Hashing

Purpose

To secure your attachments by hiding the actual directory structure from prying eyes.

Configuration

Add an initializer:

# config/initializers/paperclip_defaults.rb

Paperclip::Attachment.default_options.update({
  :path => ":class/:attachment/:hash/:style.:extension",
  :hash_secret => ENV[RANDOM_SECRET],
  :hash_data => ":class/:attachment/:id/:style/:updated_at"
})

The :hash interpolation is generated from :hash_secret and the pattern given by the :hash_data option, which by default is ":class/:attachment/:id/:style/:updated_at", as shown.

Generate the :hash_secret using SecureRandom.base64(128) from a rails console to generate a relatively secure random string.

Once you've got that set up, defining attachments requires no modifications to get the new hashing behavior:

class Profile
  has_attached_file :portrait
end