diff options
Diffstat (limited to 'synapse/util/caches/descriptors.py')
| -rw-r--r-- | synapse/util/caches/descriptors.py | 77 |
1 files changed, 64 insertions, 13 deletions
diff --git a/synapse/util/caches/descriptors.py b/synapse/util/caches/descriptors.py index f31dfb22b7..5cd277f2f2 100644 --- a/synapse/util/caches/descriptors.py +++ b/synapse/util/caches/descriptors.py @@ -55,7 +55,7 @@ class Cache(object): ) def __init__(self, name, max_entries=1000, keylen=1, lru=True, tree=False): - if lru: + if True: cache_type = TreeCache if tree else dict self.cache = LruCache( max_size=max_entries, keylen=keylen, cache_type=cache_type @@ -81,8 +81,8 @@ class Cache(object): "Cache objects can only be accessed from the main thread" ) - def get(self, key, default=_CacheSentinel): - val = self.cache.get(key, _CacheSentinel) + def get(self, key, default=_CacheSentinel, callback=None): + val = self.cache.get(key, _CacheSentinel, callback=callback) if val is not _CacheSentinel: self.metrics.inc_hits() return val @@ -94,19 +94,19 @@ class Cache(object): else: return default - def update(self, sequence, key, value): + def update(self, sequence, key, value, callback=None): self.check_thread() if self.sequence == sequence: # Only update the cache if the caches sequence number matches the # number that the cache had before the SELECT was started (SYN-369) - self.prefill(key, value) + self.prefill(key, value, callback=callback) - def prefill(self, key, value): + def prefill(self, key, value, callback=None): if self.max_entries is not None: while len(self.cache) >= self.max_entries: - self.cache.popitem(last=False) + self.cache.popitem(last=False, callback=None) - self.cache[key] = value + self.cache.set(key, value, callback=callback) def invalidate(self, key): self.check_thread() @@ -151,6 +151,18 @@ class CacheDescriptor(object): The wrapped function has another additional callable, called "prefill", which can be used to insert values into the cache specifically, without calling the calculation function. + + Cached functions can be "chained" (i.e. a cached function can call other cached + functions and get appropriately invalidated when they called caches are + invalidated) by adding a special "cache_context" argument to the function + and passing that as a kwarg to all caches called. For example:: + + @cachedInlineCallbacks() + def foo(self, key, cache_context): + r1 = yield self.bar1(key, cache_context=cache_context) + r2 = yield self.bar2(key, cache_context=cache_context) + defer.returnValue(r1 + r2) + """ def __init__(self, orig, max_entries=1000, num_args=1, lru=True, tree=False, inlineCallbacks=False): @@ -168,7 +180,13 @@ class CacheDescriptor(object): self.lru = lru self.tree = tree - self.arg_names = inspect.getargspec(orig).args[1:num_args + 1] + all_args = inspect.getargspec(orig) + self.arg_names = all_args.args[1:num_args + 1] + + if "cache_context" in self.arg_names: + self.arg_names.remove("cache_context") + + self.add_cache_context = "cache_context" in all_args.args if len(self.arg_names) < self.num_args: raise Exception( @@ -188,10 +206,23 @@ class CacheDescriptor(object): @functools.wraps(self.orig) def wrapped(*args, **kwargs): + cache_context = kwargs.pop("cache_context", None) + if cache_context: + context_callback = cache_context.invalidate + else: + context_callback = None + + self_context = _CacheContext(cache, None) + if self.add_cache_context: + kwargs["cache_context"] = self_context + arg_dict = inspect.getcallargs(self.orig, obj, *args, **kwargs) cache_key = tuple(arg_dict[arg_nm] for arg_nm in self.arg_names) + + self_context.key = cache_key + try: - cached_result_d = cache.get(cache_key) + cached_result_d = cache.get(cache_key, callback=context_callback) observer = cached_result_d.observe() if DEBUG_CACHES: @@ -228,7 +259,7 @@ class CacheDescriptor(object): ret.addErrback(onErr) ret = ObservableDeferred(ret, consumeErrors=True) - cache.update(sequence, cache_key, ret) + cache.update(sequence, cache_key, ret, callback=context_callback) return preserve_context_over_deferred(ret.observe()) @@ -297,6 +328,12 @@ class CacheListDescriptor(object): @functools.wraps(self.orig) def wrapped(*args, **kwargs): + cache_context = kwargs.pop("cache_context", None) + if cache_context: + context_callback = cache_context.invalidate + else: + context_callback = None + arg_dict = inspect.getcallargs(self.orig, obj, *args, **kwargs) keyargs = [arg_dict[arg_nm] for arg_nm in self.arg_names] list_args = arg_dict[self.list_name] @@ -311,7 +348,7 @@ class CacheListDescriptor(object): key[self.list_pos] = arg try: - res = cache.get(tuple(key)) + res = cache.get(tuple(key), callback=context_callback) if not res.has_succeeded(): res = res.observe() res.addCallback(lambda r, arg: (arg, r), arg) @@ -345,7 +382,10 @@ class CacheListDescriptor(object): key = list(keyargs) key[self.list_pos] = arg - cache.update(sequence, tuple(key), observer) + cache.update( + sequence, tuple(key), observer, + callback=context_callback + ) def invalidate(f, key): cache.invalidate(key) @@ -376,6 +416,17 @@ class CacheListDescriptor(object): return wrapped +class _CacheContext(object): + __slots__ = ["cache", "key"] + + def __init__(self, cache, key): + self.cache = cache + self.key = key + + def invalidate(self): + self.cache.invalidate(self.key) + + def cached(max_entries=1000, num_args=1, lru=True, tree=False): return lambda orig: CacheDescriptor( orig, |