Загрузка и копирование файлов, загруженных на S3 с помощью CarrierWave

Ответ 1

Мне удалось решить проблему с помощью @ffoeg

Решение, предлагаемое @ffoeg, не очень хорошо работает для меня, так как я имел дело с zip файлами > 500 МБ, что вызвало у меня проблемы с Heroku. Я переместил zipping в фоновый процесс, используя resque:

приложение/рабочие/photo_zipper.rb:

require 'zip/zip'
require 'zip/zipfilesystem'
require 'open-uri'
class PhotoZipper
  @queue = :photozip_queue

  #I pass 
  def self.perform(id_of_object_with_images, id_of_user_to_be_notified)
    user_mail = User.where(:id => id_of_user_to_be_notified).pluck(:email)
    export = PhotoZipper.generate_zip(id_of_object_with_images, id_of_user_to_be_notified)

    Notifications.zip_ready(export.archive_url, user_mail).deliver
  end

    # Zipfile generator
  def self.generate_zip(id_of_object_with_images, id_of_user_to_be_notified)
    object = ObjectWithImages.find(id_of_object_with_images)
    photos = object.images
    # base temp dir
    temp_dir = Dir.mktmpdir
    # path for zip we are about to create, I find that ruby zip needs to write to a real file
    # This assumes the ObjectWithImages object has an attribute title which is a string.
    zip_path = File.join(temp_dir, "#{object.title}_#{Date.today.to_s}.zip")

    Zip::ZipOutputStream.open(zip_path) do |zos|
      photos.each do |photo|
        path = photo.photo.path
        zos.put_next_entry(path)
        zos.write photo.photo.file.read
      end
    end

    #Find the user that made the request
    user = User.find(id_of_user_to_be_notified)

    #Create an export object associated to the user
    export = user.exports.build

    #Associate the created zip to the export
    export.archive = File.open(zip_path)

    #Upload the archive
    export.save!

    #return the export object
    export
  ensure

    # clean up the tempdir now!
    FileUtils.rm_rf temp_dir if temp_dir
  end


end

приложение/контроллеры/photos_controller.rb:

  format.zip do
    #pick the last ObjectWithImages.. ofcourse you should include your own logic here
    id_of_object_with_images = ObjectWithImages.last.id

    #enqueue the Photozipper task
    Resque.enqueue(PhotoZipper, id_of_object_with_images, current_user.id)

    #don't keep the user waiting and flash a message with information about what happening behind the scenes
    redirect_to some_path, :notice => "Your zip is being created, you will receive an e-mail once this process is complete"
  end

Большое спасибо @ffoeg за то, что помогли мне. Если ваши молнии меньше, вы можете попробовать решение @ffoeg.

Ответ 2

Вот мой прием. Там могут быть опечатки, но я думаю, что это суть этого:)

# action method, stream the zip
def download_photos_as_zip # silly name but you get the idea
  generate_zip do |zipname, zip_path|
    File.open(zip_path, 'rb') do |zf|
      # you may need to set these to get the file to stream (if you care about that)
      # self.last_modified
      # self.etag
      # self.response.headers['Content-Length']
      self.response.headers['Content-Type'] = "application/zip"
      self.response.headers['Content-Disposition'] = "attachment; filename=#{zipname}"
      self.response.body = Enumerator.new do |out| # Enumerator is ruby 1.9
        while !zf.eof? do
          out << zf.read(4096)
        end
      end
    end
  end
end


# Zipfile generator
def generate_zip(&block)
  photos = Photo.all
  # base temp dir
  temp_dir = Dir.mktempdir
  # path for zip we are about to create, I find that ruby zip needs to write to a real file
  zip_path = File.join(temp_dir, 'export.zip')
  Zip::ZipFile::open(zip_path, true) do |zipfile|
    photos.each do |photo|
      zipfile.get_output_stream(photo.photo.identifier) do |io|
        io.write photo.photo.file.read
      end
    end
  end
  # yield the zipfile to the action
  block.call 'export.zip', zip_path
ensure
  # clean up the tempdir now!
  FileUtils.rm_rf temp_dir if temp_dir
end