Question

以下是一个例子：

应用程序/模型/ book.rb

class Advertisement < ActiveRecord::Base

  enum kind: { magazine: 0, newspaper: 1 }
  mount_uploader :main_pic, BookMainPicUploader

  # ...

end

应用程序/上传/ book_main_pic_uploader.rb

class BookMainPicUploader < CarrierWave::Uploader::Base
  include CarrierWave::MiniMagick

  storage :fog

  def store_dir
    "uploads/featured/#{mounted_as}/#{model.id}"
  end

  def extension_white_list
    %w(jpg jpeg gif png)
  end

  version :normal do
    process resize_to_fill: [800, 400]
  end

  version :square do
    process resize_to_fill: [400, 400]
  end

end

上述代码会为每种类型的书籍创建正常版本和方形版本，但我们只想生成杂志的正常版本和仅报纸的正方形版本。

有可能实现吗？

Answer 1

您需要将version条件选项传递给if方法。

class BookMainPicUploader < CarrierWave::Uploader::Base
  include CarrierWave::MiniMagick

  storage :fog

  def store_dir
    "uploads/featured/#{mounted_as}/#{model.id}"
  end

  def extension_white_list
    %w(jpg jpeg gif png)
  end

  version :normal, if: :is_magazine? do
    process resize_to_fill: [800, 400]
  end

  version :square, if: :is_newspaper? do
    process resize_to_fill: [400, 400]
  end

  private

  def is_magazine? picture
    model.magazine?
  end

  def is_newspaper? picture
    model.newspaper?
  end

end

使用基于列值的carrierwave创建不同的映像版本

1 个答案: