require 'memcache' module ActiveSupport module Cache class MemCacheStore < Store module Response STORED = "STORED\r\n" NOT_STORED = "NOT_STORED\r\n" EXISTS = "EXISTS\r\n" NOT_FOUND = "NOT_FOUND\r\n" DELETED = "DELETED\r\n" end attr_reader :addresses def initialize(*addresses) addresses = addresses.flatten options = addresses.extract_options! addresses = ["localhost"] if addresses.empty? @addresses = addresses @data = MemCache.new(addresses, options) end def read(key, options = nil) super @data.get(key, raw?(options)) rescue MemCache::MemCacheError => e logger.error("MemCacheError (#{e}): #{e.message}") nil end # Set key = value. Pass :unless_exist => true if you don't # want to update the cache if the key is already set. def write(key, value, options = nil) super method = options && options[:unless_exist] ? :add : :set response = @data.send(method, key, value, expires_in(options), raw?(options)) response == Response::STORED rescue MemCache::MemCacheError => e logger.error("MemCacheError (#{e}): #{e.message}") false end def delete(key, options = nil) super response = @data.delete(key, expires_in(options)) response == Response::DELETED rescue MemCache::MemCacheError => e logger.error("MemCacheError (#{e}): #{e.message}") false end def exist?(key, options = nil) # Doesn't call super, cause exist? in memcache is in fact a read # But who cares? Reading is very fast anyway !read(key, options).nil? end def increment(key, amount = 1) log("incrementing", key, amount) response = @data.incr(key, amount) response == Response::NOT_FOUND ? nil : response rescue MemCache::MemCacheError nil end def decrement(key, amount = 1) log("decrement", key, amount) response = data.decr(key, amount) response == Response::NOT_FOUND ? nil : response rescue MemCache::MemCacheError nil end def delete_matched(matcher, options = nil) super raise "Not supported by Memcache" end def clear @data.flush_all end def stats @data.stats end private def expires_in(options) (options && options[:expires_in]) || 0 end def raw?(options) options && options[:raw] end end end end