Contents

#
# File::      AbstractExternalProgramProcessor.rb
# Author::    wkm
# Copyright:: 2009
# License::   GPL
#
# TODO: this abstraction assumes only one filter will ever be run on a file,
# which is rather naive. Need to add support to process a file multiple times.
#


module SiteFuel
  module Processor

    require 'tempfile'
    require 'sitefuel/processors/AbstractProcessor'

    
    # Defines an abstract processor that offloads the work onto an external program.
    # These are typically processors for handling binary files (eg. images)
    #
    # These processors spend a bunch of time ensuring the external program exists
    # and of the appropriate version; each filter then will typically setup more
    # parameters to pass to the program.
    class AbstractExternalProgramProcessor < AbstractProcessor

      def initialize
        super
        @output_filename = nil
      end

      def self.processor_type
        'External'
      end

      # processes a file using a given configuration
      def self.process_file(filename, config = {})
        proc = self.new()
        proc.configure(config)
        proc.set_file(filename)
        proc.generate
      end

      # sets the file used by this processor
      def set_file(filename)
        self.resource_name = filename
        self.original_size = File.size(filename)

        return self
      end

      # gives the output filename for this processor; typically this will
      # be a temporary file.
      def output_filename
        if @output_filename == nil
          @output_filename = Tempfile.new(File.basename(resource_name)).path
        end

        @output_filename
      end

      # generates the new document using external programs
      def generate
        self.execute
        self.processed_size = File.size(output_filename)
        return self
      end
      
    end

  end
end

Version data entries

2 entries across 2 versions & 1 rubygems

Version	Path
sitefuel-0.0.0b	lib/sitefuel/processors/AbstractExternalProgramProcessor.rb
sitefuel-0.0.0a	lib/sitefuel/processors/AbstractExternalProgramProcessor.rb