diff --git a/synapse/appservice/api.py b/synapse/appservice/api.py
index 11e9c37c63..00efff1464 100644
--- a/synapse/appservice/api.py
+++ b/synapse/appservice/api.py
@@ -18,7 +18,6 @@ from synapse.api.constants import ThirdPartyEntityKind
from synapse.api.errors import CodeMessageException
from synapse.http.client import SimpleHttpClient
from synapse.events.utils import serialize_event
-from synapse.util.logcontext import preserve_fn, make_deferred_yieldable
from synapse.util.caches.response_cache import ResponseCache
from synapse.types import ThirdPartyInstanceID
@@ -194,12 +193,7 @@ class ApplicationServiceApi(SimpleHttpClient):
defer.returnValue(None)
key = (service.id, protocol)
- result = self.protocol_meta_cache.get(key)
- if not result:
- result = self.protocol_meta_cache.set(
- key, preserve_fn(_get)()
- )
- return make_deferred_yieldable(result)
+ return self.protocol_meta_cache.wrap(key, _get)
@defer.inlineCallbacks
def push_bulk(self, service, events, txn_id=None):
diff --git a/synapse/federation/federation_server.py b/synapse/federation/federation_server.py
index e4ce037acf..d1611f39a9 100644
--- a/synapse/federation/federation_server.py
+++ b/synapse/federation/federation_server.py
@@ -30,7 +30,6 @@ import synapse.metrics
from synapse.types import get_domain_from_id
from synapse.util import async
from synapse.util.caches.response_cache import ResponseCache
-from synapse.util.logcontext import make_deferred_yieldable, preserve_fn
from synapse.util.logutils import log_function
# when processing incoming transactions, we try to handle multiple rooms in
@@ -212,16 +211,11 @@ class FederationServer(FederationBase):
if not in_room:
raise AuthError(403, "Host not in room.")
- result = self._state_resp_cache.get((room_id, event_id))
- if not result:
- with (yield self._server_linearizer.queue((origin, room_id))):
- d = self._state_resp_cache.set(
- (room_id, event_id),
- preserve_fn(self._on_context_state_request_compute)(room_id, event_id)
- )
- resp = yield make_deferred_yieldable(d)
- else:
- resp = yield make_deferred_yieldable(result)
+ resp = yield self._state_resp_cache.wrap(
+ (room_id, event_id),
+ self._on_context_state_request_compute,
+ room_id, event_id,
+ )
defer.returnValue((200, resp))
diff --git a/synapse/handlers/room_list.py b/synapse/handlers/room_list.py
index 8028d793c2..add3f9b009 100644
--- a/synapse/handlers/room_list.py
+++ b/synapse/handlers/room_list.py
@@ -20,7 +20,6 @@ from ._base import BaseHandler
from synapse.api.constants import (
EventTypes, JoinRules,
)
-from synapse.util.logcontext import make_deferred_yieldable, preserve_fn
from synapse.util.async import concurrently_execute
from synapse.util.caches.descriptors import cachedInlineCallbacks
from synapse.util.caches.response_cache import ResponseCache
@@ -78,18 +77,11 @@ class RoomListHandler(BaseHandler):
)
key = (limit, since_token, network_tuple)
- result = self.response_cache.get(key)
- if not result:
- logger.info("No cached result, calculating one.")
- result = self.response_cache.set(
- key,
- preserve_fn(self._get_public_room_list)(
- limit, since_token, network_tuple=network_tuple
- )
- )
- else:
- logger.info("Using cached deferred result.")
- return make_deferred_yieldable(result)
+ return self.response_cache.wrap(
+ key,
+ self._get_public_room_list,
+ limit, since_token, network_tuple=network_tuple,
+ )
@defer.inlineCallbacks
def _get_public_room_list(self, limit=None, since_token=None,
@@ -423,18 +415,14 @@ class RoomListHandler(BaseHandler):
server_name, limit, since_token, include_all_networks,
third_party_instance_id,
)
- result = self.remote_response_cache.get(key)
- if not result:
- result = self.remote_response_cache.set(
- key,
- repl_layer.get_public_rooms(
- server_name, limit=limit, since_token=since_token,
- search_filter=search_filter,
- include_all_networks=include_all_networks,
- third_party_instance_id=third_party_instance_id,
- )
- )
- return result
+ return self.remote_response_cache.wrap(
+ key,
+ repl_layer.get_public_rooms,
+ server_name, limit=limit, since_token=since_token,
+ search_filter=search_filter,
+ include_all_networks=include_all_networks,
+ third_party_instance_id=third_party_instance_id,
+ )
class RoomListNextBatch(namedtuple("RoomListNextBatch", (
diff --git a/synapse/handlers/sync.py b/synapse/handlers/sync.py
index 06d17ab20c..c6946831ab 100644
--- a/synapse/handlers/sync.py
+++ b/synapse/handlers/sync.py
@@ -15,7 +15,7 @@
from synapse.api.constants import Membership, EventTypes
from synapse.util.async import concurrently_execute
-from synapse.util.logcontext import LoggingContext, make_deferred_yieldable, preserve_fn
+from synapse.util.logcontext import LoggingContext
from synapse.util.metrics import Measure, measure_func
from synapse.util.caches.response_cache import ResponseCache
from synapse.push.clientformat import format_push_rules_for_user
@@ -180,15 +180,11 @@ class SyncHandler(object):
Returns:
A Deferred SyncResult.
"""
- result = self.response_cache.get(sync_config.request_key)
- if not result:
- result = self.response_cache.set(
- sync_config.request_key,
- preserve_fn(self._wait_for_sync_for_user)(
- sync_config, since_token, timeout, full_state
- )
- )
- return make_deferred_yieldable(result)
+ return self.response_cache.wrap(
+ sync_config.request_key,
+ self._wait_for_sync_for_user,
+ sync_config, since_token, timeout, full_state,
+ )
@defer.inlineCallbacks
def _wait_for_sync_for_user(self, sync_config, since_token, timeout,
diff --git a/synapse/replication/http/send_event.py b/synapse/replication/http/send_event.py
index c6a6551d24..a9baa2c1c3 100644
--- a/synapse/replication/http/send_event.py
+++ b/synapse/replication/http/send_event.py
@@ -23,7 +23,6 @@ from synapse.events.snapshot import EventContext
from synapse.http.servlet import RestServlet, parse_json_object_from_request
from synapse.util.async import sleep
from synapse.util.caches.response_cache import ResponseCache
-from synapse.util.logcontext import make_deferred_yieldable, preserve_fn
from synapse.util.metrics import Measure
from synapse.types import Requester, UserID
@@ -118,17 +117,12 @@ class ReplicationSendEventRestServlet(RestServlet):
self.response_cache = ResponseCache(hs, "send_event", timeout_ms=30 * 60 * 1000)
def on_PUT(self, request, event_id):
- result = self.response_cache.get(event_id)
- if not result:
- result = self.response_cache.set(
- event_id,
- self._handle_request(request)
- )
- else:
- logger.warn("Returning cached response")
- return make_deferred_yieldable(result)
-
- @preserve_fn
+ return self.response_cache.wrap(
+ event_id,
+ self._handle_request,
+ request
+ )
+
@defer.inlineCallbacks
def _handle_request(self, request):
with Measure(self.clock, "repl_send_event_parse"):
diff --git a/synapse/util/caches/response_cache.py b/synapse/util/caches/response_cache.py
index 066fa423fd..0c2c347953 100644
--- a/synapse/util/caches/response_cache.py
+++ b/synapse/util/caches/response_cache.py
@@ -12,9 +12,13 @@
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
+import logging
from synapse.util.async import ObservableDeferred
from synapse.util.caches import metrics as cache_metrics
+from synapse.util.logcontext import make_deferred_yieldable, run_in_background
+
+logger = logging.getLogger(__name__)
class ResponseCache(object):
@@ -31,6 +35,7 @@ class ResponseCache(object):
self.clock = hs.get_clock()
self.timeout_sec = timeout_ms / 1000.
+ self._name = name
self._metrics = cache_metrics.register_cache(
"response_cache",
size_callback=lambda: self.size(),
@@ -47,7 +52,7 @@ class ResponseCache(object):
so you'll probably want to make_deferred_yieldable it.
Args:
- key (str):
+ key (hashable):
Returns:
twisted.internet.defer.Deferred|None: None if there is no entry
@@ -76,7 +81,7 @@ class ResponseCache(object):
to do it everywhere ResponseCache is used.)
Args:
- key (str):
+ key (hashable):
deferred (twisted.internet.defer.Deferred):
Returns:
@@ -97,3 +102,52 @@ class ResponseCache(object):
result.addBoth(remove)
return result.observe()
+
+ def wrap(self, key, callback, *args, **kwargs):
+ """Wrap together a *get* and *set* call, taking care of logcontexts
+
+ First looks up the key in the cache, and if it is present makes it
+ follow the synapse logcontext rules and returns it.
+
+ Otherwise, makes a call to *callback(*args, **kwargs)*, which should
+ follow the synapse logcontext rules, and adds the result to the cache.
+
+ Example usage:
+
+ @defer.inlineCallbacks
+ def handle_request(request):
+ # etc
+ defer.returnValue(result)
+
+ result = yield response_cache.wrap(
+ key,
+ handle_request,
+ request,
+ )
+
+ Args:
+ key (hashable): key to get/set in the cache
+
+ callback (callable): function to call if the key is not found in
+ the cache
+
+ *args: positional parameters to pass to the callback, if it is used
+
+ **kwargs: named paramters to pass to the callback, if it is used
+
+ Returns:
+ twisted.internet.defer.Deferred: yieldable result
+ """
+ result = self.get(key)
+ if not result:
+ logger.info("[%s]: no cached result for [%s], calculating new one",
+ self._name, key)
+ d = run_in_background(callback, *args, **kwargs)
+ result = self.set(key, d)
+ elif result.called:
+ logger.info("[%s]: using completed cached result for [%s]",
+ self._name, key)
+ else:
+ logger.info("[%s]: using incomplete cached result for [%s]",
+ self._name, key)
+ return make_deferred_yieldable(result)
|
