diff options
Diffstat (limited to 'activesupport/lib/active_support/cache')
| -rw-r--r-- | activesupport/lib/active_support/cache/mem_cache_store.rb | 7 | ||||
| -rw-r--r-- | activesupport/lib/active_support/cache/strategy/local_cache.rb | 104 |
2 files changed, 110 insertions, 1 deletions
diff --git a/activesupport/lib/active_support/cache/mem_cache_store.rb b/activesupport/lib/active_support/cache/mem_cache_store.rb index f9a7fb1440..4d8e1fdd67 100644 --- a/activesupport/lib/active_support/cache/mem_cache_store.rb +++ b/activesupport/lib/active_support/cache/mem_cache_store.rb @@ -13,6 +13,7 @@ module ActiveSupport # server goes down, then MemCacheStore will ignore it until it goes back # online. # - Time-based expiry support. See #write and the +:expires_in+ option. + # - Per-request in memory cache for all communication with the MemCache server(s). class MemCacheStore < Store module Response # :nodoc: STORED = "STORED\r\n" @@ -38,6 +39,8 @@ module ActiveSupport addresses = ["localhost"] if addresses.empty? @addresses = addresses @data = MemCache.new(addresses, options) + + extend Strategy::LocalCache end def read(key, options = nil) # :nodoc: @@ -80,6 +83,7 @@ module ActiveSupport def exist?(key, options = nil) # :nodoc: # Doesn't call super, cause exist? in memcache is in fact a read # But who cares? Reading is very fast anyway + # Local cache is checked first, if it doesn't know then memcache itself is read from !read(key, options).nil? end @@ -94,7 +98,6 @@ module ActiveSupport def decrement(key, amount = 1) # :nodoc: log("decrement", key, amount) - response = @data.decr(key, amount) response == Response::NOT_FOUND ? nil : response rescue MemCache::MemCacheError @@ -102,6 +105,8 @@ module ActiveSupport end def delete_matched(matcher, options = nil) # :nodoc: + # don't do any local caching at present, just pass + # through and let the error happen super raise "Not supported by Memcache" end diff --git a/activesupport/lib/active_support/cache/strategy/local_cache.rb b/activesupport/lib/active_support/cache/strategy/local_cache.rb new file mode 100644 index 0000000000..621358d701 --- /dev/null +++ b/activesupport/lib/active_support/cache/strategy/local_cache.rb @@ -0,0 +1,104 @@ +module ActiveSupport + module Cache + module Strategy + module LocalCache + # this allows caching of the fact that there is nothing in the remote cache + NULL = 'remote_cache_store:null' + + def with_local_cache + Thread.current[thread_local_key] = MemoryStore.new + yield + ensure + Thread.current[thread_local_key] = nil + end + + def middleware + @middleware ||= begin + klass = Class.new + klass.class_eval(<<-EOS, __FILE__, __LINE__) + def initialize(app) + @app = app + end + + def call(env) + Thread.current[:#{thread_local_key}] = MemoryStore.new + @app.call(env) + ensure + Thread.current[:#{thread_local_key}] = nil + end + EOS + klass + end + end + + def read(key, options = nil) + value = local_cache && local_cache.read(key) + if value == NULL + nil + elsif value.nil? + value = super + local_cache.write(key, value || NULL) if local_cache + value + else + # forcing the value to be immutable + value.dup + end + end + + def write(key, value, options = nil) + value = value.to_s if respond_to?(:raw?) && raw?(options) + local_cache.write(key, value || NULL) if local_cache + super + end + + def delete(key, options = nil) + local_cache.write(key, NULL) if local_cache + super + end + + def exist(key, options = nil) + value = local_cache.read(key) if local_cache + if value == NULL + false + elsif value + true + else + super + end + end + + def increment(key, amount = 1) + if value = super + local_cache.write(key, value.to_s) if local_cache + value + else + nil + end + end + + def decrement(key, amount = 1) + if value = super + local_cache.write(key, value.to_s) if local_cache + value + else + nil + end + end + + def clear + local_cache.clear if local_cache + super + end + + private + def thread_local_key + @thread_local_key ||= "#{self.class.name.underscore}_local_cache".gsub("/", "_").to_sym + end + + def local_cache + Thread.current[thread_local_key] + end + end + end + end +end |