ruby-on-rails - Rails Carrierwave Base64 图片上传

Question

使用 Carrierwave 将图像从客户端上传到 Rails 后端的最佳方式是什么。现在我们的 iOS 开发人员将文件作为 base64 发送，所以请求是这样的:

"image_data"=>"/9j/4AAQSkZJRgABAQAAAQABAAD/4QBYRXhpZgAATU0AKgAAAAgAAgESAAMAAAABAAEAAIdpAAQAAAABAAAAJgAAAAAAA6ABAAMAAAABAAEAAKACAAQAAAABAAAAHqADAAQAAAABAAAAHgAAAAD/2wBDAAEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQH/2wBDAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQH/wAARCAAeAB4DAREAAhEBAxEB/8QAHwAAAQUBAQE....

所以，我的问题实际上是两个问题。我应该告诉他以不同的文件格式发送吗？如果 base64 是发送这些文件的正确方式，那么我该如何在载波中处理它们？

Answer 1

我认为一种解决方案是将解码后的数据保存到文件中，然后将此文件分配给挂载的 uploader 。然后删除该文件。

另一个(内存中)解决方案可以是这个:

# define class that extends IO with methods that are required by carrierwave
class CarrierStringIO < StringIO
  def original_filename
    # the real name does not matter
    "photo.jpeg"
  end

  def content_type
    # this should reflect real content type, but for this example it's ok
    "image/jpeg"
  end
end

# some model with carrierwave uploader
class SomeModel
  # the uploader
  mount_uploader :photo, PhotoUploader

  # this method will be called during standard assignment in your controller
  # (like `update_attributes`)
  def image_data=(data)
    # decode data and create stream on them
    io = CarrierStringIO.new(Base64.decode64(data))

    # this will do the thing (photo is mounted carrierwave uploader)
    self.photo = io
  end

end