# frozen_string_literal: true
require "zlib"
require "active_support/core_ext/array/extract_options"
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/object/to_param"
require "active_support/core_ext/object/try"
require "active_support/core_ext/string/inflections"
require_relative "cache/coder"
require_relative "cache/entry"
require_relative "cache/serializer_with_fallback"
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 = [
:coder,
:compress,
:compress_threshold,
:compressor,
:expire_in,
:expired_in,
:expires_in,
:namespace,
:race_condition_ttl,
:serializer,
:skip_nil,
]
# Mapping of canonical option names to aliases that a store will recognize.
OPTION_ALIASES = {
expires_in: [:expire_in, :expired_in]
}.freeze
DEFAULT_COMPRESS_LIMIT = 1.kilobyte
# Raised by coders when the cache entry can't be deserialized.
# This error is treated as a cache miss.
DeserializationError = Class.new(StandardError)
module Strategy
autoload :LocalCache, "active_support/cache/strategy/local_cache"
end
@format_version = 7.0
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!
retrieve_store_class(store).new(*parameters, **options)
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
# = Active Support \Cache \Store
#
# 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 Ruby object that is supported
# by its +coder+'s +dump+ and +load+ methods.
#
# cache = ActiveSupport::Cache::MemoryStore.new
#
# cache.read('city') # => nil
# cache.write('city', "Duckburgh") # => true
# cache.read('city') # => "Duckburgh"
#
# cache.write('not serializable', Proc.new {}) # => TypeError
#
# 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
#
class Store
cattr_accessor :logger, instance_writer: true
cattr_accessor :raise_on_invalid_cache_expiration_time, default: false
attr_reader :silence, :options
alias :silence? :silence
class << self
private
DEFAULT_POOL_OPTIONS = { size: 5, timeout: 5 }.freeze
private_constant :DEFAULT_POOL_OPTIONS
def retrieve_pool_options(options)
if options.key?(:pool)
pool_options = options.delete(:pool)
else
pool_options = true
end
case pool_options
when false, nil
return false
when true
pool_options = DEFAULT_POOL_OPTIONS
when Hash
pool_options[:size] = Integer(pool_options[:size]) if pool_options.key?(:size)
pool_options[:timeout] = Float(pool_options[:timeout]) if pool_options.key?(:timeout)
pool_options = DEFAULT_POOL_OPTIONS.merge(pool_options)
else
raise TypeError, "Invalid :pool argument, expected Hash, got: #{pool_options.inspect}"
end
pool_options unless pool_options.empty?
end
end
# Creates a new cache.
#
# ==== Options
#
# [+:namespace+]
# Sets the namespace for the cache. This option is especially useful if
# your application shares a cache with other applications.
#
# [+:serializer+]
# The serializer for cached values. Must respond to +dump+ and +load+.
#
# The default serializer depends on the cache format version (set via
# +config.active_support.cache_format_version+ when using Rails). The
# default serializer for each format version includes a fallback
# mechanism to deserialize values from any format version. This behavior
# makes it easy to migrate between format versions without invalidating
# the entire cache.
#
# You can also specify serializer: :message_pack to use a
# preconfigured serializer based on ActiveSupport::MessagePack. The
# +:message_pack+ serializer includes the same deserialization fallback
# mechanism, allowing easy migration from (or to) the default
# serializer. The +:message_pack+ serializer may improve performance,
# but it requires the +msgpack+ gem.
#
# [+:compressor+]
# The compressor for serialized cache values. Must respond to +deflate+
# and +inflate+.
#
# The default compressor is +Zlib+. To define a new custom compressor
# that also decompresses old cache entries, you can check compressed
# values for Zlib's "\x78" signature:
#
# module MyCompressor
# def self.deflate(dumped)
# # compression logic... (make sure result does not start with "\x78"!)
# end
#
# def self.inflate(compressed)
# if compressed.start_with?("\x78")
# Zlib.inflate(compressed)
# else
# # decompression logic...
# end
# end
# end
#
# ActiveSupport::Cache.lookup_store(:redis_cache_store, compressor: MyCompressor)
#
# [+:coder+]
# The coder for serializing and (optionally) compressing cache entries.
# Must respond to +dump+ and +load+.
#
# The default coder composes the serializer and compressor, and includes
# some performance optimizations. If you only need to override the
# serializer or compressor, you should specify the +:serializer+ or
# +:compressor+ options instead.
#
# If the store can handle cache entries directly, you may also specify
# coder: nil to omit the serializer, compressor, and coder. For
# example, if you are using ActiveSupport::Cache::MemoryStore and can
# guarantee that cache values will not be mutated, you can specify
# coder: nil to avoid the overhead of safeguarding against
# mutation.
#
# The +:coder+ option is mutally exclusive with the +:serializer+ and
# +:compressor+ options. Specifying them together will raise an
# +ArgumentError+.
#
# Any other specified options are treated as default options for the
# relevant cache operations, such as #read, #write, and #fetch.
def initialize(options = nil)
@options = options ? validate_options(normalize_options(options)) : {}
@options[:compress] = true unless @options.key?(:compress)
@options[:compress_threshold] ||= DEFAULT_COMPRESS_LIMIT
@coder = @options.delete(:coder) do
legacy_serializer = Cache.format_version < 7.1 && !@options[:serializer]
serializer = @options.delete(:serializer) || default_serializer
serializer = Cache::SerializerWithFallback[serializer] if serializer.is_a?(Symbol)
compressor = @options.delete(:compressor) { Zlib }
Cache::Coder.new(serializer, compressor, legacy_serializer: legacy_serializer)
end
@coder ||= Cache::SerializerWithFallback[:passthrough]
@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 = @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"
#
# ==== Options
#
# Internally, +fetch+ calls +read_entry+, and calls +write_entry+ on a
# cache miss. Thus, +fetch+ supports the same options as #read and #write.
# Additionally, +fetch+ supports the following options:
#
# * force: true - 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 +write+.
#
# * skip_nil: true - Prevents caching a nil result:
#
# cache.fetch('foo') { nil }
# cache.fetch('bar', skip_nil: true) { nil }
# cache.exist?('foo') # => true
# cache.exist?('bar') # => false
#
# * +:race_condition_ttl+ - Specifies the number of seconds during which
# an expired value can be reused while a new value is being generated.
# This can be used to prevent race conditions when cache entries expire,
# by preventing multiple processes from simultaneously regenerating the
# same entry (also known as the dog pile effect).
#
# When a process encounters a cache entry that has expired less than
# +:race_condition_ttl+ seconds ago, it will bump the expiration time by
# +:race_condition_ttl+ seconds before generating a new value. During
# this extended time window, while the process generates a new value,
# other processes will continue to use the old value. After the first
# process writes the new value, other processes will then use it.
#
# If the first process errors out while generating a new value, another
# process can try to generate a new value after the extended time window
# has elapsed.
#
# # Set all values to expire after one minute.
# cache = ActiveSupport::Cache::MemoryStore.new(expires_in: 1)
#
# cache.write("foo", "original value")
# val_1 = nil
# val_2 = nil
# p cache.read("foo") # => "original value"
#
# sleep 1 # wait until the cache expires
#
# t1 = Thread.new do
# # fetch does the following:
# # 1. gets an recent expired entry
# # 2. extends the expiry by 2 seconds (race_condition_ttl)
# # 3. regenerates the new value
# val_1 = cache.fetch("foo", race_condition_ttl: 2) do
# sleep 1
# "new value 1"
# end
# end
#
# # Wait until t1 extends the expiry of the entry
# # but before generating the new value
# sleep 0.1
#
# val_2 = cache.fetch("foo", race_condition_ttl: 2) do
# # This block won't be executed because t1 extended the expiry
# "new value 2"
# end
#
# t1.join
#
# p val_1 # => "new value 1"
# p val_2 # => "oritinal value"
# p cache.fetch("foo") # => "new value 1"
#
# # The entry requires 3 seconds to expire (expires_in + race_condition_ttl)
# # We have waited 2 seconds already (sleep(1) + t1.join) thus we need to wait 1
# # more second to see the entry expire.
# sleep 1
#
# p cache.fetch("foo") # => nil
#
# ==== Dynamic Options
#
# In some cases it may be necessary to dynamically compute options based
# on the cached value. To support this, an ActiveSupport::Cache::WriteOptions
# instance is passed as the second argument to the block. For example:
#
# cache.fetch("authentication-token:#{user.id}") do |key, options|
# token = authenticate_to_service
# options.expires_at = token.expires_at
# token
# end
#
def fetch(name, options = nil, &block)
if block_given?
options = merged_options(options)
key = normalize_key(name, options)
entry = nil
unless options[:force]
instrument(:read, key, options) do |payload|
cached_entry = read_entry(key, **options, event: payload)
entry = handle_expired_entry(cached_entry, key, options)
if entry
if entry.mismatched?(normalize_version(name, options))
entry = nil
else
begin
entry.value
rescue DeserializationError
entry = nil
end
end
end
payload[:super_operation] = :fetch if payload
payload[:hit] = !!entry if payload
end
end
if entry
get_entry_value(entry, name, options)
else
save_block_result_to_cache(name, key, 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 :expires_in or
# :version options, both of these conditions are applied before
# the data is returned.
#
# ==== Options
#
# * +:namespace+ - Replace the store namespace for this call.
# * +:version+ - Specifies a version for the cache entry. If the cached
# version does not match the requested version, the read will be treated
# as a cache miss. This feature is used to support recyclable cache keys.
#
# Other options will be handled by the specific cache store implementation.
def read(name, options = nil)
options = merged_options(options)
key = normalize_key(name, options)
version = normalize_version(name, options)
instrument(:read, key, 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
begin
entry.value
rescue DeserializationError
payload[:hit] = false
nil
end
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)
return {} if names.empty?
options = names.extract_options!
options = merged_options(options)
keys = names.map { |name| normalize_key(name, options) }
instrument_multi :read_multi, keys, options do |payload|
read_multi_entries(names, **options, event: payload).tap do |results|
payload[:hits] = results.keys.map { |name| normalize_key(name, options) }
end
end
end
# Cache Storage API to write multiple values at once.
def write_multi(hash, options = nil)
return hash if hash.empty?
options = merged_options(options)
normalized_hash = hash.transform_keys { |key| normalize_key(key, options) }
instrument_multi :write_multi, normalized_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" }
#
# You may also specify additional options via the +options+ argument. See #fetch for details.
# Other 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?
return {} if names.empty?
options = names.extract_options!
options = merged_options(options)
keys = names.map { |name| normalize_key(name, options) }
writes = {}
ordered = instrument_multi :read_multi, keys, options do |payload|
if options[:force]
reads = {}
else
reads = read_multi_entries(names, **options)
end
ordered = names.index_with do |name|
reads.fetch(name) { writes[name] = yield(name) }
end
writes.compact! if options[:skip_nil]
payload[:hits] = reads.keys.map { |name| normalize_key(name, options) }
payload[:super_operation] = :fetch_multi
ordered
end
write_multi(writes, options)
ordered
end
# Writes the value to the cache with the key. The value must be supported
# by the +coder+'s +dump+ and +load+ methods.
#
# Returns +true+ if the write succeeded, +nil+ if there was an error talking
# to the cache backend, or +false+ if the write failed for another reason.
#
# By default, cache entries larger than 1kB are compressed. Compression
# allows more data to be stored in the same memory footprint, leading to
# fewer cache evictions and higher hit rates.
#
# ==== Options
#
# * compress: false - Disables compression of the cache entry.
#
# * +:compress_threshold+ - The compression threshold, specified in bytes.
# \Cache entries larger than this threshold will be compressed. Defaults
# to +1.kilobyte+.
#
# * +:expires_in+ - Sets a relative expiration time for the cache entry,
# specified in seconds. +:expire_in+ and +:expired_in+ are aliases for
# +:expires_in+.
#
# cache = ActiveSupport::Cache::MemoryStore.new(expires_in: 5.minutes)
# cache.write(key, value, expires_in: 1.minute) # Set a lower value for one entry
#
# * +:expires_at+ - Sets an absolute expiration time for the cache entry.
#
# cache = ActiveSupport::Cache::MemoryStore.new
# cache.write(key, value, expires_at: Time.now.at_end_of_hour)
#
# * +:version+ - Specifies a version for the cache entry. When reading
# from the cache, if the cached version does not match the requested
# version, the read will be treated as a cache miss. This feature is
# used to support recyclable cache keys.
#
# Other options will be handled by the specific cache store implementation.
def write(name, value, options = nil)
options = merged_options(options)
key = normalize_key(name, options)
instrument(:write, key, options) do
entry = Entry.new(value, **options.merge(version: normalize_version(name, options)))
write_entry(key, entry, **options)
end
end
# Deletes an entry in the cache. Returns +true+ if an entry is deleted
# and +false+ otherwise.
#
# Options are passed to the underlying cache implementation.
def delete(name, options = nil)
options = merged_options(options)
key = normalize_key(name, options)
instrument(:delete, key, options) do
delete_entry(key, **options)
end
end
# Deletes multiple entries in the cache. Returns the number of deleted
# entries.
#
# Options are passed to the underlying cache implementation.
def delete_multi(names, options = nil)
return 0 if names.empty?
options = merged_options(options)
names.map! { |key| normalize_key(key, options) }
instrument_multi(:delete_multi, names, options) 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)
key = normalize_key(name, options)
instrument(:exist?, key) do |payload|
entry = read_entry(key, **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
# Cleans up 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_serializer
case Cache.format_version
when 7.0
Cache::SerializerWithFallback[:marshal_7_0]
when 7.1
Cache::SerializerWithFallback[:marshal_7_1]
else
raise ArgumentError, "Unrecognized ActiveSupport::Cache.format_version: #{Cache.format_version.inspect}"
end
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])
else
@coder.dump(entry)
end
end
def deserialize_entry(payload, **)
payload.nil? ? nil : @coder.load(payload)
rescue DeserializationError
nil
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 call_options.key?(:expires_in) && call_options.key?(:expires_at)
raise ArgumentError, "Either :expires_in or :expires_at can be supplied, but not both"
end
expires_at = call_options.delete(:expires_at)
call_options[:expires_in] = (expires_at - Time.now) if expires_at
if call_options[:expires_in].is_a?(Time)
expires_in = call_options[:expires_in]
raise ArgumentError.new("expires_in parameter should not be a Time. Did you mean to use expires_at? Got: #{expires_in}")
end
if call_options[:expires_in]&.negative?
expires_in = call_options.delete(:expires_in)
handle_invalid_expires_in("Cache expiration time is invalid, cannot be negative: #{expires_in}")
end
if options.empty?
call_options
else
options.merge(call_options)
end
else
options
end
end
def handle_invalid_expires_in(message)
error = ArgumentError.new(message)
if ActiveSupport::Cache::Store.raise_on_invalid_cache_expiration_time
raise error
else
ActiveSupport.error_reporter&.report(error, handled: true, severity: :warning)
logger.error("#{error.class}: #{error.message}") if logger
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
def validate_options(options)
if options.key?(:coder) && options[:serializer]
raise ArgumentError, "Cannot specify :serializer and :coder options together"
end
if options.key?(:coder) && options[:compressor]
raise ArgumentError, "Cannot specify :compressor and :coder options together"
end
if Cache.format_version < 7.1 && !options[:serializer] && options[:compressor]
raise ArgumentError, "Cannot specify :compressor option when using" \
" default serializer and cache format version is < 7.1"
end
options
end
# Expands and namespaces the cache key.
# Raises an exception when the key is +nil+ or an empty string.
# May be overridden by cache stores to do additional normalization.
def normalize_key(key, options = nil)
str_key = expanded_key(key)
raise(ArgumentError, "key cannot be blank") if !str_key || str_key.empty?
namespace_key str_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, call_options = nil)
namespace = if call_options&.key?(:namespace)
call_options[:namespace]
else
options[:namespace]
end
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, &block)
_instrument(operation, key: key, options: options, &block)
end
def instrument_multi(operation, keys, options = nil, &block)
_instrument(operation, multi: true, key: keys, options: options, &block)
end
def _instrument(operation, multi: false, options: nil, **payload, &block)
if logger && logger.debug? && !silence?
debug_key =
if multi
": #{payload[:key].size} key(s) specified"
elsif payload[:key]
": #{payload[:key]}"
end
debug_options = " (#{options.inspect})" unless options.blank?
logger.debug "Cache #{operation}#{debug_key}#{debug_options}"
end
payload[:store] = self.class.name
payload.merge!(options) if options.is_a?(Hash)
ActiveSupport::Notifications.instrument("cache_#{operation}.active_support", payload) do
block&.call(payload)
end
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
options[:expires_in] = race_ttl * 2
write_entry(key, entry, **options)
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, key, options)
options = options.dup
result = instrument(:generate, key, options) do
yield(name, WriteOptions.new(options))
end
write(name, result, options) unless result.nil? && options[:skip_nil]
result
end
end
# Enables the dynamic configuration of Cache entry options while ensuring
# that conflicting options are not both set. When a block is given to
# ActiveSupport::Cache::Store#fetch, the second argument will be an
# instance of +WriteOptions+.
class WriteOptions
def initialize(options) # :nodoc:
@options = options
end
def version
@options[:version]
end
def version=(version)
@options[:version] = version
end
def expires_in
@options[:expires_in]
end
# Sets the Cache entry's +expires_in+ value. If an +expires_at+ option was
# previously set, this will unset it since +expires_in+ and +expires_at+
# cannot both be set.
def expires_in=(expires_in)
@options.delete(:expires_at)
@options[:expires_in] = expires_in
end
def expires_at
@options[:expires_at]
end
# Sets the Cache entry's +expires_at+ value. If an +expires_in+ option was
# previously set, this will unset it since +expires_at+ and +expires_in+
# cannot both be set.
def expires_at=(expires_at)
@options.delete(:expires_in)
@options[:expires_at] = expires_at
end
end
end
end