diff options
Diffstat (limited to 'activesupport/lib/active_support')
| -rw-r--r-- | activesupport/lib/active_support/cache.rb | 148 | ||||
| -rw-r--r-- | activesupport/lib/active_support/cache/memory_store.rb | 1 |
2 files changed, 86 insertions, 63 deletions
diff --git a/activesupport/lib/active_support/cache.rb b/activesupport/lib/active_support/cache.rb index f98ba16cdd..a681a8d6a9 100644 --- a/activesupport/lib/active_support/cache.rb +++ b/activesupport/lib/active_support/cache.rb @@ -284,7 +284,9 @@ module ActiveSupport end if entry && entry.expired? race_ttl = options[:race_condition_ttl].to_i - if race_ttl and Time.now.to_f - entry.expires_at <= race_ttl + if race_ttl && (Time.now - entry.expires_at <= race_ttl) + # When an entry has :race_condition_ttl defined, put the stale entry back into the cache + # for a brief period while the entry is begin recalculated. entry.expires_at = Time.now + race_ttl write_entry(key, entry, :expires_in => race_ttl * 2) else @@ -532,102 +534,122 @@ module ActiveSupport 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 - + # This class is used to represent cache entries. Cache entries have a value and an optional + # expiration time. The expiration time is used to support the :race_condition_ttl option + # on the cache. + # + # Since cache entries in most instances will be serialized, the internals of this class are highly optimized + # using short instance variable names that are lazily defined. + class Entry # :nodoc: 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.nil? - @value = nil + if should_compress?(value, options) + @v = compress(value) + @c = true else - @value = Marshal.dump(value) - if should_compress?(@value, options) - @value = Zlib::Deflate.deflate(@value) - @compressed = true - end + @v = value 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 the original value was exactly false @value is still true because - # it is marshalled and eventually compressed. Both operations yield - # strings. - if @value - Marshal.load(compressed? ? Zlib::Inflate.inflate(@value) : @value) + if expires_in = options[:expires_in] + @x = (Time.now + expires_in).to_i end end - def compressed? - @compressed + def value + convert_version_3_entry! if defined?(@value) + compressed? ? uncompress(@v) : @v end # Check if the entry is expired. The +expires_in+ parameter can override # the value set when the entry was created. def expired? - @expires_in && @created_at + @expires_in <= Time.now.to_f - end - - # Set a new time when the entry will expire. - def expires_at=(time) - if time - @expires_in = time.to_f - @created_at + convert_version_3_entry! if defined?(@value) + if defined?(@x) + @x && @x < Time.now.to_i else - @expires_in = nil + false end end - # Seconds since the epoch when the entry will expire. def expires_at - @expires_in ? @created_at + @expires_in : nil + Time.at(@x) if defined?(@x) + end + + def expires_at=(value) + @x = value.to_i end # Returns the size of the cached value. This could be less than # <tt>value.size</tt> if the data is compressed. def size - if @value.nil? - 0 + if defined?(@s) + @s else - @value.bytesize + case value + when NilClass + 0 + when String + value.bytesize + else + @s = Marshal.dump(value).bytesize + end + end + end + + # Duplicate the value in a class. This is used by cache implementations that don't natively + # serialize entries to protect against accidental cache modifications. + def dup_value! + convert_version_3_entry! if defined?(@value) + if @v && !compressed? && !(@v.is_a?(Numeric) || @v == true || @v == false) + if @v.is_a?(String) + @v = @v.dup + else + @v = Marshal.load(Marshal.dump(@v)) + end end end private - def should_compress?(serialized_value, options) - if options[:compress] + def should_compress?(value, options) + if value && options[:compress] compress_threshold = options[:compress_threshold] || DEFAULT_COMPRESS_LIMIT - return true if serialized_value.size >= compress_threshold + serialized_value_size = (value.is_a?(String) ? value : Marshal.dump(value)).bytesize + return true if serialized_value_size >= compress_threshold end false end + + def compressed? + defined?(@c) ? @c : false + end + + def compress(value) + Zlib::Deflate.deflate(Marshal.dump(value)) + end + + def uncompress(value) + Marshal.load(Zlib::Inflate.inflate(value)) + end + + # The internals of this method changed between Rails 3.x and 4.0. This method provides the glue + # to ensure that cache entries created under the old version still work with the new class definition. + def convert_version_3_entry! + if defined?(@value) + @v = @value + remove_instance_variable(:@value) + end + if defined?(@compressed) + @c = @compressed + remove_instance_variable(:@compressed) + end + if defined?(@expires_in) && defined?(@created_at) + @x = (@created_at + @expires_in).to_i + remove_instance_variable(:@created_at) + remove_instance_variable(:@expires_in) + 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 7fd5e3b53d..4d26fb7e42 100644 --- a/activesupport/lib/active_support/cache/memory_store.rb +++ b/activesupport/lib/active_support/cache/memory_store.rb @@ -135,6 +135,7 @@ module ActiveSupport end def write_entry(key, entry, options) # :nodoc: + entry.dup_value! synchronize do old_entry = @data[key] return false if @data.key?(key) && options[:unless_exist] |