larsklevan / attachment_fu_app_engine

AttachmentFuAppEngine
=====================

Extension for AttachmentFu (http://github.com/technoweenie/attachment_fu) which uses the Google App Engine for storage 
and image resizing.  Removes the need to install ImageMagick and allows you to add or change thumbnail sizes without 
migrating previous data.

The Google App Engine backend code is included so you can run it in your own App Engine instance.

Example
=======

class Photo < ActiveRecord::Base
  has_attachment :storage => :app_engine, :thumbnails => {:small_square => "45x45!"}
end

AttachmentFuAppEngine attempts to reproduce the resize format from ImageMagick.

* "100x100"  - scale the image to fit within a 100x100 box (the larger dimension will be 100, such as 100x75), 
preserving the aspect ratio.  Will scale up small images.
* "100x100!" - scale the image to be exactly 100x100 by scaling proportionately and cropping off the edges.  Will not 
distort the image but may hide part of it.
* "100x100>" - scale the image to be at most 100x100 - smaller images will not be enlarged.

Limitations
===========

* Google App Engine is in early release, so if you go past your daily storage/bandwidth/CPU limit you are out of luck.
* Google App Engine does not support HTTPS.
* I haven't had much luck uploading large files (larger than 2 MB or so) to Google App Engine.  This plugin is mainly 
intended for photos so hopefully that restriction won't be a major issue.

Copyright (c) 2008 Lars Klevan, released under the MIT license