Resize existing images when using attachment_fu

If you use the attachment_fu plugin and want to resize all your existing image files after changing any of your thumbnail formats, write a littler runner script like this:

    1 # resize_images.rb
    2 only_this = ARGV[0]
    3 classes = [
    4   'Photo',
    5 ]
    6 classes = only_this.blank? ? classes : [only_this]
    7 classes.each do |klass|
    8   puts "resizing all #{klass.to_s.tableize}"
    9   Kernel.const_get(klass).find(:all, :conditions => 'parent_id IS NULL').each do |image|
   10     puts "...#{image.public_filename}"
   11     temp_file = image.create_temp_file
   12     image.attachment_options[:thumbnails].each { |suffix, size|
   13       image.create_or_update_thumbnail(temp_file, suffix, *size)
   14     }
   15   end
   16 end
   17 

which you can call with

./script/runner ./script/resize_images.rb 

if you want to resize all images stores with attachment_fu. Or if you only want to resize your Photo model images:

./script/runner ./script/resize_images.rb Photo

How to call a common deploy task during the deployment?

For example, if you want to clean up your releases directory on every deployment (using Capistrano), simply add the following lines to your deployment script:

#deploy.rb
after 'deploy', "deploy:cleanup"

That's it :-)