Paperclip Duplicate Checker

**Author** Tim Morgan
**Version** 1.0 (Apr 20, 2012)
**License** Released under the MIT license.

This class extends Paperclip, adding a feature that forgoes uploading a replacement for an existing attachment file if the replacement is identical to the existing file.

In order for this to work, your model _must_have an <attachment>_fingerprint column, since MD5 fingerprints are used for comparison. To use, simply follow this example:

ruby class MyModel < ActiveRecord::Base include CheckForDuplicateAttachedFile has_attachment :note check_for_duplicate_attached_file :note end

Et voila! You save on bandwidth costs if your code re-uploads a lot of the same files.