default_serializer

# File activesupport/lib/active_support/cache/mem_cache_store.rb, line 225
        def default_serializer
          if Cache.format_version == 6.1
            ActiveSupport.deprecator.warn <<~EOM
              Support for `config.active_support.cache_format_version = 6.1` has been deprecated and will be removed in Rails 7.2.

              Check the Rails upgrade guide at https://guides.rubyonrails.org/upgrading_ruby_on_rails.html#new-activesupport-cache-serialization-format
              for more information on how to upgrade.
            EOM
            Cache::SerializerWithFallback[:passthrough]
          else
            super
          end
        end

        # Read an entry from the cache.
        def read_entry(key, **options)
          deserialize_entry(read_serialized_entry(key, **options), **options)
        end

        def read_serialized_entry(key, **options)
          rescue_error_with(nil) do
            @data.with { |c| c.get(key, options) }
          end
        end

        # Write an entry to the cache.
        def write_entry(key, entry, **options)
          write_serialized_entry(key, serialize_entry(entry, **options), **options)
        end

        def write_serialized_entry(key, payload, **options)
          method = options[:unless_exist] ? :add : :set
          expires_in = options[:expires_in].to_i
          if options[:race_condition_ttl] && 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
          rescue_error_with false do
            # Don't pass compress option to Dalli since we are already dealing with compression.
            options.delete(:compress)
            @data.with { |c| c.send(method, key, payload, expires_in, **options) }
          end
        end

        # Reads multiple entries from the cache implementation.
        def read_multi_entries(names, **options)
          keys_to_names = names.index_by { |name| normalize_key(name, options) }

          raw_values = begin
            @data.with { |c| c.get_multi(keys_to_names.keys) }
          rescue Dalli::UnmarshalError
            {}
          end

          values = {}

          raw_values.each do |key, value|
            entry = deserialize_entry(value, raw: options[:raw])

            unless entry.nil? || entry.expired? || entry.mismatched?(normalize_version(keys_to_names[key], options))
              begin
                values[keys_to_names[key]] = entry.value
              rescue DeserializationError
              end
            end
          end

          values
        end

        # Delete an entry from the cache.
        def delete_entry(key, **options)
          rescue_error_with(false) { @data.with { |c| c.delete(key) } }
        end

        def serialize_entry(entry, raw: false, **options)
          if raw
            entry.value.to_s
          else
            super(entry, raw: raw, **options)
          end
        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
        # characters properly.
        def normalize_key(key, options)
          key = super
          if key
            key = key.dup.force_encoding(Encoding::ASCII_8BIT)
            key = key.gsub(ESCAPE_KEY_CHARS) { |match| "%#{match.getbyte(0).to_s(16).upcase}" }

            if key.size > KEY_MAX_SIZE
              key_separator = ":hash:"
              key_hash = ActiveSupport::Digest.hexdigest(key)
              key_trim_size = KEY_MAX_SIZE - key_separator.size - key_hash.size
              key = "#{key[0, key_trim_size]}#{key_separator}#{key_hash}"
            end
          end
          key
        end

        def deserialize_entry(payload, raw: false, **)
          if payload && raw
            Entry.new(payload)
          else
            super(payload)
          end
        end

        def rescue_error_with(fallback)
          yield
        rescue Dalli::DalliError => error
          logger.error("DalliError (#{error}): #{error.message}") if logger
          ActiveSupport.error_reporter&.report(
            error,
            severity: :warning,
            source: "mem_cache_store.active_support",
          )
          fallback
        end
    end
  end