How to use paperclip to handle multiple file types

Question

How possible is it to use one single paperclip field to handle for different file types. For example, I have a file model with with a paperclip method that says:

has_attached_file :file

This file can be a picture, audio, video, or document.

If it's a picture, how can I make it such that the has_attached_file :file would be able to handle pictures in this way:

has_attached_file :file, styles: {thumb: "72x72#"}

Then if it's other document types, it would work just as normal without the style so I don't have to create fields for different file types.

score 6 · Accepted Answer · edited May 23 '17 at 10:29

The way you'll handle conditional styling is to use a lambda to determine what type of content you're dealing with. We've done this before with an earlier version of Rails / Paperclip:

#app/models/attachment.rb
Class Attachment < ActiveRecord::Base
    has_attached_file :file,
    styles: lambda { |a| a.instance.is_image? ? {:small => "x200>", :medium => "x300>", :large => "x400>"} : {}}  

    validates_attachment_content_type :file, :content_type => [/\Aimage\/.*\Z/, /\Avideo\/.*\Z/]

    private

    def is_image?
        attachment.instance.attachment_content_type =~ %r(image)
    end
end

score 4 · Answer 2 · edited May 05 '14 at 13:56

Thanks to Rich Peck's Answer i was able to solve my problem with this solution.

first of all use lambda to handle conditions

  has_attached_file :file,
                    styles: lambda { |a| a.instance.check_file_type}

then i defined a custom method named check_file_type

in this method i did the validations and checking with ease based on this ruby best pratice article

def check_file_type
    if is_image_type?
      {:small => "x200>", :medium => "x300>", :large => "x400>"}
    elsif is_video_type?
      {
          :thumb => { :geometry => "100x100#", :format => 'jpg', :time => 10, :processors => [:ffmpeg] },
          :medium => {:geometry => "250x150#", :format => 'jpg', :time => 10, :processors => [:ffmpeg]}
      }
    else
      {}
    end
  end

and defined my is_image_type? and is_video_type? to handle for both videos and images.

  def is_image_type?
    file_content_type =~ %r(image)
  end

  def is_video_type?
    file_content_type =~ %r(video)
  end

then my attachment validation now looks like this

validates_attachment_content_type :file, :content_type => [/\Aimage\/.*\Z/, /\Avideo\/.*\Z/, /\Aaudio\/.*\Z/, /\Aapplication\/.*\Z/]

with this method, i can now use one paperclip method to handle multiple file types.

How to use paperclip to handle multiple file types

2 Answers2