lib/carrierwave/uploader/versions.rb
module CarrierWave
module Uploader
module Versions
extend ActiveSupport::Concern
include CarrierWave::Uploader::Callbacks
included do
class_attribute :versions, :version_names, :version_options, :instance_reader => false, :instance_writer => false
self.versions = {}
self.version_names = []
attr_accessor :parent_version
after :cache, :cache_versions!
after :store, :store_versions!
after :remove, :remove_versions!
after :retrieve_from_cache, :retrieve_versions_from_cache!
after :retrieve_from_store, :retrieve_versions_from_store!
prepend Module.new {
def initialize(*)
super
@versions = nil
end
}
end
module ClassMethods
##
# Adds a new version to this uploader
#
# === Parameters
#
# [name (#to_sym)] name of the version
# [options (Hash)] optional options hash
# [&block (Proc)] a block to eval on this version of the uploader
#
# === Examples
#
# class MyUploader < CarrierWave::Uploader::Base
#
# version :thumb do
# process :scale => [200, 200]
# end
#
# version :preview, :if => :image? do
# process :scale => [200, 200]
# end
#
# version :square, :unless => :invalid_image_type? do
# process :scale => [100, 100]
# end
#
# end
#
def version(name, options = {}, &block)
name = name.to_sym
build_version(name, options)
versions[name].class_eval(&block) if block
versions[name]
end
def recursively_apply_block_to_versions(&block)
versions.each do |name, version|
version.class_eval(&block)
version.recursively_apply_block_to_versions(&block)
end
end
private
def build_version(name, options)
class_name = "#{name.to_s.camelize}VersionUploader"
if !versions.has_key?(name)
uploader = Class.new(self)
const_set(class_name, uploader)
uploader.version_names += [name]
uploader.versions = {}
uploader.processors = []
uploader.version_options = options
uploader.class_eval <<-RUBY, __FILE__, __LINE__ + 1
# Define the enable_processing method for versions so they get the
# value from the parent class unless explicitly overwritten
def self.enable_processing(value=nil)
self.enable_processing = value if value
if defined?(@enable_processing) && !@enable_processing.nil?
@enable_processing
else
superclass.enable_processing
end
end
# Regardless of what is set in the parent uploader, do not enforce the
# move_to_cache config option on versions because it moves the original
# file to the version's target file.
#
# If you want to enforce this setting on versions, override this method
# in each version:
#
# version :thumb do
# def move_to_cache
# true
# end
# end
#
def move_to_cache
false
end
RUBY
class_eval <<-RUBY, __FILE__, __LINE__ + 1
def #{name}
versions[:#{name}]
end
RUBY
else
parent = versions[name]
uploader = Class.new(parent)
parent.const_set(class_name, uploader)
uploader.processors = []
uploader.version_options = uploader.version_options.merge(options)
end
# Add the current version hash to class attribute :versions
self.versions = versions.merge(name => uploader)
end
end # ClassMethods
##
# Returns a hash mapping the name of each version of the uploader to an instance of it
#
# === Returns
#
# [Hash{Symbol => CarrierWave::Uploader}] a list of uploader instances
#
def versions
return @versions if @versions
@versions = {}
self.class.versions.each do |name, version|
@versions[name] = version.new(model, mounted_as)
@versions[name].parent_version = self
end
@versions
end
##
# === Returns
#
# [String] the name of this version of the uploader
#
def version_name
self.class.version_names.join('_').to_sym unless self.class.version_names.blank?
end
##
#
# === Parameters
#
# [name (#to_sym)] name of the version
#
# === Returns
#
# [Boolean] True when the version exists according to its :if or :unless condition
#
def version_exists?(name)
name = name.to_sym
return false unless self.class.versions.has_key?(name)
if_condition = self.class.versions[name].version_options[:if]
unless_condition = self.class.versions[name].version_options[:unless]
if if_condition
if if_condition.respond_to?(:call)
if_condition.call(self, :version => name, :file => file)
else
send(if_condition, file)
end
elsif unless_condition
if unless_condition.respond_to?(:call)
!unless_condition.call(self, :version => name, :file => file)
else
!send(unless_condition, file)
end
else
true
end
end
##
# Copies the parent's cache_id when caching a version file.
# This behavior is not essential but it makes easier to understand
# that the cached files are generated by the single upload attempt.
#
def cache!(*args)
self.cache_id = parent_version.cache_id if parent_version
super
end
##
# When given a version name as a parameter, will return the url for that version
# This also works with nested versions.
# When given a query hash as a parameter, will return the url with signature that contains query params
# Query hash only works with AWS (S3 storage).
#
# === Example
#
# my_uploader.url # => /path/to/my/uploader.gif
# my_uploader.url(:thumb) # => /path/to/my/thumb_uploader.gif
# my_uploader.url(:thumb, :small) # => /path/to/my/thumb_small_uploader.gif
# my_uploader.url(:query => {"response-content-disposition" => "attachment"})
# my_uploader.url(:version, :sub_version, :query => {"response-content-disposition" => "attachment"})
#
# === Parameters
#
# [*args (Symbol)] any number of versions
# OR/AND
# [Hash] query params
#
# === Returns
#
# [String] the location where this file is accessible via a url
#
def url(*args)
if (version = args.first) && version.respond_to?(:to_sym)
raise ArgumentError, "Version #{version} doesn't exist!" if versions[version.to_sym].nil?
# recursively proxy to version
versions[version.to_sym].url(*args[1..-1])
elsif args.first
super(args.first)
else
super
end
end
##
# Recreate versions and reprocess them. This can be used to recreate
# versions if their parameters somehow have changed.
#
def recreate_versions!(*names)
# As well as specified versions, we need to reprocess versions
# that are the source of another version.
self.cache_id = CarrierWave.generate_cache_id
derived_versions.each do |name, v|
v.cache!(file) if names.empty? || !(v.descendant_version_names & names).empty?
end
active_versions.each do |name, v|
v.store! if names.empty? || names.include?(name)
end
end
protected
def descendant_version_names
[version_name] + derived_versions.flat_map do |name, version|
version.descendant_version_names
end
end
def active_versions
versions.select do |name, uploader|
version_exists?(name)
end
end
private
def derived_versions
active_versions.reject do |name, v|
v.class.version_options[:from_version]
end.to_a + active_sibling_versions.select do |name, v|
v.class.version_options[:from_version] == self.class.version_names.last
end.to_a
end
def active_sibling_versions
parent_version&.active_versions || []
end
def full_filename(for_file)
[version_name, super(for_file)].compact.join('_')
end
def full_original_filename
[version_name, super].compact.join('_')
end
def cache_versions!(new_file)
derived_versions.each { |name, v| v.cache!(new_file) }
end
def store_versions!(new_file)
active_versions.each { |name, v| v.store!(new_file) }
end
def remove_versions!
versions.each { |name, v| v.remove! }
end
def retrieve_versions_from_cache!(cache_name)
active_versions.each { |name, v| v.retrieve_from_cache!(cache_name) }
end
def retrieve_versions_from_store!(identifier)
active_versions.each { |name, v| v.retrieve_from_store!(identifier) }
end
end # Versions
end # Uploader
end # CarrierWave