mirror of
https://github.com/rails/rails.git
synced 2022-11-09 12:12:34 -05:00
25b47c25ba
Same bug as https://github.com/rails/rails/pull/42559, but a very different fix due to https://github.com/rails/rails/pull/42025. To recap, the issue: - While using the `dalli_store`, you set any value in the Rails cache with no expiry. - You change to the `mem_cache_store`. - You upgrade to Rails 7. - You try to read the same cache key you set in step 1, and it crashes on read. https://github.com/rails/rails/pull/42025 was backward compatible with entries written using the `mem_cache_store`, but *not* the `dalli_store` which did not use `ActiveSupport::Cache::Entry`. This PR attempts to fix that.
1022 lines
37 KiB
Ruby
1022 lines
37 KiB
Ruby
# frozen_string_literal: true
|
|
|
|
require "zlib"
|
|
require "active_support/core_ext/array/extract_options"
|
|
require "active_support/core_ext/array/wrap"
|
|
require "active_support/core_ext/enumerable"
|
|
require "active_support/core_ext/module/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/object/try"
|
|
require "active_support/core_ext/string/inflections"
|
|
|
|
module ActiveSupport
|
|
# See ActiveSupport::Cache::Store for documentation.
|
|
module Cache
|
|
autoload :FileStore, "active_support/cache/file_store"
|
|
autoload :MemoryStore, "active_support/cache/memory_store"
|
|
autoload :MemCacheStore, "active_support/cache/mem_cache_store"
|
|
autoload :NullStore, "active_support/cache/null_store"
|
|
autoload :RedisCacheStore, "active_support/cache/redis_cache_store"
|
|
|
|
# These options mean something to all cache implementations. Individual cache
|
|
# implementations may support additional options.
|
|
UNIVERSAL_OPTIONS = [:namespace, :compress, :compress_threshold, :expires_in, :expire_in, :expired_in, :race_condition_ttl, :coder, :skip_nil]
|
|
|
|
DEFAULT_COMPRESS_LIMIT = 1.kilobyte
|
|
|
|
# Mapping of canonical option names to aliases that a store will recognize.
|
|
OPTION_ALIASES = {
|
|
expires_in: [:expire_in, :expired_in]
|
|
}.freeze
|
|
|
|
module Strategy
|
|
autoload :LocalCache, "active_support/cache/strategy/local_cache"
|
|
end
|
|
|
|
@format_version = 6.1
|
|
|
|
class << self
|
|
attr_accessor :format_version
|
|
|
|
# Creates a new Store object according to the given options.
|
|
#
|
|
# If no arguments are passed to this method, then a new
|
|
# ActiveSupport::Cache::MemoryStore object will be returned.
|
|
#
|
|
# If you pass a Symbol as the first argument, then a corresponding cache
|
|
# store class under the ActiveSupport::Cache namespace will be created.
|
|
# For example:
|
|
#
|
|
# ActiveSupport::Cache.lookup_store(:memory_store)
|
|
# # => returns a new ActiveSupport::Cache::MemoryStore object
|
|
#
|
|
# ActiveSupport::Cache.lookup_store(:mem_cache_store)
|
|
# # => returns a new ActiveSupport::Cache::MemCacheStore object
|
|
#
|
|
# Any additional arguments will be passed to the corresponding cache store
|
|
# class's constructor:
|
|
#
|
|
# ActiveSupport::Cache.lookup_store(:file_store, '/tmp/cache')
|
|
# # => same as: ActiveSupport::Cache::FileStore.new('/tmp/cache')
|
|
#
|
|
# If the first argument is not a Symbol, then it will simply be returned:
|
|
#
|
|
# ActiveSupport::Cache.lookup_store(MyOwnCacheStore.new)
|
|
# # => returns MyOwnCacheStore.new
|
|
def lookup_store(store = nil, *parameters)
|
|
case store
|
|
when Symbol
|
|
options = parameters.extract_options!
|
|
# clean this up once Ruby 2.7 support is dropped
|
|
# see https://github.com/rails/rails/pull/41522#discussion_r581186602
|
|
if options.empty?
|
|
retrieve_store_class(store).new(*parameters)
|
|
else
|
|
retrieve_store_class(store).new(*parameters, **options)
|
|
end
|
|
when Array
|
|
lookup_store(*store)
|
|
when nil
|
|
ActiveSupport::Cache::MemoryStore.new
|
|
else
|
|
store
|
|
end
|
|
end
|
|
|
|
# Expands out the +key+ argument into a key that can be used for the
|
|
# cache store. Optionally accepts a namespace, and all keys will be
|
|
# scoped within that namespace.
|
|
#
|
|
# If the +key+ argument provided is an array, or responds to +to_a+, then
|
|
# each of elements in the array will be turned into parameters/keys and
|
|
# concatenated into a single key. For example:
|
|
#
|
|
# ActiveSupport::Cache.expand_cache_key([:foo, :bar]) # => "foo/bar"
|
|
# ActiveSupport::Cache.expand_cache_key([:foo, :bar], "namespace") # => "namespace/foo/bar"
|
|
#
|
|
# The +key+ argument can also respond to +cache_key+ or +to_param+.
|
|
def expand_cache_key(key, namespace = nil)
|
|
expanded_cache_key = namespace ? +"#{namespace}/" : +""
|
|
|
|
if prefix = ENV["RAILS_CACHE_ID"] || ENV["RAILS_APP_VERSION"]
|
|
expanded_cache_key << "#{prefix}/"
|
|
end
|
|
|
|
expanded_cache_key << retrieve_cache_key(key)
|
|
expanded_cache_key
|
|
end
|
|
|
|
private
|
|
def retrieve_cache_key(key)
|
|
case
|
|
when key.respond_to?(:cache_key_with_version) then key.cache_key_with_version
|
|
when key.respond_to?(:cache_key) then key.cache_key
|
|
when key.is_a?(Array) then key.map { |element| retrieve_cache_key(element) }.to_param
|
|
when key.respond_to?(:to_a) then retrieve_cache_key(key.to_a)
|
|
else key.to_param
|
|
end.to_s
|
|
end
|
|
|
|
# Obtains the specified cache store class, given the name of the +store+.
|
|
# Raises an error when the store class cannot be found.
|
|
def retrieve_store_class(store)
|
|
# require_relative cannot be used here because the class might be
|
|
# provided by another gem, like redis-activesupport for example.
|
|
require "active_support/cache/#{store}"
|
|
rescue LoadError => e
|
|
raise "Could not find cache store adapter for #{store} (#{e})"
|
|
else
|
|
ActiveSupport::Cache.const_get(store.to_s.camelize)
|
|
end
|
|
end
|
|
|
|
# An abstract cache store class. There are multiple cache store
|
|
# implementations, each having its own additional features. See the classes
|
|
# under the ActiveSupport::Cache module, e.g.
|
|
# ActiveSupport::Cache::MemCacheStore. MemCacheStore is currently the most
|
|
# popular cache store for large production websites.
|
|
#
|
|
# 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 and has a +cache_key+ method defined, this
|
|
# method will be called to define the key. Otherwise, the +to_param+
|
|
# method will be called. Hashes and Arrays can also be used as keys. The
|
|
# elements will be delimited by slashes, and the elements within a Hash
|
|
# 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 = -> { @last_mod_time } # Set the namespace to a variable
|
|
# @last_mod_time = Time.now # Invalidate the entire cache by changing namespace
|
|
#
|
|
# Cached data larger than 1kB are compressed by default. To turn off
|
|
# compression, pass <tt>compress: false</tt> to the initializer or to
|
|
# individual +fetch+ or +write+ method calls. The 1kB compression
|
|
# threshold is configurable with the <tt>:compress_threshold</tt> option,
|
|
# specified in bytes.
|
|
class Store
|
|
cattr_accessor :logger, instance_writer: true
|
|
|
|
attr_reader :silence, :options
|
|
alias :silence? :silence
|
|
|
|
class << self
|
|
private
|
|
def retrieve_pool_options(options)
|
|
{}.tap do |pool_options|
|
|
pool_options[:size] = options.delete(:pool_size) if options[:pool_size]
|
|
pool_options[:timeout] = options.delete(:pool_timeout) if options[:pool_timeout]
|
|
end
|
|
end
|
|
|
|
def ensure_connection_pool_added!
|
|
require "connection_pool"
|
|
rescue LoadError => e
|
|
$stderr.puts "You don't have connection_pool installed in your application. Please add it to your Gemfile and run bundle install"
|
|
raise e
|
|
end
|
|
end
|
|
|
|
# Creates a new cache. The options will be passed to any write method calls
|
|
# except for <tt>:namespace</tt> which can be used to set the global
|
|
# namespace for the cache.
|
|
def initialize(options = nil)
|
|
@options = options ? normalize_options(options) : {}
|
|
@options[:compress] = true unless @options.key?(:compress)
|
|
@options[:compress_threshold] = DEFAULT_COMPRESS_LIMIT unless @options.key?(:compress_threshold)
|
|
|
|
@coder = @options.delete(:coder) { default_coder } || NullCoder
|
|
@coder_supports_compression = @coder.respond_to?(:dump_compressed)
|
|
end
|
|
|
|
# Silences the logger.
|
|
def silence!
|
|
@silence = true
|
|
self
|
|
end
|
|
|
|
# Silences the logger within a block.
|
|
def mute
|
|
previous_silence, @silence = defined?(@silence) && @silence, true
|
|
yield
|
|
ensure
|
|
@silence = previous_silence
|
|
end
|
|
|
|
# Fetches data from the cache, using the given key. If there is data in
|
|
# the cache with the given key, then that data is returned.
|
|
#
|
|
# If there is no such data in the cache (a cache miss), then +nil+ will be
|
|
# returned. However, if a block has been passed, that block will be passed
|
|
# the key and executed in the event of a cache miss. The return value of the
|
|
# block will be written to the cache under the given cache key, and that
|
|
# return value will be returned.
|
|
#
|
|
# cache.write('today', 'Monday')
|
|
# cache.fetch('today') # => "Monday"
|
|
#
|
|
# cache.fetch('city') # => nil
|
|
# cache.fetch('city') do
|
|
# 'Duckburgh'
|
|
# end
|
|
# cache.fetch('city') # => "Duckburgh"
|
|
#
|
|
# You may also specify additional options via the +options+ argument.
|
|
# Setting <tt>force: true</tt> forces a cache "miss," meaning we treat
|
|
# the cache value as missing even if it's present. Passing a block is
|
|
# required when +force+ is true so this always results in a cache write.
|
|
#
|
|
# cache.write('today', 'Monday')
|
|
# cache.fetch('today', force: true) { 'Tuesday' } # => 'Tuesday'
|
|
# cache.fetch('today', force: true) # => ArgumentError
|
|
#
|
|
# The +:force+ option is useful when you're calling some other method to
|
|
# ask whether you should force a cache write. Otherwise, it's clearer to
|
|
# just call <tt>Cache#write</tt>.
|
|
#
|
|
# Setting <tt>skip_nil: true</tt> will not cache nil result:
|
|
#
|
|
# cache.fetch('foo') { nil }
|
|
# cache.fetch('bar', skip_nil: true) { nil }
|
|
# cache.exist?('foo') # => true
|
|
# cache.exist?('bar') # => false
|
|
#
|
|
#
|
|
# Setting <tt>compress: false</tt> disables compression of the cache entry.
|
|
#
|
|
# Setting <tt>:expires_in</tt> will set an expiration time on the cache.
|
|
# All caches support auto-expiring content after a specified number of
|
|
# seconds. This value can be specified as an option to the constructor
|
|
# (in which case all entries will be affected), or it can be supplied to
|
|
# the +fetch+ or +write+ method to affect just one entry.
|
|
# <tt>:expire_in</tt> and <tt>:expired_in</tt> are aliases for
|
|
# <tt>:expires_in</tt>.
|
|
#
|
|
# cache = ActiveSupport::Cache::MemoryStore.new(expires_in: 5.minutes)
|
|
# cache.write(key, value, expires_in: 1.minute) # Set a lower value for one entry
|
|
#
|
|
# Setting <tt>:expires_at</tt> will set an absolute expiration time on the cache.
|
|
# All caches support auto-expiring content after a specified number of
|
|
# seconds. This value can only be supplied to the +fetch+ or +write+ method to
|
|
# affect just one entry.
|
|
#
|
|
# cache = ActiveSupport::Cache::MemoryStore.new
|
|
# cache.write(key, value, expires_at: Time.now.at_end_of_hour)
|
|
#
|
|
# Setting <tt>:version</tt> verifies the cache stored under <tt>name</tt>
|
|
# is of the same version. nil is returned on mismatches despite contents.
|
|
# This feature is used to support recyclable cache keys.
|
|
#
|
|
# Setting <tt>:race_condition_ttl</tt> is very useful in situations where
|
|
# a cache entry is used very frequently and is under heavy load. If a
|
|
# cache expires and due to heavy load several different processes will try
|
|
# to read data natively and then they all will try to write to cache. To
|
|
# avoid that case the first process to find an expired cache entry will
|
|
# bump the cache expiration time by the value set in <tt>:race_condition_ttl</tt>.
|
|
# Yes, this process is extending the time for a stale value by another few
|
|
# seconds. Because of extended life of the previous cache, other processes
|
|
# will continue to use slightly stale data for a just a bit longer. In the
|
|
# meantime that first process will go ahead and will write into cache the
|
|
# new value. After that all the processes will start getting the new value.
|
|
# The key is to keep <tt>:race_condition_ttl</tt> small.
|
|
#
|
|
# If the process regenerating the entry errors out, the entry will be
|
|
# regenerated after the specified number of seconds. Also note that the
|
|
# life of stale cache is extended only if it expired recently. Otherwise
|
|
# a new value is generated and <tt>:race_condition_ttl</tt> does not play
|
|
# any role.
|
|
#
|
|
# # Set all values to expire after one minute.
|
|
# cache = ActiveSupport::Cache::MemoryStore.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.seconds) do
|
|
# sleep 1
|
|
# 'new value 1'
|
|
# end
|
|
# end
|
|
#
|
|
# Thread.new do
|
|
# val_2 = cache.fetch('foo', race_condition_ttl: 10.seconds) do
|
|
# 'new value 2'
|
|
# end
|
|
# end
|
|
#
|
|
# cache.fetch('foo') # => "original value"
|
|
# sleep 10 # First thread extended the life of cache by another 10 seconds
|
|
# cache.fetch('foo') # => "new value 1"
|
|
# val_1 # => "new value 1"
|
|
# val_2 # => "original value"
|
|
#
|
|
# Other options will be handled by the specific cache store implementation.
|
|
# 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 +: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, raw: true) do
|
|
# :bar
|
|
# end
|
|
# cache.fetch('foo') # => "bar"
|
|
def fetch(name, options = nil, &block)
|
|
if block_given?
|
|
options = merged_options(options)
|
|
key = normalize_key(name, options)
|
|
|
|
entry = nil
|
|
instrument(:read, name, options) do |payload|
|
|
cached_entry = read_entry(key, **options, event: payload) unless options[:force]
|
|
entry = handle_expired_entry(cached_entry, key, options)
|
|
entry = nil if entry && entry.mismatched?(normalize_version(name, options))
|
|
payload[:super_operation] = :fetch if payload
|
|
payload[:hit] = !!entry if payload
|
|
end
|
|
|
|
if entry
|
|
get_entry_value(entry, name, options)
|
|
else
|
|
save_block_result_to_cache(name, options, &block)
|
|
end
|
|
elsif options && options[:force]
|
|
raise ArgumentError, "Missing block: Calling `Cache#fetch` with `force: true` requires a block."
|
|
else
|
|
read(name, options)
|
|
end
|
|
end
|
|
|
|
# Reads data from the cache, using the given key. If there is data in
|
|
# the cache with the given key, then that data is returned. Otherwise,
|
|
# +nil+ is returned.
|
|
#
|
|
# Note, if data was written with the <tt>:expires_in</tt> or
|
|
# <tt>:version</tt> options, both of these conditions are applied before
|
|
# the data is returned.
|
|
#
|
|
# Options are passed to the underlying cache implementation.
|
|
def read(name, options = nil)
|
|
options = merged_options(options)
|
|
key = normalize_key(name, options)
|
|
version = normalize_version(name, options)
|
|
|
|
instrument(:read, name, options) do |payload|
|
|
entry = read_entry(key, **options, event: payload)
|
|
|
|
if entry
|
|
if entry.expired?
|
|
delete_entry(key, **options)
|
|
payload[:hit] = false if payload
|
|
nil
|
|
elsif entry.mismatched?(version)
|
|
payload[:hit] = false if payload
|
|
nil
|
|
else
|
|
payload[:hit] = true if payload
|
|
entry.value
|
|
end
|
|
else
|
|
payload[:hit] = false if payload
|
|
nil
|
|
end
|
|
end
|
|
end
|
|
|
|
# Reads multiple values at once from the cache. Options can be passed
|
|
# in the last argument.
|
|
#
|
|
# 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)
|
|
|
|
instrument :read_multi, names, options do |payload|
|
|
read_multi_entries(names, **options, event: payload).tap do |results|
|
|
payload[:hits] = results.keys
|
|
end
|
|
end
|
|
end
|
|
|
|
# Cache Storage API to write multiple values at once.
|
|
def write_multi(hash, options = nil)
|
|
options = merged_options(options)
|
|
|
|
instrument :write_multi, hash, options do |payload|
|
|
entries = hash.each_with_object({}) do |(name, value), memo|
|
|
memo[normalize_key(name, options)] = Entry.new(value, **options.merge(version: normalize_version(name, options)))
|
|
end
|
|
|
|
write_multi_entries entries, **options
|
|
end
|
|
end
|
|
|
|
# Fetches data from the cache, using the given keys. If there is data in
|
|
# the cache with the given keys, then that data is returned. Otherwise,
|
|
# the supplied block is called for each key for which there was no data,
|
|
# and the result will be written to the cache and returned.
|
|
# Therefore, you need to pass a block that returns the data to be written
|
|
# to the cache. If you do not want to write the cache when the cache is
|
|
# not found, use #read_multi.
|
|
#
|
|
# Returns a hash with the data for each of the names. For example:
|
|
#
|
|
# cache.write("bim", "bam")
|
|
# cache.fetch_multi("bim", "unknown_key") do |key|
|
|
# "Fallback value for key: #{key}"
|
|
# end
|
|
# # => { "bim" => "bam",
|
|
# # "unknown_key" => "Fallback value for key: unknown_key" }
|
|
#
|
|
# Options are passed to the underlying cache implementation. For example:
|
|
#
|
|
# cache.fetch_multi("fizz", expires_in: 5.seconds) do |key|
|
|
# "buzz"
|
|
# end
|
|
# # => {"fizz"=>"buzz"}
|
|
# cache.read("fizz")
|
|
# # => "buzz"
|
|
# sleep(6)
|
|
# cache.read("fizz")
|
|
# # => nil
|
|
def fetch_multi(*names)
|
|
raise ArgumentError, "Missing block: `Cache#fetch_multi` requires a block." unless block_given?
|
|
|
|
options = names.extract_options!
|
|
options = merged_options(options)
|
|
|
|
instrument :read_multi, names, options do |payload|
|
|
reads = read_multi_entries(names, **options)
|
|
writes = {}
|
|
ordered = names.index_with do |name|
|
|
reads.fetch(name) { writes[name] = yield(name) }
|
|
end
|
|
|
|
payload[:hits] = reads.keys
|
|
payload[:super_operation] = :fetch_multi
|
|
|
|
write_multi(writes, options)
|
|
|
|
ordered
|
|
end
|
|
end
|
|
|
|
# Writes the value to the cache, with the key.
|
|
#
|
|
# Options are passed to the underlying cache implementation.
|
|
def write(name, value, options = nil)
|
|
options = merged_options(options)
|
|
|
|
instrument(:write, name, options) do
|
|
entry = Entry.new(value, **options.merge(version: normalize_version(name, options)))
|
|
write_entry(normalize_key(name, options), entry, **options)
|
|
end
|
|
end
|
|
|
|
# Deletes an entry in the cache. Returns +true+ if an entry is deleted.
|
|
#
|
|
# Options are passed to the underlying cache implementation.
|
|
def delete(name, options = nil)
|
|
options = merged_options(options)
|
|
|
|
instrument(:delete, name) do
|
|
delete_entry(normalize_key(name, options), **options)
|
|
end
|
|
end
|
|
|
|
# Deletes multiple entries in the cache.
|
|
#
|
|
# Options are passed to the underlying cache implementation.
|
|
def delete_multi(names, options = nil)
|
|
options = merged_options(options)
|
|
names.map! { |key| normalize_key(key, options) }
|
|
|
|
instrument :delete_multi, names do
|
|
delete_multi_entries(names, **options)
|
|
end
|
|
end
|
|
|
|
# Returns +true+ if the cache contains an entry for the given key.
|
|
#
|
|
# Options are passed to the underlying cache implementation.
|
|
def exist?(name, options = nil)
|
|
options = merged_options(options)
|
|
|
|
instrument(:exist?, name) do |payload|
|
|
entry = read_entry(normalize_key(name, options), **options, event: payload)
|
|
(entry && !entry.expired? && !entry.mismatched?(normalize_version(name, options))) || false
|
|
end
|
|
end
|
|
|
|
def new_entry(value, options = nil) # :nodoc:
|
|
Entry.new(value, **merged_options(options))
|
|
end
|
|
|
|
# Deletes all entries with keys matching the pattern.
|
|
#
|
|
# Options are passed to the underlying cache implementation.
|
|
#
|
|
# Some implementations may not support this method.
|
|
def delete_matched(matcher, options = nil)
|
|
raise NotImplementedError.new("#{self.class.name} does not support delete_matched")
|
|
end
|
|
|
|
# Increments an integer value in the cache.
|
|
#
|
|
# Options are passed to the underlying cache implementation.
|
|
#
|
|
# Some implementations may not support this method.
|
|
def increment(name, amount = 1, options = nil)
|
|
raise NotImplementedError.new("#{self.class.name} does not support increment")
|
|
end
|
|
|
|
# Decrements an integer value in the cache.
|
|
#
|
|
# Options are passed to the underlying cache implementation.
|
|
#
|
|
# Some implementations may not support this method.
|
|
def decrement(name, amount = 1, options = nil)
|
|
raise NotImplementedError.new("#{self.class.name} does not support decrement")
|
|
end
|
|
|
|
# Cleanups the cache by removing expired entries.
|
|
#
|
|
# Options are passed to the underlying cache implementation.
|
|
#
|
|
# Some implementations may not support this method.
|
|
def cleanup(options = nil)
|
|
raise NotImplementedError.new("#{self.class.name} does not support cleanup")
|
|
end
|
|
|
|
# Clears the entire cache. Be careful with this method since it could
|
|
# affect other processes if shared cache is being used.
|
|
#
|
|
# The options hash is passed to the underlying cache implementation.
|
|
#
|
|
# Some implementations may not support this method.
|
|
def clear(options = nil)
|
|
raise NotImplementedError.new("#{self.class.name} does not support clear")
|
|
end
|
|
|
|
private
|
|
def default_coder
|
|
Coders[Cache.format_version]
|
|
end
|
|
|
|
# Adds 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) # :doc:
|
|
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
|
|
|
|
# Reads an entry from the cache implementation. Subclasses must implement
|
|
# this method.
|
|
def read_entry(key, **options)
|
|
raise NotImplementedError.new
|
|
end
|
|
|
|
# Writes an entry to the cache implementation. Subclasses must implement
|
|
# this method.
|
|
def write_entry(key, entry, **options)
|
|
raise NotImplementedError.new
|
|
end
|
|
|
|
def serialize_entry(entry, **options)
|
|
options = merged_options(options)
|
|
if @coder_supports_compression && options[:compress]
|
|
@coder.dump_compressed(entry, options[:compress_threshold] || DEFAULT_COMPRESS_LIMIT)
|
|
else
|
|
@coder.dump(entry)
|
|
end
|
|
end
|
|
|
|
def deserialize_entry(payload)
|
|
payload.nil? ? nil : @coder.load(payload)
|
|
end
|
|
|
|
# Reads multiple entries from the cache implementation. Subclasses MAY
|
|
# implement this method.
|
|
def read_multi_entries(names, **options)
|
|
names.each_with_object({}) do |name, results|
|
|
key = normalize_key(name, options)
|
|
entry = read_entry(key, **options)
|
|
|
|
next unless entry
|
|
|
|
version = normalize_version(name, options)
|
|
|
|
if entry.expired?
|
|
delete_entry(key, **options)
|
|
elsif !entry.mismatched?(version)
|
|
results[name] = entry.value
|
|
end
|
|
end
|
|
end
|
|
|
|
# Writes multiple entries to the cache implementation. Subclasses MAY
|
|
# implement this method.
|
|
def write_multi_entries(hash, **options)
|
|
hash.each do |key, entry|
|
|
write_entry key, entry, **options
|
|
end
|
|
end
|
|
|
|
# Deletes an entry from the cache implementation. Subclasses must
|
|
# implement this method.
|
|
def delete_entry(key, **options)
|
|
raise NotImplementedError.new
|
|
end
|
|
|
|
# Deletes multiples entries in the cache implementation. Subclasses MAY
|
|
# implement this method.
|
|
def delete_multi_entries(entries, **options)
|
|
entries.count { |key| delete_entry(key, **options) }
|
|
end
|
|
|
|
# Merges the default options with ones specific to a method call.
|
|
def merged_options(call_options)
|
|
if call_options
|
|
call_options = normalize_options(call_options)
|
|
if options.empty?
|
|
call_options
|
|
else
|
|
options.merge(call_options)
|
|
end
|
|
else
|
|
options
|
|
end
|
|
end
|
|
|
|
# Normalize aliased options to their canonical form
|
|
def normalize_options(options)
|
|
options = options.dup
|
|
OPTION_ALIASES.each do |canonical_name, aliases|
|
|
alias_key = aliases.detect { |key| options.key?(key) }
|
|
options[canonical_name] ||= options[alias_key] if alias_key
|
|
options.except!(*aliases)
|
|
end
|
|
|
|
options
|
|
end
|
|
|
|
# Expands and namespaces the cache key. May be overridden by
|
|
# cache stores to do additional normalization.
|
|
def normalize_key(key, options = nil)
|
|
namespace_key expanded_key(key), options
|
|
end
|
|
|
|
# Prefix the key with a namespace string:
|
|
#
|
|
# namespace_key 'foo', namespace: 'cache'
|
|
# # => 'cache:foo'
|
|
#
|
|
# With a namespace block:
|
|
#
|
|
# namespace_key 'foo', namespace: -> { 'cache' }
|
|
# # => 'cache:foo'
|
|
def namespace_key(key, options = nil)
|
|
options = merged_options(options)
|
|
namespace = options[:namespace]
|
|
|
|
if namespace.respond_to?(:call)
|
|
namespace = namespace.call
|
|
end
|
|
|
|
if key && key.encoding != Encoding::UTF_8
|
|
key = key.dup.force_encoding(Encoding::UTF_8)
|
|
end
|
|
|
|
if namespace
|
|
"#{namespace}:#{key}"
|
|
else
|
|
key
|
|
end
|
|
end
|
|
|
|
# Expands key to be a consistent string value. Invokes +cache_key+ if
|
|
# object responds to +cache_key+. Otherwise, +to_param+ method will be
|
|
# called. If the key is a Hash, then keys will be sorted alphabetically.
|
|
def expanded_key(key)
|
|
return key.cache_key.to_s if key.respond_to?(:cache_key)
|
|
|
|
case key
|
|
when Array
|
|
if key.size > 1
|
|
key.collect { |element| expanded_key(element) }
|
|
else
|
|
expanded_key(key.first)
|
|
end
|
|
when Hash
|
|
key.collect { |k, v| "#{k}=#{v}" }.sort!
|
|
else
|
|
key
|
|
end.to_param
|
|
end
|
|
|
|
def normalize_version(key, options = nil)
|
|
(options && options[:version].try(:to_param)) || expanded_version(key)
|
|
end
|
|
|
|
def expanded_version(key)
|
|
case
|
|
when key.respond_to?(:cache_version) then key.cache_version.to_param
|
|
when key.is_a?(Array) then key.map { |element| expanded_version(element) }.tap(&:compact!).to_param
|
|
when key.respond_to?(:to_a) then expanded_version(key.to_a)
|
|
end
|
|
end
|
|
|
|
def instrument(operation, key, options = nil)
|
|
if logger && logger.debug? && !silence?
|
|
logger.debug "Cache #{operation}: #{normalize_key(key, options)}#{options.blank? ? "" : " (#{options.inspect})"}"
|
|
end
|
|
|
|
payload = { key: key, store: self.class.name }
|
|
payload.merge!(options) if options.is_a?(Hash)
|
|
ActiveSupport::Notifications.instrument("cache_#{operation}.active_support", payload) { yield(payload) }
|
|
end
|
|
|
|
def handle_expired_entry(entry, key, options)
|
|
if entry && entry.expired?
|
|
race_ttl = options[:race_condition_ttl].to_i
|
|
if (race_ttl > 0) && (Time.now.to_f - entry.expires_at <= race_ttl)
|
|
# When an entry has a positive :race_condition_ttl defined, put the stale entry back into the cache
|
|
# for a brief period while the entry is being recalculated.
|
|
entry.expires_at = Time.now.to_f + race_ttl
|
|
write_entry(key, entry, expires_in: race_ttl * 2)
|
|
else
|
|
delete_entry(key, **options)
|
|
end
|
|
entry = nil
|
|
end
|
|
entry
|
|
end
|
|
|
|
def get_entry_value(entry, name, options)
|
|
instrument(:fetch_hit, name, options) { }
|
|
entry.value
|
|
end
|
|
|
|
def save_block_result_to_cache(name, options)
|
|
result = instrument(:generate, name, options) do
|
|
yield(name)
|
|
end
|
|
|
|
write(name, result, options) unless result.nil? && options[:skip_nil]
|
|
result
|
|
end
|
|
end
|
|
|
|
module NullCoder # :nodoc:
|
|
extend self
|
|
|
|
def dump(entry)
|
|
entry
|
|
end
|
|
|
|
def dump_compressed(entry, threshold)
|
|
entry.compressed(threshold)
|
|
end
|
|
|
|
def load(payload)
|
|
payload
|
|
end
|
|
end
|
|
|
|
module Coders # :nodoc:
|
|
MARK_61 = "\x04\b".b.freeze # The one set by Marshal.
|
|
MARK_70_UNCOMPRESSED = "\x00".b.freeze
|
|
MARK_70_COMPRESSED = "\x01".b.freeze
|
|
|
|
class << self
|
|
def [](version)
|
|
case version
|
|
when 6.1
|
|
Rails61Coder
|
|
when 7.0
|
|
Rails70Coder
|
|
else
|
|
raise ArgumentError, "Unknown ActiveSupport::Cache.format_version #{Cache.format_version.inspect}"
|
|
end
|
|
end
|
|
end
|
|
|
|
module Loader
|
|
extend self
|
|
|
|
def load(payload)
|
|
if !payload.is_a?(String)
|
|
ActiveSupport::Cache::Store.logger&.warn %{Payload wasn't a string, was #{payload.class.name} - couldn't unmarshal, so returning nil."}
|
|
|
|
return nil
|
|
elsif payload.start_with?(MARK_70_UNCOMPRESSED)
|
|
members = Marshal.load(payload.byteslice(1..-1))
|
|
elsif payload.start_with?(MARK_70_COMPRESSED)
|
|
members = Marshal.load(Zlib::Inflate.inflate(payload.byteslice(1..-1)))
|
|
elsif payload.start_with?(MARK_61)
|
|
return Marshal.load(payload)
|
|
else
|
|
ActiveSupport::Cache::Store.logger&.warn %{Invalid cache prefix: #{payload.byteslice(0).inspect}, expected "\\x00" or "\\x01"}
|
|
|
|
return nil
|
|
end
|
|
Entry.unpack(members)
|
|
end
|
|
end
|
|
|
|
module Rails61Coder
|
|
include Loader
|
|
extend self
|
|
|
|
def dump(entry)
|
|
Marshal.dump(entry)
|
|
end
|
|
|
|
def dump_compressed(entry, threshold)
|
|
Marshal.dump(entry.compressed(threshold))
|
|
end
|
|
end
|
|
|
|
module Rails70Coder
|
|
include Loader
|
|
extend self
|
|
|
|
def dump(entry)
|
|
MARK_70_UNCOMPRESSED + Marshal.dump(entry.pack)
|
|
end
|
|
|
|
def dump_compressed(entry, threshold)
|
|
payload = Marshal.dump(entry.pack)
|
|
if payload.bytesize >= threshold
|
|
compressed_payload = Zlib::Deflate.deflate(payload)
|
|
if compressed_payload.bytesize < payload.bytesize
|
|
return MARK_70_COMPRESSED + compressed_payload
|
|
end
|
|
end
|
|
|
|
MARK_70_UNCOMPRESSED + payload
|
|
end
|
|
end
|
|
end
|
|
|
|
# This class is used to represent cache entries. Cache entries have a value, an optional
|
|
# expiration time, and an optional version. The expiration time is used to support the :race_condition_ttl option
|
|
# on the cache. The version is used to support the :version option on the cache for rejecting
|
|
# mismatches.
|
|
#
|
|
# 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:
|
|
class << self
|
|
def unpack(members)
|
|
new(members[0], expires_at: members[1], version: members[2])
|
|
end
|
|
end
|
|
|
|
attr_reader :version
|
|
|
|
# Creates a new cache entry for the specified value. Options supported are
|
|
# +:compressed+, +:version+, +:expires_at+ and +:expires_in+.
|
|
def initialize(value, compressed: false, version: nil, expires_in: nil, expires_at: nil, **)
|
|
@value = value
|
|
@version = version
|
|
@created_at = 0.0
|
|
@expires_in = expires_at&.to_f || expires_in && (expires_in.to_f + Time.now.to_f)
|
|
@compressed = true if compressed
|
|
end
|
|
|
|
def value
|
|
compressed? ? uncompress(@value) : @value
|
|
end
|
|
|
|
def mismatched?(version)
|
|
@version && version && @version != version
|
|
end
|
|
|
|
# Checks 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
|
|
|
|
def expires_at
|
|
@expires_in ? @created_at + @expires_in : nil
|
|
end
|
|
|
|
def expires_at=(value)
|
|
if value
|
|
@expires_in = value.to_f - @created_at
|
|
else
|
|
@expires_in = nil
|
|
end
|
|
end
|
|
|
|
# Returns the size of the cached value. This could be less than
|
|
# <tt>value.bytesize</tt> if the data is compressed.
|
|
def bytesize
|
|
case value
|
|
when NilClass
|
|
0
|
|
when String
|
|
@value.bytesize
|
|
else
|
|
@s ||= Marshal.dump(@value).bytesize
|
|
end
|
|
end
|
|
|
|
def compressed? # :nodoc:
|
|
defined?(@compressed)
|
|
end
|
|
|
|
def compressed(compress_threshold)
|
|
return self if compressed?
|
|
|
|
case @value
|
|
when nil, true, false, Numeric
|
|
uncompressed_size = 0
|
|
when String
|
|
uncompressed_size = @value.bytesize
|
|
else
|
|
serialized = Marshal.dump(@value)
|
|
uncompressed_size = serialized.bytesize
|
|
end
|
|
|
|
if uncompressed_size >= compress_threshold
|
|
serialized ||= Marshal.dump(@value)
|
|
compressed = Zlib::Deflate.deflate(serialized)
|
|
|
|
if compressed.bytesize < uncompressed_size
|
|
return Entry.new(compressed, compressed: true, expires_at: expires_at, version: version)
|
|
end
|
|
end
|
|
self
|
|
end
|
|
|
|
def local?
|
|
false
|
|
end
|
|
|
|
# Duplicates 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!
|
|
if @value && !compressed? && !(@value.is_a?(Numeric) || @value == true || @value == false)
|
|
if @value.is_a?(String)
|
|
@value = @value.dup
|
|
else
|
|
@value = Marshal.load(Marshal.dump(@value))
|
|
end
|
|
end
|
|
end
|
|
|
|
def pack
|
|
members = [value, expires_at, version]
|
|
members.pop while !members.empty? && members.last.nil?
|
|
members
|
|
end
|
|
|
|
private
|
|
def uncompress(value)
|
|
Marshal.load(Zlib::Inflate.inflate(value))
|
|
end
|
|
end
|
|
end
|
|
end
|