如何将其他变量传递给 Rails 中的 CarrierWave 上传器？

Question

我看到这个问题多年来被问过几次（例如 Upload path based on a record value for Carrier wave Direct, Passing a parameter to the uploader / accessing a model's attribute from within the uploader / letting the user pick the thumbnail size），但我确信我一定是把它复杂化了，因为它看起来是一个非常简单的问题...

我有一个非常简单的 Video 模型可以安装上传器：

class Video < ApplicationRecord
  mount_uploader :file, VideoUploader
end

在控制器中，我允许两个参数：

    def video_params
      params.require(:video).permit(:title, :file)
    end

在实际的 VideoUploader 中，我似乎可以使用 class 内置函数（例如 original_filename）访问从 :file 列派生的许多变量，并且我可以使用 ffmpeg 参数处理文件。但是，我希望参数是基于 :title 字符串的条件，并且我没有知道如何限定它的范围或访问它。确保这些方法可以访问此变量的绝对最简单的方法是什么？

编辑：这是上传代码：

class VideoUploader < CarrierWave::Uploader::Base

  require 'streamio-ffmpeg'
  include CarrierWave::Video
  case @title # not working
  when "tblend_glitch"
    process encode_video: [:mp4,
      resolution: "1280x960",
      custom: %w(-to 5 -vf scale=-2:720,tblend=all_mode=difference,tblend=all_mode=difference,tblend=all_mode=difference,spp=4:10,tblend=all_mode=average,tblend=all_mode=difference,tblend=all_mode=difference,tblend=all_mode=difference,spp=4:10,tblend=all_mode=average,tblend=all_mode=difference,tblend=all_mode=difference,tblend=all_mode=difference,spp=4:10,tblend=all_mode=average,tblend=all_mode=difference,tblend=all_mode=difference,tblend=all_mode=difference)]
...
  end
  def full_filename(for_file)
    super.chomp(File.extname(super)) + '.mp4'
  end
  def filename
    original_filename.chomp(File.extname(original_filename)) + '.mp4'
  end
  storage :file
  def store_dir
    "uploads/#{model.class.to_s.underscore}/#{mounted_as}/#{model.id}"
  end
end

谢谢！

Answer 1

您应该能够使用 model 方法访问上传器中的实例。

您还没有定义 @title — 它是 nil。您可以使用以下代码创建条件版本。

class VideoUploader < CarrierWave::Uploader::Base
  version :tblend, if: :tblend_glitch? do # use a better version name
    process encode_video: [:mp4,
      resolution: "1280x960",
      custom: %w(-to 5 -vf scale=-2:720,tblend=all_mode=difference,tblend=all_mode=difference,tblend=all_mode=difference,spp=4:10,tblend=all_mode=average,tblend=all_mode=difference,tblend=all_mode=difference,tblend=all_mode=difference,spp=4:10,tblend=all_mode=average,tblend=all_mode=difference,tblend=all_mode=difference,tblend=all_mode=difference,spp=4:10,tblend=all_mode=average,tblend=all_mode=difference,tblend=all_mode=difference,tblend=all_mode=difference)]
  end

   # rest of the code

  private

  def tblend_glitch?
    model.title == 'tblend_glitch'
  end
end

参考：https://github.com/carrierwaveuploader/carrierwave#conditional-versions

如何将其他变量传递给 Rails 中的 CarrierWave 上传器？

How do you pass additional variables to a CarrierWave uploader in Rails?

ruby

ruby-on-rails

carrierwave