document_uploadr.rb

# encoding: utf-8

class DocumentUploader < CarrierWave::Uploader::Base
  include ::CarrierWave::Backgrounder::Delay
  include CarrierWave::MimeTypes

  # Include RMagick or MiniMagick support:
  include CarrierWave::RMagick
  # include CarrierWave::MiniMagick
  include CarrierWave::UNOConv

  # Include the Sprockets helpers for Rails 3.1+ asset pipeline compatibility:
  include Sprockets::Helpers::RailsHelper
  include Sprockets::Helpers::IsolatedHelper
  
  configure do |config|
    config.remove_previously_stored_files_after_update = false
  end

  # Choose what kind of storage to use for this uploader:
  # storage :file
  storage :fog

  # Override the directory where uploaded files will be stored.
  # This is a sensible default for uploaders that are meant to be mounted:
  def store_dir
    ""
  end

  def cache_dir
    # when we go distributed, this needs to be shared between servers.
    '../tmp/uploads/'
  end
  
  # Provide a default URL as a default if there hasn't been a file uploaded:
  def default_url
  #   # For Rails 3.1+ asset pipeline compatibility:
    asset_path("icons/" + [version_name, "processing.gif"].compact.join('_'))
  #
  #   "/images/fallback/" + [version_name, "default.png"].compact.join('_')
  end

  # Process files as they are uploaded:
  # process scale: [200, 300]
  #
  # def scale(width, height)
  #   # do something
  # end

  process :set_content_type
  process :exif_rotate, if: :image?
  
  # Create different versions of your uploaded files:
  version :thumb512, if: :image? do
    process resize_to_fit: [512, 512]
  end
  
  version :pdf, if: :pdf_ready? do
    process uno_convert: 'pdf'

    # you can define methods right on the versions and they are available in the uploader instance for that version.
    def fog_attributes
      { "Content-Disposition" => "attachment; filename=\"#{model.original_filename}\"" }.merge super
    end
  end
  
  version :png512, from_version: :thumb512, if: :image? do
    process convert: 'png'
  end

  version :thumb64, from_version: :thumb512, if: :image? do
    process resize_to_fit: [64, 64]
  end

  # Add a white list of extensions which are allowed to be uploaded.
  # For images you might use something like this:
  # def extension_white_list
  #   %w(jpg jpeg gif png)
  # end

  # Override the filename of the uploaded files:
  # Avoid using model.id or version_name here, see uploader/store.rb for details.
  def filename
    if original_filename
      if (name = model.try(:read_attribute, :file)).present?
        name
      else
        @name ||= "#{secure_token}.#{file.extension}" if original_filename.present?
      end
    end
  end

  def fog_attributes
    { "Content-Disposition" => "inline; filename=\"#{model.original_filename}\"" }.merge super
  end
  
  def secure_token
    model.secure_token ||= SecureRandom.uuid
  end

  protected
  def image? new_file
    model.image?
  end
  
  def pdf_ready? new_file
    model.pdf_ready?
  end

  # Rotates the image based on the EXIF Orientation
  def exif_rotate
    manipulate! { |img| img.auto_orient }
  end

end