diff options
Diffstat (limited to 'activesupport/lib')
7 files changed, 910 insertions, 321 deletions
diff --git a/activesupport/lib/active_support/cache.rb b/activesupport/lib/active_support/cache.rb index 7213b24f2d..ec5007c284 100644 --- a/activesupport/lib/active_support/cache.rb +++ b/activesupport/lib/active_support/cache.rb @@ -1,8 +1,12 @@ require 'benchmark' +require 'zlib' +require 'active_support/core_ext/array/extract_options' require 'active_support/core_ext/array/wrap' require 'active_support/core_ext/benchmark' require 'active_support/core_ext/exception' require 'active_support/core_ext/class/attribute_accessors' +require 'active_support/core_ext/numeric/bytes' +require 'active_support/core_ext/numeric/time' require 'active_support/core_ext/object/to_param' require 'active_support/core_ext/string/inflections' @@ -11,10 +15,16 @@ module ActiveSupport module Cache autoload :FileStore, 'active_support/cache/file_store' autoload :MemoryStore, 'active_support/cache/memory_store' - autoload :SynchronizedMemoryStore, 'active_support/cache/synchronized_memory_store' autoload :MemCacheStore, 'active_support/cache/mem_cache_store' + autoload :SynchronizedMemoryStore, 'active_support/cache/synchronized_memory_store' autoload :CompressedMemCacheStore, 'active_support/cache/compressed_mem_cache_store' + EMPTY_OPTIONS = {}.freeze + + # These options mean something to all cache implementations. Individual cache + # implementations may support additional optons. + UNIVERSAL_OPTIONS = [:namespace, :compress, :compress_threshold, :expires_in, :race_condition_ttl] + module Strategy autoload :LocalCache, 'active_support/cache/strategy/local_cache' end @@ -59,15 +69,12 @@ module ActiveSupport end end - RAILS_CACHE_ID = ENV["RAILS_CACHE_ID"] - RAILS_APP_VERION = ENV["RAILS_APP_VERION"] - EXPANDED_CACHE = RAILS_CACHE_ID || RAILS_APP_VERION - def self.expand_cache_key(key, namespace = nil) expanded_cache_key = namespace ? "#{namespace}/" : "" - if EXPANDED_CACHE - expanded_cache_key << "#{RAILS_CACHE_ID || RAILS_APP_VERION}/" + prefix = ENV["RAILS_CACHE_ID"] || ENV["RAILS_APP_VERSION"] + if prefix + expanded_cache_key << "#{prefix}/" end expanded_cache_key << @@ -92,26 +99,75 @@ module ActiveSupport # ActiveSupport::Cache::MemCacheStore. MemCacheStore is currently the most # popular cache store for large production websites. # - # ActiveSupport::Cache::Store is meant for caching strings. Some cache - # store implementations, like MemoryStore, are able to cache arbitrary - # Ruby objects, but don't count on every cache store to be able to do that. + # Some implementations may not support all methods beyond the basic cache + # methods of +fetch+, +write+, +read+, +exist?+, and +delete+. + # + # ActiveSupport::Cache::Store can store any serializable Ruby object. # # cache = ActiveSupport::Cache::MemoryStore.new # # cache.read("city") # => nil # cache.write("city", "Duckburgh") # cache.read("city") # => "Duckburgh" + # + # Keys are always translated into Strings and are case sensitive. When an + # object is specified as a key, its +cache_key+ method will be called if it + # is defined. Otherwise, the +to_param+ method will be called. Hashes and + # Arrays can be used as keys. The elements will be delimited by slashes + # and Hashes elements will be sorted by key so they are consistent. + # + # cache.read("city") == cache.read(:city) # => true + # + # Nil values can be cached. + # + # If your cache is on a shared infrastructure, you can define a namespace for + # your cache entries. If a namespace is defined, it will be prefixed on to every + # key. The namespace can be either a static value or a Proc. If it is a Proc, it + # will be invoked when each key is evaluated so that you can use application logic + # to invalidate keys. + # + # cache.namespace = lambda { @last_mod_time } # Set the namespace to a variable + # @last_mod_time = Time.now # Invalidate the entire cache by changing namespace + # + # All caches support auto expiring content after a specified number of seconds. + # To set the cache entry time to live, you can either specify +:expires_in+ as + # an option to the constructor to have it affect all entries or to the +fetch+ + # or +write+ methods for just one entry. + # + # cache = ActiveSupport::Cache::MemoryStore.new(:expire_in => 5.minutes) + # cache.write(key, value, :expire_in => 1.minute) # Set a lower value for one entry + # + # Caches can also store values in a compressed format to save space and reduce + # time spent sending data. Since there is some overhead, values must be large + # enough to warrant compression. To turn on compression either pass + # <tt>:compress => true</tt> in the initializer or to +fetch+ or +write+. + # To specify the threshold at which to compress values, set + # <tt>:compress_threshold</tt>. The default threshold is 32K. class Store - cattr_accessor :logger, :instance_writter => false + + cattr_accessor :logger, :instance_writer => true attr_reader :silence alias :silence? :silence + # Create a new cache. The options will be passed to any write method calls except + # for :namespace which can be used to set the global namespace for the cache. + def initialize (options = nil) + @options = options ? options.dup : {} + end + + # Get the default options set when the cache was created. + def options + @options ||= {} + end + + # Silence the logger. def silence! @silence = true self end + # Silence the logger within a block. def mute previous_silence, @silence = defined?(@silence) && @silence, true yield @@ -152,28 +208,85 @@ module ActiveSupport # cache.write("today", "Monday") # cache.fetch("today", :force => true) # => nil # + # Setting <tt>:compress</tt> will store a large cache entry set by the call + # in a compressed format. + # + # Setting <tt>:expires_in</tt> will set an expiration time on the cache + # entry if it is set by call. + # + # Setting <tt>:race_condition_ttl</tt> will invoke logic on entries set with + # an <tt>:expires_in</tt> option. If an entry is found in the cache that is + # expired and it has been expired for less than the number of seconds specified + # by this option and a block was passed to the method call, then the expiration + # future time of the entry in the cache will be updated to that many seconds + # in the and the block will be evaluated and written to the cache. + # + # This is very useful in situations where a cache entry is used very frequently + # under heavy load. The first process to find an expired cache entry will then + # become responsible for regenerating that entry while other processes continue + # to use the slightly out of date entry. This can prevent race conditions where + # too many processes are trying to regenerate the entry all at once. If the + # process regenerating the entry errors out, the entry will be regenerated + # after the specified number of seconds. + # + # # Set all values to expire after one minute. + # cache = ActiveSupport::Cache::MemoryCache.new(:expires_in => 1.minute) + # + # cache.write("foo", "original value") + # val_1 = nil + # val_2 = nil + # sleep 60 + # + # Thread.new do + # val_1 = cache.fetch("foo", :race_condition_ttl => 10) do + # sleep 1 + # "new value 1" + # end + # end + # + # Thread.new do + # val_2 = cache.fetch("foo", :race_condition_ttl => 10) do + # "new value 2" + # end + # end + # + # # val_1 => "new value 1" + # # val_2 => "original value" + # # cache.fetch("foo") => "new value 1" + # # Other options will be handled by the specific cache store implementation. - # Internally, #fetch calls #read, and calls #write on a cache miss. + # Internally, #fetch calls #read_entry, and calls #write_entry on a cache miss. # +options+ will be passed to the #read and #write calls. # - # For example, MemCacheStore's #write method supports the +:expires_in+ - # option, which tells the memcached server to automatically expire the - # cache item after a certain period. This options is also supported by - # FileStore's #read method. We can use this option with #fetch too: + # For example, MemCacheStore's #write method supports the +:raw+ + # option, which tells the memcached server to store all values as strings. + # We can use this option with #fetch too: # # cache = ActiveSupport::Cache::MemCacheStore.new - # cache.fetch("foo", :force => true, :expires_in => 5.seconds) do - # "bar" + # cache.fetch("foo", :force => true, :raw => true) do + # :bar # end # cache.fetch("foo") # => "bar" - # sleep(6) - # cache.fetch("foo") # => nil - def fetch(key, options = {}, &block) - if !options[:force] && value = read(key, options) - value + def fetch(name, options = nil, &block) + options = merged_options(options) + key = namespaced_key(name, options) + entry = instrument(:read, name, options) { read_entry(key, options) } unless options[:force] + if entry && entry.expired? + race_ttl = options[:race_condition_ttl].to_f + if race_ttl and Time.now.to_f - entry.expires_at <= race_ttl + entry.expires_at = Time.now + race_ttl + write_entry(key, entry, :expires_in => race_ttl * 2) + else + delete_entry(key, options) + end + entry = nil + end + + if entry + entry.value elsif block_given? - result = instrument(:generate, key, options, &block) - write(key, result, options) + result = instrument(:generate, name, options, &block) + write(name, result, options) result end end @@ -182,15 +295,47 @@ module ActiveSupport # the cache with the given key, then that data is returned. Otherwise, # nil is returned. # - # You may also specify additional options via the +options+ argument. - # The specific cache store implementation will decide what to do with - # +options+. + # Options are passed to the underlying cache implementation. + def read(name, options = nil) + options = merged_options(options) + key = namespaced_key(name, options) + instrument(:read, name, options) do + entry = read_entry(key, options) + if entry + if entry.expired? + delete_entry(key, options) + nil + else + entry.value + end + else + nil + end + end + end + + # Read multiple values at once from the cache. Options can be passed + # in the last argument. # - # For example, FileStore supports the +:expires_in+ option, which - # makes the method return nil for cache items older than the specified - # period. - def read(key, options = nil, &block) - instrument(:read, key, options, &block) + # Some cache implementation may optimize this method. + # + # Returns a hash mapping the names provided to the values found. + def read_multi(*names) + options = names.extract_options! + options = merged_options(options) + results = {} + names.each do |name| + key = namespaced_key(name, options) + entry = read_entry(key, options) + if entry + if entry.expired? + delete_entry(key) + else + results[name] = entry.value + end + end + end + results end # Writes the given value to the cache, with the given key. @@ -198,56 +343,160 @@ module ActiveSupport # You may also specify additional options via the +options+ argument. # The specific cache store implementation will decide what to do with # +options+. + def write(name, value, options = nil) + options = merged_options(options) + instrument(:write, name, options) do + entry = Entry.new(value, options) + write_entry(namespaced_key(name, options), entry, options) + end + end + + # Delete an entry in the cache. Returns +true+ if there was an entry to delete. # - # For example, MemCacheStore supports the +:expires_in+ option, which - # tells the memcached server to automatically expire the cache item after - # a certain period: + # Options are passed to the underlying cache implementation. + def delete(name, options = nil) + options = merged_options(options) + instrument(:delete, name) do + delete_entry(namespaced_key(name, options), options) + end + end + + # Return true if the cache contains an entry with this name. # - # cache = ActiveSupport::Cache::MemCacheStore.new - # cache.write("foo", "bar", :expires_in => 5.seconds) - # cache.read("foo") # => "bar" - # sleep(6) - # cache.read("foo") # => nil - def write(key, value, options = nil, &block) - instrument(:write, key, options, &block) + # Options are passed to the underlying cache implementation. + def exist?(name, options = nil) + options = merged_options(options) + instrument(:exist?, name) do + entry = read_entry(namespaced_key(name, options), options) + if entry && !entry.expired? + true + else + false + end + end end - def delete(key, options = nil, &block) - instrument(:delete, key, options, &block) + # Delete all entries whose keys match a pattern. + # + # Options are passed to the underlying cache implementation. + # + # Not all implementations may support +delete_matched+. + def delete_matched(matcher, options = nil) + raise NotImplementedError.new("#{self.class.name} does not support delete_matched") end - def delete_matched(matcher, options = nil, &block) - instrument(:delete_matched, matcher.inspect, options, &block) + # Increment an integer value in the cache. + # + # Options are passed to the underlying cache implementation. + # + # Not all implementations may support +delete_matched+. + def increment(name, amount = 1, options = nil) + raise NotImplementedError.new("#{self.class.name} does not support increment") end - def exist?(key, options = nil, &block) - instrument(:exist?, key, options, &block) + # Increment an integer value in the cache. + # + # Options are passed to the underlying cache implementation. + # + # Not all implementations may support +delete_matched+. + def decrement(name, amount = 1, options = nil) + raise NotImplementedError.new("#{self.class.name} does not support decrement") end - def increment(key, amount = 1) - if num = read(key) - write(key, num + amount) - else - nil - end + # Cleanup the cache by removing expired entries. Not all cache implementations may + # support this method. + # + # Options are passed to the underlying cache implementation. + # + # Not all implementations may support +delete_matched+. + def cleanup(options = nil) + raise NotImplementedError.new("#{self.class.name} does not support cleanup") end - def decrement(key, amount = 1) - if num = read(key) - write(key, num - amount) - else - nil - end + # Clear the entire cache. Not all cache implementations may support this method. + # You should be careful with this method since it could affect other processes + # if you are using a shared cache. + # + # Options are passed to the underlying cache implementation. + # + # Not all implementations may support +delete_matched+. + def clear(options = nil) + raise NotImplementedError.new("#{self.class.name} does not support clear") end + protected + # Add the namespace defined in the options to a pattern designed to match keys. + # Implementations that support delete_matched should call this method to translate + # a pattern that matches names into one that matches namespaced keys. + def key_matcher(pattern, options) + prefix = options[:namespace].is_a?(Proc) ? options[:namespace].call : options[:namespace] + if prefix + source = pattern.source + if source.start_with?('^') + source = source[1, source.length] + else + source = ".*#{source[0, source.length]}" + end + Regexp.new("^#{Regexp.escape(prefix)}:#{source}", pattern.options) + else + pattern + end + end + + # Read an entry from the cache implementation. Subclasses must implement this method. + def read_entry(key, options) # :nodoc: + raise NotImplementedError.new + end + + # Write an entry to the cache implementation. Subclasses must implement this method. + def write_entry(key, entry, options) # :nodoc: + raise NotImplementedError.new + end + + # Delete an entry from the cache implementation. Subclasses must implement this method. + def delete_entry(key, options) # :nodoc: + raise NotImplementedError.new + end + private - def expires_in(options) - expires_in = options && options[:expires_in] - raise ":expires_in must be a number" if expires_in && !expires_in.is_a?(Numeric) - expires_in || 0 + # Merge the default options with ones specific to a method call. + def merged_options(call_options) # :nodoc: + if call_options + options.merge(call_options) + else + options.dup + end + end + + # Expand a key to be a consistent string value. If the object responds to +cache_key+, + # it will be called. Otherwise, the to_param method will be called. If the key is a + # Hash, the keys will be sorted alphabetically. + def expanded_key(key) # :nodoc: + if key.respond_to?(:cache_key) + key = key.cache_key.to_s + elsif key.is_a?(Array) + if key.size > 1 + key.collect{|element| expanded_key(element)}.to_param + else + key.first.to_param + end + elsif key.is_a?(Hash) + key = key.to_a.sort{|a,b| a.first.to_s <=> b.first.to_s}.collect{|k,v| "#{k}=#{v}"}.to_param + else + key = key.to_param + end + end + + # Prefix a key with the namespace. The two values will be delimited with a colon. + def namespaced_key(key, options) + key = expanded_key(key) + namespace = options[:namespace] if options + prefix = namespace.is_a?(Proc) ? namespace.call : namespace + key = "#{prefix}:#{key}" if prefix + key end - def instrument(operation, key, options) + def instrument(operation, key, options = nil) log(operation, key, options) if self.class.instrument @@ -259,9 +508,118 @@ module ActiveSupport end end - def log(operation, key, options) - return unless logger && !silence? - logger.debug("Cache #{operation}: #{key}#{options ? " (#{options.inspect})" : ""}") + def log(operation, key, options = nil) + return unless logger && logger.debug? && !silence? + logger.debug("Cache #{operation}: #{key}#{options.blank? ? "" : " (#{options.inspect})"}") + end + end + + # Entry that is put into caches. It supports expiration time on entries and can compress values + # to save space in the cache. + class Entry + attr_reader :created_at, :expires_in + + DEFAULT_COMPRESS_LIMIT = 16.kilobytes + + class << self + # Create an entry with internal attributes set. This method is intended to be + # used by implementations that store cache entries in a native format instead + # of as serialized Ruby objects. + def create (raw_value, created_at, options = {}) + entry = new(nil) + entry.instance_variable_set(:@value, raw_value) + entry.instance_variable_set(:@created_at, created_at.to_f) + entry.instance_variable_set(:@compressed, !!options[:compressed]) + entry.instance_variable_set(:@expires_in, options[:expires_in]) + entry + end + end + + # Create a new cache entry for the specified value. Options supported are + # +:compress+, +:compress_threshold+, and +:expires_in+. + def initialize(value, options = {}) + @compressed = false + @expires_in = options[:expires_in] + @expires_in = @expires_in.to_f if @expires_in + @created_at = Time.now.to_f + if value + if should_compress?(value, options) + @value = Zlib::Deflate.deflate(Marshal.dump(value)) + @compressed = true + else + @value = value + end + else + @value = nil + end + end + + # Get the raw value. This value may be serialized and compressed. + def raw_value + @value + end + + # Get the value stored in the cache. + def value + if @value + val = compressed? ? Marshal.load(Zlib::Inflate.inflate(@value)) : @value + unless val.frozen? + val.freeze rescue nil + end + val + end + end + + def compressed? + @compressed + end + + # Check if the entry is expired. The +expires_in+ parameter can override the + # value set when the entry was created. + def expired? + if @expires_in && @created_at + @expires_in <= Time.now.to_f + true + else + false + end + end + + # Set a new time to live on the entry so it expires at the given time. + def expires_at=(time) + if time + @expires_in = time.to_f - @created_at + else + @expires_in = nil + end + end + + # Seconds since the epoch when the cache entry will expire. + def expires_at + @expires_in ? @created_at + @expires_in : nil + end + + # Get the size of the cached value. This could be less than value.size + # if the data is compressed. + def size + if @value.nil? + 0 + elsif @value.respond_to?(:bytesize) + @value.bytesize + else + Marshal.dump(@value).bytesize + end + end + + private + def should_compress?(value, options) + if options[:compress] && value + unless value.is_a?(Numeric) + compress_threshold = options[:compress_threshold] || DEFAULT_COMPRESS_LIMIT + serialized_value = value.is_a?(String) ? value : Marshal.dump(value) + return true if serialized_value.size >= compress_threshold + end + end + false end end end diff --git a/activesupport/lib/active_support/cache/compressed_mem_cache_store.rb b/activesupport/lib/active_support/cache/compressed_mem_cache_store.rb index d2370d78c5..7c7d1c4b00 100644 --- a/activesupport/lib/active_support/cache/compressed_mem_cache_store.rb +++ b/activesupport/lib/active_support/cache/compressed_mem_cache_store.rb @@ -1,21 +1,12 @@ -require 'active_support/gzip' - module ActiveSupport module Cache class CompressedMemCacheStore < MemCacheStore - def read(name, options = nil) - if value = super(name, (options || {}).merge(:raw => true)) - if raw?(options) - value - else - Marshal.load(ActiveSupport::Gzip.decompress(value)) - end - end - end - - def write(name, value, options = nil) - value = ActiveSupport::Gzip.compress(Marshal.dump(value)) unless raw?(options) - super(name, value, (options || {}).merge(:raw => true)) + def initialize(*args) + ActiveSupport::Deprecation.warn('ActiveSupport::Cache::CompressedMemCacheStore has been deprecated in favor of ActiveSupport::Cache::MemCacheStore(:compress => true).', caller) + addresses = args.dup + options = addresses.extract_options! + args = addresses + [options.merge(:compress => true)] + super(*args) end end end diff --git a/activesupport/lib/active_support/cache/file_store.rb b/activesupport/lib/active_support/cache/file_store.rb index 7521efe7c5..fc225e77a2 100644 --- a/activesupport/lib/active_support/cache/file_store.rb +++ b/activesupport/lib/active_support/cache/file_store.rb @@ -3,73 +3,171 @@ require 'active_support/core_ext/file/atomic' module ActiveSupport module Cache # A cache store implementation which stores everything on the filesystem. + # + # FileStore implements the Strategy::LocalCache strategy which implements + # an in memory cache inside of a block. class FileStore < Store attr_reader :cache_path - def initialize(cache_path) + DIR_FORMATTER = "%03X" + ESCAPE_FILENAME_CHARS = /[^a-z0-9_.-]/i + UNESCAPE_FILENAME_CHARS = /%[0-9A-F]{2}/ + + def initialize(cache_path, options = nil) + super(options) @cache_path = cache_path + extend Strategy::LocalCache end - # Reads a value from the cache. - # - # Possible options: - # - +:expires_in+ - the number of seconds that this value may stay in - # the cache. - def read(name, options = nil) - super do - file_name = real_file_path(name) - expires = expires_in(options) - - if File.exist?(file_name) && (expires <= 0 || Time.now - File.mtime(file_name) < expires) - File.open(file_name, 'rb') { |f| Marshal.load(f) } - end + def clear(options = nil) + root_dirs = Dir.entries(cache_path).reject{|f| ['.', '..'].include?(f)} + FileUtils.rm_r(root_dirs.collect{|f| File.join(cache_path, f)}) + end + + def cleanup(options = nil) + options = merged_options(options) + each_key(options) do |key| + entry = read_entry(key, options) + delete_entry(key, options) if entry && entry.expired? end end - # Writes a value to the cache. - def write(name, value, options = nil) - super do - ensure_cache_path(File.dirname(real_file_path(name))) - File.atomic_write(real_file_path(name), cache_path) { |f| Marshal.dump(value, f) } - value + def increment(name, amount = 1, options = nil) + file_name = key_file_path(namespaced_key(name, options)) + lock_file(file_name) do + options = merged_options(options) + if num = read(name, options) + num = num.to_i + amount + write(name, num, options) + num + else + nil + end end - rescue => e - logger.error "Couldn't create cache directory: #{name} (#{e.message})" if logger end - def delete(name, options = nil) - super do - File.delete(real_file_path(name)) + def decrement(name, amount = 1, options = nil) + file_name = key_file_path(namespaced_key(name, options)) + lock_file(file_name) do + options = merged_options(options) + if num = read(name, options) + num = num.to_i - amount + write(name, num, options) + num + else + nil + end end - rescue SystemCallError => e - # If there's no cache, then there's nothing to complain about end def delete_matched(matcher, options = nil) - super do - search_dir(@cache_path) do |f| - if f =~ matcher - begin - File.delete(f) - rescue SystemCallError => e - # If there's no cache, then there's nothing to complain about + options = merged_options(options) + instrument(:delete_matched, matcher.inspect) do + matcher = key_matcher(matcher, options) + search_dir(cache_path) do |path| + key = file_path_key(path) + delete_entry(key, options) if key.match(matcher) + end + end + end + + protected + + def read_entry(key, options) + file_name = key_file_path(key) + if File.exist?(file_name) + entry = File.open(file_name) { |f| Marshal.load(f) } + if entry && !entry.expired? && !entry.expires_in && !self.options[:expires_in] + # Check for deprecated use of +:expires_in+ option from versions < 3.0 + deprecated_expires_in = options[:expires_in] + if deprecated_expires_in + ActiveSupport::Deprecation.warn('Setting :expires_in on read has been deprecated in favor of setting it on write.', caller) + if entry.created_at + deprecated_expires_in.to_f <= Time.now.to_f + delete_entry(key, options) + entry = nil + end end end + entry end + rescue + nil end - end - def exist?(name, options = nil) - super do - File.exist?(real_file_path(name)) + def write_entry(key, entry, options) + file_name = key_file_path(key) + ensure_cache_path(File.dirname(file_name)) + File.atomic_write(file_name, cache_path) {|f| Marshal.dump(entry, f)} + true + end + + def delete_entry(key, options) + file_name = key_file_path(key) + if File.exist?(file_name) + begin + File.delete(file_name) + delete_empty_directories(File.dirname(file_name)) + true + rescue => e + # Just in case the error was caused by another process deleting the file first. + raise e if File.exist?(file_name) + false + end + end end - end private - def real_file_path(name) - '%s/%s.cache' % [@cache_path, name.gsub('?', '.').gsub(':', '.')] + # Lock a file for a block so only one process can modify it at a time. + def lock_file(file_name, &block) # :nodoc: + if File.exist?(file_name) + File.open(file_name, 'r') do |f| + begin + f.flock File::LOCK_EX + yield + ensure + f.flock File::LOCK_UN + end + end + else + yield + end + end + + # Translate a key into a file path. + def key_file_path(key) + fname = key.to_s.gsub(ESCAPE_FILENAME_CHARS){|match| "%#{match.ord.to_s(16).upcase}"} + hash = Zlib.adler32(fname) + hash, dir_1 = hash.divmod(0x1000) + dir_2 = hash.modulo(0x1000) + fname_paths = [] + # Make sure file name is < 255 characters so it doesn't exceed file system limits. + if fname.size <= 255 + fname_paths << fname + else + while fname.size <= 255 + fname_path << fname[0, 255] + fname = fname[255, -1] + end + end + File.join(cache_path, DIR_FORMATTER % dir_1, DIR_FORMATTER % dir_2, *fname_paths) + end + + # Translate a file path into a key. + def file_path_key(path) + fname = path[cache_path.size, path.size].split(File::SEPARATOR, 4).last + fname.gsub(UNESCAPE_FILENAME_CHARS){|match| $1.ord.to_s(16)} + end + + # Delete empty directories in the cache. + def delete_empty_directories(dir) + return if dir == cache_path + if Dir.entries(dir).reject{|f| ['.', '..'].include?(f)}.empty? + File.delete(dir) rescue nil + delete_empty_directories(File.dirname(dir)) + end end + # Make sure a file path's directories exist. def ensure_cache_path(path) FileUtils.makedirs(path) unless File.exist?(path) end diff --git a/activesupport/lib/active_support/cache/mem_cache_store.rb b/activesupport/lib/active_support/cache/mem_cache_store.rb index c56fedc12e..d8377a208f 100644 --- a/activesupport/lib/active_support/cache/mem_cache_store.rb +++ b/activesupport/lib/active_support/cache/mem_cache_store.rb @@ -1,5 +1,5 @@ require 'memcache' -require 'active_support/core_ext/array/extract_options' +require 'digest/md5' module ActiveSupport module Cache @@ -13,8 +13,9 @@ module ActiveSupport # and MemCacheStore will load balance between all available servers. If a # server goes down, then MemCacheStore will ignore it until it goes back # online. - # - Time-based expiry support. See #write and the <tt>:expires_in</tt> option. - # - Per-request in memory cache for all communication with the MemCache server(s). + # + # MemCacheStore implements the Strategy::LocalCache strategy which implements + # an in memory cache inside of a block. class MemCacheStore < Store module Response # :nodoc: STORED = "STORED\r\n" @@ -24,6 +25,8 @@ module ActiveSupport DELETED = "DELETED\r\n" end + ESCAPE_KEY_CHARS = /[\x00-\x20%\x7F-\xFF]/ + def self.build_mem_cache(*addresses) addresses = addresses.flatten options = addresses.extract_options! @@ -45,108 +48,139 @@ module ActiveSupport # require 'memcached' # gem install memcached; uses C bindings to libmemcached # ActiveSupport::Cache::MemCacheStore.new(Memcached::Rails.new("localhost:11211")) def initialize(*addresses) + addresses = addresses.flatten + options = addresses.extract_options! + super(options) + if addresses.first.respond_to?(:get) @data = addresses.first else - @data = self.class.build_mem_cache(*addresses) + mem_cache_options = options.dup + UNIVERSAL_OPTIONS.each{|name| mem_cache_options.delete(name)} + @data = self.class.build_mem_cache(*(addresses + [mem_cache_options])) end extend Strategy::LocalCache + extend LocalCacheWithRaw end - # Reads multiple keys from the cache. - def read_multi(*keys) - @data.get_multi keys - end - - def read(key, options = nil) # :nodoc: - super do - @data.get(key, raw?(options)) - end - rescue MemCache::MemCacheError => e - logger.error("MemCacheError (#{e}): #{e.message}") if logger - nil - end - - # Writes a value to the cache. - # - # Possible options: - # - <tt>:unless_exist</tt> - set to true if you don't want to update the cache - # if the key is already set. - # - <tt>:expires_in</tt> - the number of seconds that this value may stay in - # the cache. See ActiveSupport::Cache::Store#write for an example. - def write(key, value, options = nil) - super do - method = options && options[:unless_exist] ? :add : :set - # memcache-client will break the connection if you send it an integer - # in raw mode, so we convert it to a string to be sure it continues working. - value = value.to_s if raw?(options) - response = @data.send(method, key, value, expires_in(options), raw?(options)) - response == Response::STORED - end - rescue MemCache::MemCacheError => e - logger.error("MemCacheError (#{e}): #{e.message}") if logger - false - end - - def delete(key, options = nil) # :nodoc: - super do - response = @data.delete(key) - response == Response::DELETED - end - rescue MemCache::MemCacheError => e - logger.error("MemCacheError (#{e}): #{e.message}") if logger - false - end - - def exist?(key, options = nil) # :nodoc: - # Doesn't call super, cause exist? in memcache is in fact a read - # But who cares? Reading is very fast anyway - # Local cache is checked first, if it doesn't know then memcache itself is read from - super do - !read(key, options).nil? + # Reads multiple keys from the cache using a single call to the + # servers for all keys. Options can be passed in the last argument. + def read_multi(*names) + options = names.extract_options! + options = merged_options(options) + keys_to_names = names.inject({}){|map, name| map[escape_key(namespaced_key(name, options))] = name; map} + raw_values = @data.get_multi(keys_to_names.keys, :raw => true) + values = {} + raw_values.each do |key, value| + entry = deserialize_entry(value) + values[keys_to_names[key]] = entry.value unless entry.expired? end + values end - def increment(key, amount = 1) # :nodoc: - response = instrument(:increment, key, :amount => amount) do - @data.incr(key, amount) + # Increment a cached value. This method uses the memcached incr atomic + # operator and can only be used on values written with the :raw option. + # Calling it on a value not stored with :raw will initialize that value + # to zero. + def increment(name, amount = 1, options = nil) # :nodoc: + options = merged_options(options) + response = instrument(:increment, name, :amount => amount) do + @data.incr(escape_key(namespaced_key(name, options)), amount) end - - response == Response::NOT_FOUND ? nil : response + response == Response::NOT_FOUND ? nil : response.to_i rescue MemCache::MemCacheError nil end - def decrement(key, amount = 1) # :nodoc: - response = instrument(:decrement, key, :amount => amount) do - @data.decr(key, amount) + # Decrement a cached value. This method uses the memcached decr atomic + # operator and can only be used on values written with the :raw option. + # Calling it on a value not stored with :raw will initialize that value + # to zero. + def decrement(name, amount = 1, options = nil) # :nodoc: + options = merged_options(options) + response = instrument(:decrement, name, :amount => amount) do + @data.decr(escape_key(namespaced_key(name, options)), amount) end - - response == Response::NOT_FOUND ? nil : response + response == Response::NOT_FOUND ? nil : response.to_i rescue MemCache::MemCacheError nil end - def delete_matched(matcher, options = nil) # :nodoc: - # don't do any local caching at present, just pass - # through and let the error happen - super - raise "Not supported by Memcache" - end - - def clear + # Clear the entire cache on all memcached servers. This method should + # be used with care when using a shared cache. + def clear(options = nil) @data.flush_all end + # Get the statistics from the memcached servers. def stats @data.stats end + protected + # Read an entry from the cache. + def read_entry(key, options) # :nodoc: + deserialize_entry(@data.get(escape_key(key), true)) + rescue MemCache::MemCacheError => e + logger.error("MemCacheError (#{e}): #{e.message}") if logger + nil + end + + # Write an entry to the cache. + def write_entry(key, entry, options) # :nodoc: + method = options && options[:unless_exist] ? :add : :set + value = options[:raw] ? entry.value.to_s : entry + expires_in = options[:expires_in].to_i + if expires_in > 0 && !options[:raw] + # Set the memcache expire a few minutes in the future to support race condition ttls on read + expires_in += 5.minutes + end + response = @data.send(method, escape_key(key), value, expires_in, options[:raw]) + response == Response::STORED + rescue MemCache::MemCacheError => e + logger.error("MemCacheError (#{e}): #{e.message}") if logger + false + end + + # Delete an entry from the cache. + def delete_entry(key, options) # :nodoc: + response = @data.delete(escape_key(key)) + response == Response::DELETED + rescue MemCache::MemCacheError => e + logger.error("MemCacheError (#{e}): #{e.message}") if logger + false + end + private - def raw?(options) - options && options[:raw] + def escape_key(key) + key = key.to_s.gsub(ESCAPE_KEY_CHARS){|match| "%#{match[0].to_s(16).upcase}"} + key = "#{key[0, 213]}:md5:#{Digest::MD5.hexdigest(key)}" if key.size > 250 + key end + + def deserialize_entry(raw_value) + if raw_value + entry = Marshal.load(raw_value) rescue raw_value + entry.is_a?(Entry) ? entry : Entry.new(entry) + else + nil + end + end + + # Provide support for raw values in the local cache strategy. + module LocalCacheWithRaw # :nodoc: + protected + def write_entry(key, entry, options) # :nodoc: + retval = super + if options[:raw] && local_cache && retval + raw_entry = Entry.new(entry.value.to_s) + raw_entry.expires_at = entry.expires_at + local_cache.write_entry(key, raw_entry, options) + end + retval + end + end end end end diff --git a/activesupport/lib/active_support/cache/memory_store.rb b/activesupport/lib/active_support/cache/memory_store.rb index 379922f986..b1d14a0d8f 100644 --- a/activesupport/lib/active_support/cache/memory_store.rb +++ b/activesupport/lib/active_support/cache/memory_store.rb @@ -1,4 +1,4 @@ -require 'active_support/core_ext/object/duplicable' +require 'monitor' module ActiveSupport module Cache @@ -6,60 +6,154 @@ module ActiveSupport # same process. If you're running multiple Ruby on Rails server processes # (which is the case if you're using mongrel_cluster or Phusion Passenger), # then this means that your Rails server process instances won't be able - # to share cache data with each other. If your application never performs - # manual cache item expiry (e.g. when you're using generational cache keys), - # then using MemoryStore is ok. Otherwise, consider carefully whether you - # should be using this cache store. + # to share cache data with each other and this may not be the most + # appropriate cache for you. # - # MemoryStore is not only able to store strings, but also arbitrary Ruby - # objects. + # This cache has a bounded size specified by the :size options to the + # initializer (default is 32Mb). When the cache exceeds the alotted size, + # a cleanup will occur which tries to prune the cache down to three quarters + # of the maximum size by removing the least recently used entries. # - # MemoryStore is not thread-safe. Use SynchronizedMemoryStore instead - # if you need thread-safety. + # MemoryStore is thread-safe. class MemoryStore < Store - def initialize + def initialize(options = nil) + options ||= {} + super(options) @data = {} + @key_access = {} + @max_size = options[:size] || 32.megabytes + @max_prune_time = options[:max_prune_time] || 2 + @cache_size = 0 + @monitor = Monitor.new + @pruning = false end - def read_multi(*names) - results = {} - names.each { |n| results[n] = read(n) } - results + def clear(options = nil) + synchronize do + @data.clear + @key_access.clear + @cache_size = 0 + end end - def read(name, options = nil) - super do - @data[name] + def cleanup(options = nil) + options = merged_options(options) + instrument(:cleanup, :size => @data.size) do + keys = synchronize{ @data.keys } + keys.each do |key| + entry = @data[key] + delete_entry(key, options) if entry && entry.expired? + end end end - def write(name, value, options = nil) - super do - @data[name] = (value.duplicable? ? value.dup : value).freeze + # Prune the cache down so the entries fit within the specified memory size by removing + # the least recently accessed entries. + def prune(target_size, max_time = nil) + return if pruning? + @pruning = true + begin + start_time = Time.now + cleanup + instrument(:prune, target_size, :from => @cache_size) do + keys = synchronize{ @key_access.keys.sort{|a,b| @key_access[a].to_f <=> @key_access[b].to_f} } + keys.each do |key| + delete_entry(key, options) + return if @cache_size <= target_size || (max_time && Time.now - start_time > max_time) + end + end + ensure + @pruning = false end end - def delete(name, options = nil) - super do - @data.delete(name) + # Return true if the cache is currently be pruned to remove older entries. + def pruning? + @pruning + end + + # Increment an integer value in the cache. + def increment(name, amount = 1, options = nil) + synchronize do + options = merged_options(options) + if num = read(name, options) + num = num.to_i + amount + write(name, num, options) + num + else + nil + end end end - def delete_matched(matcher, options = nil) - super do - @data.delete_if { |k,v| k =~ matcher } + # Decrement an integer value in the cache. + def decrement(name, amount = 1, options = nil) + synchronize do + options = merged_options(options) + if num = read(name, options) + num = num.to_i - amount + write(name, num, options) + num + else + nil + end end end - def exist?(name, options = nil) - super do - @data.has_key?(name) + def delete_matched(matcher, options = nil) + options = merged_options(options) + instrument(:delete_matched, matcher.inspect) do + matcher = key_matcher(matcher, options) + keys = synchronize { @data.keys } + keys.each do |key| + delete_entry(key, options) if key.match(matcher) + end end end - def clear - @data.clear + def inspect # :nodoc: + "<##{self.class.name} entries=#{@data.size}, size=#{@cache_size}, options=#{@options.inspect}>" + end + + # Synchronize calls to the cache. This should be called wherever the underlying cache implementation + # is not thread safe. + def synchronize(&block) # :nodoc: + @monitor.synchronize(&block) end + + protected + def read_entry(key, options) # :nodoc: + entry = @data[key] + synchronize do + if entry + @key_access[key] = Time.now.to_f + else + @key_access.delete(key) + end + end + entry + end + + def write_entry(key, entry, options) # :nodoc: + synchronize do + old_entry = @data[key] + @cache_size -= old_entry.size if old_entry + @cache_size += entry.size + @key_access[key] = Time.now.to_f + @data[key] = entry + prune(@max_size * 0.75, @max_prune_time) if @cache_size > @max_size + true + end + end + + def delete_entry(key, options) # :nodoc: + synchronize do + @key_access.delete(key) + entry = @data.delete(key) + @cache_size -= entry.size if entry + !!entry + end + end end end end diff --git a/activesupport/lib/active_support/cache/strategy/local_cache.rb b/activesupport/lib/active_support/cache/strategy/local_cache.rb index bbbd643736..8942587ac8 100644 --- a/activesupport/lib/active_support/cache/strategy/local_cache.rb +++ b/activesupport/lib/active_support/cache/strategy/local_cache.rb @@ -4,17 +4,54 @@ require 'active_support/core_ext/string/inflections' module ActiveSupport module Cache module Strategy + # Caches that implement LocalCache will be backed by an in memory cache for the + # duration of a block. Repeated calls to the cache for the same key will hit the + # in memory cache for faster access. module LocalCache - # this allows caching of the fact that there is nothing in the remote cache - NULL = 'remote_cache_store:null' + # Simple memory backed cache. This cache is not thread safe but is intended only + # for serving as a temporary memory cache for a single thread. + class LocalStore < Store + def initialize + super + @data = {} + end + + # Since it isn't thread safe, don't allow synchronizing. + def synchronize # :nodoc: + yield + end + + def clear(options = nil) + @data.clear + end + + def read_entry(key, options) + @data[key] + end + def write_entry(key, value, options) + @data[key] = value + true + end + + def delete_entry(key, options) + !!@data.delete(key) + end + end + + # Use a local cache to front for the cache for the duration of a block. def with_local_cache - Thread.current[thread_local_key] = MemoryStore.new - yield - ensure - Thread.current[thread_local_key] = nil + save_val = Thread.current[thread_local_key] + begin + Thread.current[thread_local_key] = LocalStore.new + yield + ensure + Thread.current[thread_local_key] = save_val + end end + # Middleware class can be inserted as a Rack handler to use a local cache for the + # duration of a request. def middleware @middleware ||= begin klass = Class.new @@ -24,7 +61,7 @@ module ActiveSupport end def call(env) - Thread.current[:#{thread_local_key}] = MemoryStore.new + Thread.current[:#{thread_local_key}] = LocalStore.new @app.call(env) ensure Thread.current[:#{thread_local_key}] = nil @@ -39,73 +76,86 @@ module ActiveSupport end end - def read(key, options = nil) - value = local_cache && local_cache.read(key) - if value == NULL - nil - elsif value.nil? - value = super - local_cache.mute { local_cache.write(key, value || NULL) } if local_cache - value.duplicable? ? value.dup : value - else - # forcing the value to be immutable - value.duplicable? ? value.dup : value - end - end - - def write(key, value, options = nil) - value = value.to_s if respond_to?(:raw?) && raw?(options) - local_cache.mute { local_cache.write(key, value || NULL) } if local_cache + def clear(options = nil) # :nodoc: + local_cache.clear(options) if local_cache super end - def delete(key, options = nil) - local_cache.mute { local_cache.write(key, NULL) } if local_cache + def cleanup(options = nil) # :nodoc: + local_cache.clear(options) if local_cache super end - def exist(key, options = nil) - value = local_cache.read(key) if local_cache - if value == NULL - false - elsif value - true - else - super + def increment(name, amount = 1, options = nil) # :nodoc: + value = bypass_local_cache{super} + if local_cache + local_cache.mute do + if value + local_cache.write(name, value, options) + else + local_cache.delete(name, options) + end + end end + value end - def increment(key, amount = 1) - if value = super - local_cache.mute { local_cache.write(key, value.to_s) } if local_cache - value - else - nil + def decrement(name, amount = 1, options = nil) # :nodoc: + value = bypass_local_cache{super} + if local_cache + local_cache.mute do + if value + local_cache.write(name, value, options) + else + local_cache.delete(name, options) + end + end end + value end - def decrement(key, amount = 1) - if value = super - local_cache.mute { local_cache.write(key, value.to_s) } if local_cache - value - else - nil + protected + def read_entry(key, options) # :nodoc: + if local_cache + entry = local_cache.read_entry(key, options) + unless entry + entry = super + local_cache.write_entry(key, entry, options) + end + entry + else + super + end end - end - def clear - local_cache.clear if local_cache - super - end + def write_entry(key, entry, options) # :nodoc: + local_cache.write_entry(key, entry, options) if local_cache + super + end + + def delete_entry(key, options) # :nodoc: + local_cache.delete_entry(key, options) if local_cache + super + end private def thread_local_key - @thread_local_key ||= "#{self.class.name.underscore}_local_cache".gsub("/", "_").to_sym + @thread_local_key ||= "#{self.class.name.underscore}_local_cache_#{self.object_id}".gsub("/", "_").to_sym end def local_cache Thread.current[thread_local_key] end + + def bypass_local_cache + save_cache = Thread.current[thread_local_key] + begin + Thread.current[thread_local_key] = nil + yield + ensure + Thread.current[thread_local_key] = save_cache + end + end end end end diff --git a/activesupport/lib/active_support/cache/synchronized_memory_store.rb b/activesupport/lib/active_support/cache/synchronized_memory_store.rb index ea03a119c6..37caa6b6f1 100644 --- a/activesupport/lib/active_support/cache/synchronized_memory_store.rb +++ b/activesupport/lib/active_support/cache/synchronized_memory_store.rb @@ -2,45 +2,9 @@ module ActiveSupport module Cache # Like MemoryStore, but thread-safe. class SynchronizedMemoryStore < MemoryStore - def initialize + def initialize(*args) + ActiveSupport::Deprecation.warn('ActiveSupport::Cache::SynchronizedMemoryStore has been deprecated in favor of ActiveSupport::Cache::MemoryStore.', caller) super - @guard = Monitor.new - end - - def fetch(key, options = {}) - @guard.synchronize { super } - end - - def read(name, options = nil) - @guard.synchronize { super } - end - - def write(name, value, options = nil) - @guard.synchronize { super } - end - - def delete(name, options = nil) - @guard.synchronize { super } - end - - def delete_matched(matcher, options = nil) - @guard.synchronize { super } - end - - def exist?(name,options = nil) - @guard.synchronize { super } - end - - def increment(key, amount = 1) - @guard.synchronize { super } - end - - def decrement(key, amount = 1) - @guard.synchronize { super } - end - - def clear - @guard.synchronize { super } end end end |