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Remove Attachment

The remove_attachment plugin allows you to delete attachments through checkboxes on the web form.

plugin :remove_attachment

The plugin adds the #remove_<name> accessor to your model, which removes the attached file if it receives a truthy value:

photo.image #=> #<Shrine::UploadedFile> 
photo.remove_image = 'true'
photo.image #=> nil 

This allows you to add a checkbox form field for removing attachments:

form_for photo do |f|
  # ... 
  f.check_box :remove_image
end

If you're using the Shrine::Attacher directly, you can use the Attacher#remove accessor:

attacher.file #=> #<Shrine::UploadedFile> 
attacher.remove = '1'
attacher.file #=> nil