module Paperclip # Paperclip processors allow you to modify attached files when they are # attached in any way you are able. Paperclip itself uses command-line # programs for its included Thumbnail processor, but custom processors # are not required to follow suit. # # Processors are required to be defined inside the Paperclip module and # are also required to be a subclass of Paperclip::Processor. There is # only one method you *must* implement to properly be a subclass: # #make, but #initialize may also be of use. Both methods accept 3 # arguments: the file that will be operated on (which is an instance of # File), a hash of options that were defined in has_attached_file's # style hash, and the Paperclip::Attachment itself. # # All #make needs to return is an instance of File (Tempfile is # acceptable) which contains the results of the processing. # # See Paperclip.run for more information about using command-line # utilities from within Processors. class Processor attr_accessor :file, :options, :attachment def initialize file, options = {}, attachment = nil @file = file @options = options @attachment = attachment end def make end def self.make file, options = {}, attachment = nil new(file, options, attachment).make end end # Due to how ImageMagick handles its image format conversion and how Tempfile # handles its naming scheme, it is necessary to override how Tempfile makes # its names so as to allow for file extensions. Idea taken from the comments # on this blog post: # http://marsorange.com/archives/of-mogrify-ruby-tempfile-dynamic-class-definitions class Tempfile < ::Tempfile # This is Ruby 1.8.7's implementation. if RUBY_VERSION <= "1.8.6" || RUBY_PLATFORM =~ /java/ def make_tmpname(basename, n) case basename when Array prefix, suffix = *basename else prefix, suffix = basename, '' end t = Time.now.strftime("%y%m%d") path = "#{prefix}#{t}-#{$$}-#{rand(0x100000000).to_s(36)}-#{n}#{suffix}" end end end end