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app/uploaders/attachment_uploader.rb

@@ -1,49 +1,13 @@
 # encoding: utf-8
 
 class AttachmentUploader < CarrierWave::Uploader::Base
-
-  # Include RMagick or ImageScience support:
-  # include CarrierWave::RMagick
-  # include CarrierWave::MiniMagick
-  # include CarrierWave::ImageScience
-
-  # Choose what kind of storage to use for this uploader:
   storage :file
-  # storage :fog
 
-  # Override the directory where uploaded files will be stored.
-  # This is a sensible default for uploaders that are meant to be mounted:
   def store_dir
     "uploads/#{model.class.to_s.underscore}/#{mounted_as}/#{model.id}"
   end
 
-  # Provide a default URL as a default if there hasn't been a file uploaded:
-  # def default_url
-  #   "/images/fallback/" + [version_name, "default.png"].compact.join('_')
-  # end
-
-  # Process files as they are uploaded:
-  # process scale: [200, 300]
-  #
-  # def scale(width, height)
-  #   # do something
-  # end
-
-  # Create different versions of your uploaded files:
-  # version :thumb do
-  #   process scale: [50, 50]
-  # end
-
-  # Add a white list of extensions which are allowed to be uploaded.
-  # For images you might use something like this:
-  # def extension_white_list
-  #   %w(jpg jpeg gif png)
-  # end
-
-  # Override the filename of the uploaded files:
-  # Avoid using model.id or version_name here, see uploader/store.rb for details.
-  # def filename
-  #   "something.jpg" if original_filename
-  # end
-
+  def image?
+    %w(png jpg jpeg).include?(file.extension)
+  end
 end