Use single attachment for video/image in paperclip

问题

I am using paperclip for uploading file ( video and images). Have used the same attachment(source) for both video and images.

class Media < ActiveRecord::Base
  belongs_to :memory
  validates_attachment_presence :source
  validates_attachment_content_type :source,
    :content_type => ['video/mp4', 'image/png', 'image/jpeg', 'image/jpg', 'image/gif']
end

Now I wanted to display different error messages in different cases.

1. When uploading file is image type but not the jpg/png/jpeg/gif.
2. When uploaded file is video type but not the mp4

How can i achieve this ? Any help would highly appreciated.

回答1:

So finally I got the solution. I added 2 conditional validation for the same

class Media < ActiveRecord::Base
  belongs_to :memory
  validates_attachment_presence :source
  validates_attachment_content_type :source,
    :content_type => ['video/mp4'],
    :message => "Sorry, right now we only support MP4 video",
    :if => :is_type_of_video?
  validates_attachment_content_type :source,
     :content_type => ['image/png', 'image/jpeg', 'image/jpg', 'image/gif'],
     :message => "Different error message",
     :if => :is_type_of_image?
  has_attached_file :source

  protected
  def is_type_of_video?
    source.content_type =~ %r(video)
  end

  def is_type_of_image?
    source.content_type =~ %r(image)
  end
end

来源：https://stackoverflow.com/questions/7149985/use-single-attachment-for-video-image-in-paperclip