CarrierWave Uploader Modules

gistfile1.md

Uploader::UniqFilename to generate unique file name.

# lib/uploader/uniq_filename.rb
module Uploader
  module UniqFilename
    extend ActiveSupport::Concern

    def filename
      return if original_filename.blank?
      if file.extension.present?
        "#{secure_token}.#{file.extension}"
      else
        secure_token
      end
    end

    protected
    
    def secure_token(length = 10)
      var = :"@#{mounted_as}_secure_token"
      model.instance_variable_get(var) or model.instance_variable_set(var, SecureRandom.hex(length/2))
    end
  end
end

Uploader::UrlWithHost overrides the default url method, which returns the file url with host (for CDN purpose for example). Just configure hosts in CONFIG const.

module Uploader
  module UrlWithHost
    class Host
      class << self
        def config
          CONFIG[:uploader] || {}
        end

        def list
          config['hosts'] || []
        end
      end
    end
    
    extend ActiveSupport::Concern
    
    included do
      alias_method :url_without_host, :url

      define_method :url_with_host do |options ={}|
        path = url_without_host(options)
        return path if path.blank?
        return path if path.start_with?('http')
        hosts = Host.list

        return path if hosts.length.zero?
        hosts[model.id.to_i % hosts.length] + path.to_s
      end
      alias_method :url, :url_with_host
    end
  end
end