1 files changed, 74 insertions, 65 deletions

diff --git a/activesupport/lib/active_support/cache/mem_cache_store.rb b/activesupport/lib/active_support/cache/mem_cache_store.rb
index 2ca4b51efa..cae0d44e7d 100644
--- a/activesupport/lib/active_support/cache/mem_cache_store.rb
+++ b/activesupport/lib/active_support/cache/mem_cache_store.rb
@@ -1,18 +1,19 @@
+# frozen_string_literal: true
+
 begin
-  require 'dalli'
+  require "dalli"
 rescue LoadError => e
   $stderr.puts "You don't have dalli installed in your application. Please add it to your Gemfile and run bundle install"
   raise e
 end
 
-require 'digest/md5'
-require 'active_support/core_ext/marshal'
-require 'active_support/core_ext/array/extract_options'
+require "active_support/core_ext/marshal"
+require "active_support/core_ext/array/extract_options"
 
 module ActiveSupport
   module Cache
     # A cache store implementation which stores data in Memcached:
-    # http://memcached.org/
+    # https://memcached.org
     #
     # This is currently the most popular cache store for production websites.
     #
@@ -26,24 +27,24 @@ module ActiveSupport
     class MemCacheStore < Store
       # Provide support for raw values in the local cache strategy.
       module LocalCacheWithRaw # :nodoc:
-        protected
-        def read_entry(key, options)
-          entry = super
-          if options[:raw] && local_cache && entry
-            entry = deserialize_entry(entry.value)
+        private
+          def read_entry(key, options)
+            entry = super
+            if options[:raw] && local_cache && entry
+              entry = deserialize_entry(entry.value)
+            end
+            entry
           end
-          entry
-        end
 
-        def write_entry(key, entry, options) # :nodoc:
-          if options[:raw] && local_cache
-            raw_entry = Entry.new(entry.value.to_s)
-            raw_entry.expires_at = entry.expires_at
-            super(key, raw_entry, options)
-          else
-            super
+          def write_entry(key, entry, options)
+            if options[:raw] && local_cache
+              raw_entry = Entry.new(entry.value.to_s)
+              raw_entry.expires_at = entry.expires_at
+              super(key, raw_entry, options)
+            else
+              super
+            end
           end
-        end
       end
 
       prepend Strategy::LocalCache
@@ -62,7 +63,23 @@ module ActiveSupport
         addresses = addresses.flatten
         options = addresses.extract_options!
         addresses = ["localhost:11211"] if addresses.empty?
-        Dalli::Client.new(addresses, options)
+
+        pool_options = {}
+        pool_options[:size] = options[:pool_size] if options[:pool_size]
+        pool_options[:timeout] = options[:pool_timeout] if options[:pool_timeout]
+
+        if pool_options.empty?
+          Dalli::Client.new(addresses, options)
+        else
+          begin
+            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
+
+          ConnectionPool.new(pool_options) { Dalli::Client.new(addresses, options.merge(threadsafe: false)) }
+        end
       end
 
       # Creates a new MemCacheStore object, with the given memcached server
@@ -85,36 +102,20 @@ module ActiveSupport
           @data = addresses.first
         else
           mem_cache_options = options.dup
-          UNIVERSAL_OPTIONS.each{|name| mem_cache_options.delete(name)}
+          UNIVERSAL_OPTIONS.each { |name| mem_cache_options.delete(name) }
           @data = self.class.build_mem_cache(*(addresses + [mem_cache_options]))
         end
       end
 
-      # Reads multiple values 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 = Hash[names.map{|name| [normalize_key(name, options), name]}]
-        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
-
       # 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:
+      def increment(name, amount = 1, options = nil)
         options = merged_options(options)
-        instrument(:increment, name, :amount => amount) do
+        instrument(:increment, name, amount: amount) do
           rescue_error_with nil do
-            @data.incr(normalize_key(name, options), amount)
+            @data.with { |c| c.incr(normalize_key(name, options), amount, options[:expires_in]) }
           end
         end
       end
@@ -123,11 +124,11 @@ module ActiveSupport
       # 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:
+      def decrement(name, amount = 1, options = nil)
         options = merged_options(options)
-        instrument(:decrement, name, :amount => amount) do
+        instrument(:decrement, name, amount: amount) do
           rescue_error_with nil do
-            @data.decr(normalize_key(name, options), amount)
+            @data.with { |c| c.decr(normalize_key(name, options), amount, options[:expires_in]) }
           end
         end
       end
@@ -135,22 +136,22 @@ module ActiveSupport
       # Clear the entire cache on all memcached servers. This method should
       # be used with care when shared cache is being used.
       def clear(options = nil)
-        rescue_error_with(nil) { @data.flush_all }
+        rescue_error_with(nil) { @data.with { |c| c.flush_all } }
       end
 
       # Get the statistics from the memcached servers.
       def stats
-        @data.stats
+        @data.with { |c| c.stats }
       end
 
-      protected
+      private
         # Read an entry from the cache.
-        def read_entry(key, options) # :nodoc:
-          rescue_error_with(nil) { deserialize_entry(@data.get(key, options)) }
+        def read_entry(key, options)
+          rescue_error_with(nil) { deserialize_entry(@data.with { |c| c.get(key, options) }) }
         end
 
         # Write an entry to the cache.
-        def write_entry(key, entry, options) # :nodoc:
+        def write_entry(key, entry, options)
           method = options && options[:unless_exist] ? :add : :set
           value = options[:raw] ? entry.value.to_s : entry
           expires_in = options[:expires_in].to_i
@@ -159,16 +160,32 @@ module ActiveSupport
             expires_in += 5.minutes
           end
           rescue_error_with false do
-            @data.send(method, key, value, expires_in, options)
+            @data.with { |c| c.send(method, key, value, expires_in, options) }
           end
         end
 
-        # Delete an entry from the cache.
-        def delete_entry(key, options) # :nodoc:
-          rescue_error_with(false) { @data.delete(key) }
+        # Reads multiple entries from the cache implementation.
+        def read_multi_entries(names, options)
+          keys_to_names = Hash[names.map { |name| [normalize_key(name, options), name] }]
+
+          raw_values = @data.with { |c| c.get_multi(keys_to_names.keys) }
+          values = {}
+
+          raw_values.each do |key, value|
+            entry = deserialize_entry(value)
+
+            unless entry.expired? || entry.mismatched?(normalize_version(keys_to_names[key], options))
+              values[keys_to_names[key]] = entry.value
+            end
+          end
+
+          values
         end
 
-      private
+        # Delete an entry from the cache.
+        def delete_entry(key, options)
+          rescue_error_with(false) { @data.with { |c| c.delete(key) } }
+        end
 
         # Memcache keys are binaries. So we need to force their encoding to binary
         # before applying the regular expression to ensure we are escaping all
@@ -176,16 +193,8 @@ module ActiveSupport
         def normalize_key(key, options)
           key = super.dup
           key = key.force_encoding(Encoding::ASCII_8BIT)
-          key = key.gsub(ESCAPE_KEY_CHARS){ |match| "%#{match.getbyte(0).to_s(16).upcase}" }
-          key = "#{key[0, 213]}:md5:#{Digest::MD5.hexdigest(key)}" if key.size > 250
-          key
-        end
-
-        def escape_key(key)
-          ActiveSupport::Deprecation.warn(<<-MESSAGE.strip_heredoc)
-            `escape_key` is deprecated and will be removed from Rails 5.1.
-            Please use `normalize_key` which will return a fully resolved key or nothing.
-          MESSAGE
+          key = key.gsub(ESCAPE_KEY_CHARS) { |match| "%#{match.getbyte(0).to_s(16).upcase}" }
+          key = "#{key[0, 213]}:md5:#{ActiveSupport::Digest.hexdigest(key)}" if key.size > 250
           key
         end