download_remote_images_to_local?
# parse the src
begin
uri = URI.parse(src)
rescue URI::Error
return false
end
hostname = uri.hostname
return false unless hostname
# check the domains blocklist
SiteSetting.should_download_images?(src)
end
def log(log_level, message)
Rails.logger.public_send(
log_level,
"#{RailsMultisite::ConnectionManagement.current_db}: #{message}"
)
end
protected
def normalize_src(src)
PostHotlinkedMedia.normalize_src(src)
end
def disable_if_low_on_disk_space
return if Discourse.store.external?
return if !SiteSetting.download_remote_images_to_local
return if available_disk_space >= SiteSetting.download_remote_images_threshold
SiteSetting.download_remote_images_to_local = false
# log the site setting change
reason = I18n.t("disable_remote_images_download_reason")
staff_action_logger = StaffActionLogger.new(Discourse.system_user)
staff_action_logger.log_site_setting_change("download_remote_images_to_local", true, false, details: reason)
# also send a private message to the site contact user notify_about_low_disk_space
notify_about_low_disk_space
end
def notify_about_low_disk_space
SystemMessage.create_from_system_user(Discourse.site_contact_user, :download_remote_images_disabled)
end
def available_disk_space
100 - DiskSpace.percent_free("#{Rails.root}/public/uploads")
end
end
end