Merge branch 'develop' of https://github.com/matrix-org/synapse into cohort_analytics

synapse/__init__.py

@@ -16,4 +16,4 @@
 """ This is a reference implementation of a Matrix home server.
 """
 
-__version__ = "0.28.0-rc1"
+__version__ = "0.28.1"

synapse/api/constants.py

@@ -16,6 +16,9 @@
 
 """Contains constants from the specification."""
 
+# the "depth" field on events is limited to 2**63 - 1
+MAX_DEPTH = 2**63 - 1
+
 
 class Membership(object):
 

synapse/app/appservice.py

@@ -32,10 +32,10 @@ from synapse.replication.tcp.client import ReplicationClientHandler
 from synapse.server import HomeServer
 from synapse.storage.engines import create_engine
 from synapse.util.httpresourcetree import create_resource_tree
-from synapse.util.logcontext import LoggingContext, preserve_fn
+from synapse.util.logcontext import LoggingContext, run_in_background
 from synapse.util.manhole import manhole
 from synapse.util.versionstring import get_version_string
-from twisted.internet import reactor
+from twisted.internet import reactor, defer
 from twisted.web.resource import NoResource
 
 logger = logging.getLogger("synapse.app.appservice")
@@ -74,6 +74,7 @@ class AppserviceServer(HomeServer):
                 site_tag,
                 listener_config,
                 root_resource,
+                self.version_string,
             )
         )
 
@@ -112,9 +113,14 @@ class ASReplicationHandler(ReplicationClientHandler):
 
         if stream_name == "events":
             max_stream_id = self.store.get_room_max_stream_ordering()
-            preserve_fn(
-                self.appservice_handler.notify_interested_services
-            )(max_stream_id)
+            run_in_background(self._notify_app_services, max_stream_id)
+
+    @defer.inlineCallbacks
+    def _notify_app_services(self, room_stream_id):
+        try:
+            yield self.appservice_handler.notify_interested_services(room_stream_id)
+        except Exception:
+            logger.exception("Error notifying application services of event")
 
 
 def start(config_options):

synapse/app/client_reader.py

@@ -98,6 +98,7 @@ class ClientReaderServer(HomeServer):
                 site_tag,
                 listener_config,
                 root_resource,
+                self.version_string,
             )
         )
 

synapse/app/event_creator.py

@@ -114,6 +114,7 @@ class EventCreatorServer(HomeServer):
                 site_tag,
                 listener_config,
                 root_resource,
+                self.version_string,
             )
         )
 

synapse/app/federation_reader.py

@@ -87,6 +87,7 @@ class FederationReaderServer(HomeServer):
                 site_tag,
                 listener_config,
                 root_resource,
+                self.version_string,
             )
         )
 

synapse/app/federation_sender.py

@@ -38,7 +38,7 @@ from synapse.server import HomeServer
 from synapse.storage.engines import create_engine
 from synapse.util.async import Linearizer
 from synapse.util.httpresourcetree import create_resource_tree
-from synapse.util.logcontext import LoggingContext, preserve_fn
+from synapse.util.logcontext import LoggingContext, run_in_background
 from synapse.util.manhole import manhole
 from synapse.util.versionstring import get_version_string
 from twisted.internet import defer, reactor
@@ -101,6 +101,7 @@ class FederationSenderServer(HomeServer):
                 site_tag,
                 listener_config,
                 root_resource,
+                self.version_string,
             )
         )
 
@@ -229,7 +230,7 @@ class FederationSenderHandler(object):
         # presence, typing, etc.
         if stream_name == "federation":
             send_queue.process_rows_for_federation(self.federation_sender, rows)
-            preserve_fn(self.update_token)(token)
+            run_in_background(self.update_token, token)
 
         # We also need to poke the federation sender when new events happen
         elif stream_name == "events":
@@ -237,19 +238,22 @@ class FederationSenderHandler(object):
 
     @defer.inlineCallbacks
     def update_token(self, token):
-        self.federation_position = token
+        try:
+            self.federation_position = token
 
-        # We linearize here to ensure we don't have races updating the token
-        with (yield self._fed_position_linearizer.queue(None)):
-            if self._last_ack < self.federation_position:
-                yield self.store.update_federation_out_pos(
-                    "federation", self.federation_position
-                )
+            # We linearize here to ensure we don't have races updating the token
+            with (yield self._fed_position_linearizer.queue(None)):
+                if self._last_ack < self.federation_position:
+                    yield self.store.update_federation_out_pos(
+                        "federation", self.federation_position
+                    )
 
-                # We ACK this token over replication so that the master can drop
-                # its in memory queues
-                self.replication_client.send_federation_ack(self.federation_position)
-                self._last_ack = self.federation_position
+                    # We ACK this token over replication so that the master can drop
+                    # its in memory queues
+                    self.replication_client.send_federation_ack(self.federation_position)
+                    self._last_ack = self.federation_position
+        except Exception:
+            logger.exception("Error updating federation stream position")
 
 
 if __name__ == '__main__':

synapse/app/frontend_proxy.py

@@ -152,6 +152,7 @@ class FrontendProxyServer(HomeServer):
                 site_tag,
                 listener_config,
                 root_resource,
+                self.version_string,
             )
         )
 

synapse/app/homeserver.py

@@ -140,6 +140,7 @@ class SynapseHomeServer(HomeServer):
                     site_tag,
                     listener_config,
                     root_resource,
+                    self.version_string,
                 ),
                 self.tls_server_context_factory,
             )
@@ -153,6 +154,7 @@ class SynapseHomeServer(HomeServer):
                     site_tag,
                     listener_config,
                     root_resource,
+                    self.version_string,
                 )
             )
         logger.info("Synapse now listening on port %d", port)

synapse/app/media_repository.py

@@ -94,6 +94,7 @@ class MediaRepositoryServer(HomeServer):
                 site_tag,
                 listener_config,
                 root_resource,
+                self.version_string,
             )
         )
 

synapse/app/pusher.py

@@ -33,7 +33,7 @@ from synapse.server import HomeServer
 from synapse.storage import DataStore
 from synapse.storage.engines import create_engine
 from synapse.util.httpresourcetree import create_resource_tree
-from synapse.util.logcontext import LoggingContext, preserve_fn
+from synapse.util.logcontext import LoggingContext, run_in_background
 from synapse.util.manhole import manhole
 from synapse.util.versionstring import get_version_string
 from twisted.internet import defer, reactor
@@ -104,6 +104,7 @@ class PusherServer(HomeServer):
                 site_tag,
                 listener_config,
                 root_resource,
+                self.version_string,
             )
         )
 
@@ -140,24 +141,27 @@ class PusherReplicationHandler(ReplicationClientHandler):
 
     def on_rdata(self, stream_name, token, rows):
         super(PusherReplicationHandler, self).on_rdata(stream_name, token, rows)
-        preserve_fn(self.poke_pushers)(stream_name, token, rows)
+        run_in_background(self.poke_pushers, stream_name, token, rows)
 
     @defer.inlineCallbacks
     def poke_pushers(self, stream_name, token, rows):
-        if stream_name == "pushers":
-            for row in rows:
-                if row.deleted:
-                    yield self.stop_pusher(row.user_id, row.app_id, row.pushkey)
-                else:
-                    yield self.start_pusher(row.user_id, row.app_id, row.pushkey)
-        elif stream_name == "events":
-            yield self.pusher_pool.on_new_notifications(
-                token, token,
-            )
-        elif stream_name == "receipts":
-            yield self.pusher_pool.on_new_receipts(
-                token, token, set(row.room_id for row in rows)
-            )
+        try:
+            if stream_name == "pushers":
+                for row in rows:
+                    if row.deleted:
+                        yield self.stop_pusher(row.user_id, row.app_id, row.pushkey)
+                    else:
+                        yield self.start_pusher(row.user_id, row.app_id, row.pushkey)
+            elif stream_name == "events":
+                yield self.pusher_pool.on_new_notifications(
+                    token, token,
+                )
+            elif stream_name == "receipts":
+                yield self.pusher_pool.on_new_receipts(
+                    token, token, set(row.room_id for row in rows)
+                )
+        except Exception:
+            logger.exception("Error poking pushers")
 
     def stop_pusher(self, user_id, app_id, pushkey):
         key = "%s:%s" % (app_id, pushkey)

synapse/app/synchrotron.py

@@ -51,7 +51,7 @@ from synapse.storage.engines import create_engine
 from synapse.storage.presence import UserPresenceState
 from synapse.storage.roommember import RoomMemberStore
 from synapse.util.httpresourcetree import create_resource_tree
-from synapse.util.logcontext import LoggingContext, preserve_fn
+from synapse.util.logcontext import LoggingContext, run_in_background
 from synapse.util.manhole import manhole
 from synapse.util.stringutils import random_string
 from synapse.util.versionstring import get_version_string
@@ -281,6 +281,7 @@ class SynchrotronServer(HomeServer):
                 site_tag,
                 listener_config,
                 root_resource,
+                self.version_string,
             )
         )
 
@@ -327,8 +328,7 @@ class SyncReplicationHandler(ReplicationClientHandler):
 
     def on_rdata(self, stream_name, token, rows):
         super(SyncReplicationHandler, self).on_rdata(stream_name, token, rows)
-
-        preserve_fn(self.process_and_notify)(stream_name, token, rows)
+        run_in_background(self.process_and_notify, stream_name, token, rows)
 
     def get_streams_to_replicate(self):
         args = super(SyncReplicationHandler, self).get_streams_to_replicate()
@@ -340,55 +340,58 @@ class SyncReplicationHandler(ReplicationClientHandler):
 
     @defer.inlineCallbacks
     def process_and_notify(self, stream_name, token, rows):
-        if stream_name == "events":
-            # We shouldn't get multiple rows per token for events stream, so
-            # we don't need to optimise this for multiple rows.
-            for row in rows:
-                event = yield self.store.get_event(row.event_id)
-                extra_users = ()
-                if event.type == EventTypes.Member:
-                    extra_users = (event.state_key,)
-                max_token = self.store.get_room_max_stream_ordering()
-                self.notifier.on_new_room_event(
-                    event, token, max_token, extra_users
-                )
-        elif stream_name == "push_rules":
-            self.notifier.on_new_event(
-                "push_rules_key", token, users=[row.user_id for row in rows],
-            )
-        elif stream_name in ("account_data", "tag_account_data",):
-            self.notifier.on_new_event(
-                "account_data_key", token, users=[row.user_id for row in rows],
-            )
-        elif stream_name == "receipts":
-            self.notifier.on_new_event(
-                "receipt_key", token, rooms=[row.room_id for row in rows],
-            )
-        elif stream_name == "typing":
-            self.typing_handler.process_replication_rows(token, rows)
-            self.notifier.on_new_event(
-                "typing_key", token, rooms=[row.room_id for row in rows],
-            )
-        elif stream_name == "to_device":
-            entities = [row.entity for row in rows if row.entity.startswith("@")]
-            if entities:
+        try:
+            if stream_name == "events":
+                # We shouldn't get multiple rows per token for events stream, so
+                # we don't need to optimise this for multiple rows.
+                for row in rows:
+                    event = yield self.store.get_event(row.event_id)
+                    extra_users = ()
+                    if event.type == EventTypes.Member:
+                        extra_users = (event.state_key,)
+                    max_token = self.store.get_room_max_stream_ordering()
+                    self.notifier.on_new_room_event(
+                        event, token, max_token, extra_users
+                    )
+            elif stream_name == "push_rules":
                 self.notifier.on_new_event(
-                    "to_device_key", token, users=entities,
+                    "push_rules_key", token, users=[row.user_id for row in rows],
                 )
-        elif stream_name == "device_lists":
-            all_room_ids = set()
-            for row in rows:
-                room_ids = yield self.store.get_rooms_for_user(row.user_id)
-                all_room_ids.update(room_ids)
-            self.notifier.on_new_event(
-                "device_list_key", token, rooms=all_room_ids,
-            )
-        elif stream_name == "presence":
-            yield self.presence_handler.process_replication_rows(token, rows)
-        elif stream_name == "receipts":
-            self.notifier.on_new_event(
-                "groups_key", token, users=[row.user_id for row in rows],
-            )
+            elif stream_name in ("account_data", "tag_account_data",):
+                self.notifier.on_new_event(
+                    "account_data_key", token, users=[row.user_id for row in rows],
+                )
+            elif stream_name == "receipts":
+                self.notifier.on_new_event(
+                    "receipt_key", token, rooms=[row.room_id for row in rows],
+                )
+            elif stream_name == "typing":
+                self.typing_handler.process_replication_rows(token, rows)
+                self.notifier.on_new_event(
+                    "typing_key", token, rooms=[row.room_id for row in rows],
+                )
+            elif stream_name == "to_device":
+                entities = [row.entity for row in rows if row.entity.startswith("@")]
+                if entities:
+                    self.notifier.on_new_event(
+                        "to_device_key", token, users=entities,
+                    )
+            elif stream_name == "device_lists":
+                all_room_ids = set()
+                for row in rows:
+                    room_ids = yield self.store.get_rooms_for_user(row.user_id)
+                    all_room_ids.update(room_ids)
+                self.notifier.on_new_event(
+                    "device_list_key", token, rooms=all_room_ids,
+                )
+            elif stream_name == "presence":
+                yield self.presence_handler.process_replication_rows(token, rows)
+            elif stream_name == "receipts":
+                self.notifier.on_new_event(
+                    "groups_key", token, users=[row.user_id for row in rows],
+                )
+        except Exception:
+            logger.exception("Error processing replication")
 
 
 def start(config_options):

synapse/app/user_dir.py

@@ -39,10 +39,10 @@ from synapse.storage.engines import create_engine
 from synapse.storage.user_directory import UserDirectoryStore
 from synapse.util.caches.stream_change_cache import StreamChangeCache
 from synapse.util.httpresourcetree import create_resource_tree
-from synapse.util.logcontext import LoggingContext, preserve_fn
+from synapse.util.logcontext import LoggingContext, run_in_background
 from synapse.util.manhole import manhole
 from synapse.util.versionstring import get_version_string
-from twisted.internet import reactor
+from twisted.internet import reactor, defer
 from twisted.web.resource import NoResource
 
 logger = logging.getLogger("synapse.app.user_dir")
@@ -126,6 +126,7 @@ class UserDirectoryServer(HomeServer):
                 site_tag,
                 listener_config,
                 root_resource,
+                self.version_string,
             )
         )
 
@@ -164,7 +165,14 @@ class UserDirectoryReplicationHandler(ReplicationClientHandler):
             stream_name, token, rows
         )
         if stream_name == "current_state_deltas":
-            preserve_fn(self.user_directory.notify_new_event)()
+            run_in_background(self._notify_directory)
+
+    @defer.inlineCallbacks
+    def _notify_directory(self):
+        try:
+            yield self.user_directory.notify_new_event()
+        except Exception:
+            logger.exception("Error notifiying user directory of state update")
 
 
 def start(config_options):

synapse/appservice/scheduler.py

@@ -51,7 +51,7 @@ components.
 from twisted.internet import defer
 
 from synapse.appservice import ApplicationServiceState
-from synapse.util.logcontext import preserve_fn
+from synapse.util.logcontext import run_in_background
 from synapse.util.metrics import Measure
 
 import logging
@@ -106,7 +106,7 @@ class _ServiceQueuer(object):
     def enqueue(self, service, event):
         # if this service isn't being sent something
         self.queued_events.setdefault(service.id, []).append(event)
-        preserve_fn(self._send_request)(service)
+        run_in_background(self._send_request, service)
 
     @defer.inlineCallbacks
     def _send_request(self, service):
@@ -152,10 +152,10 @@ class _TransactionController(object):
                 if sent:
                     yield txn.complete(self.store)
                 else:
-                    preserve_fn(self._start_recoverer)(service)
-        except Exception as e:
-            logger.exception(e)
-            preserve_fn(self._start_recoverer)(service)
+                    run_in_background(self._start_recoverer, service)
+        except Exception:
+            logger.exception("Error creating appservice transaction")
+            run_in_background(self._start_recoverer, service)
 
     @defer.inlineCallbacks
     def on_recovered(self, recoverer):
@@ -176,17 +176,20 @@ class _TransactionController(object):
 
     @defer.inlineCallbacks
     def _start_recoverer(self, service):
-        yield self.store.set_appservice_state(
-            service,
-            ApplicationServiceState.DOWN
-        )
-        logger.info(
-            "Application service falling behind. Starting recoverer. AS ID %s",
-            service.id
-        )
-        recoverer = self.recoverer_fn(service, self.on_recovered)
-        self.add_recoverers([recoverer])
-        recoverer.recover()
+        try:
+            yield self.store.set_appservice_state(
+                service,
+                ApplicationServiceState.DOWN
+            )
+            logger.info(
+                "Application service falling behind. Starting recoverer. AS ID %s",
+                service.id
+            )
+            recoverer = self.recoverer_fn(service, self.on_recovered)
+            self.add_recoverers([recoverer])
+            recoverer.recover()
+        except Exception:
+            logger.exception("Error starting AS recoverer")
 
     @defer.inlineCallbacks
     def _is_service_up(self, service):

synapse/config/_base.py

@@ -281,15 +281,15 @@ class Config(object):
                     )
                 if not cls.path_exists(config_dir_path):
                     os.makedirs(config_dir_path)
-                with open(config_path, "wb") as config_file:
-                    config_bytes, config = obj.generate_config(
+                with open(config_path, "w") as config_file:
+                    config_str, config = obj.generate_config(
                         config_dir_path=config_dir_path,
                         server_name=server_name,
                         report_stats=(config_args.report_stats == "yes"),
                         is_generating_file=True
                     )
                     obj.invoke_all("generate_files", config)
-                    config_file.write(config_bytes)
+                    config_file.write(config_str)
                 print((
                     "A config file has been generated in %r for server name"
                     " %r with corresponding SSL keys and self-signed"

synapse/config/appservice.py

@@ -17,11 +17,11 @@ from ._base import Config, ConfigError
 from synapse.appservice import ApplicationService
 from synapse.types import UserID
 
-import urllib
 import yaml
 import logging
 
 from six import string_types
+from six.moves.urllib import parse as urlparse
 
 logger = logging.getLogger(__name__)
 
@@ -105,7 +105,7 @@ def _load_appservice(hostname, as_info, config_filename):
         )
 
     localpart = as_info["sender_localpart"]
-    if urllib.quote(localpart) != localpart:
+    if urlparse.quote(localpart) != localpart:
         raise ValueError(
             "sender_localpart needs characters which are not URL encoded."
         )

synapse/config/logger.py

@@ -117,7 +117,7 @@ class LoggingConfig(Config):
         log_config = config.get("log_config")
         if log_config and not os.path.exists(log_config):
             log_file = self.abspath("homeserver.log")
-            with open(log_config, "wb") as log_config_file:
+            with open(log_config, "w") as log_config_file:
                 log_config_file.write(
                     DEFAULT_LOG_CONFIG.substitute(log_file=log_file)
                 )

synapse/config/tls.py

@@ -133,7 +133,7 @@ class TlsConfig(Config):
         tls_dh_params_path = config["tls_dh_params_path"]
 
         if not self.path_exists(tls_private_key_path):
-            with open(tls_private_key_path, "w") as private_key_file:
+            with open(tls_private_key_path, "wb") as private_key_file:
                 tls_private_key = crypto.PKey()
                 tls_private_key.generate_key(crypto.TYPE_RSA, 2048)
                 private_key_pem = crypto.dump_privatekey(
@@ -148,7 +148,7 @@ class TlsConfig(Config):
                 )
 
         if not self.path_exists(tls_certificate_path):
-            with open(tls_certificate_path, "w") as certificate_file:
+            with open(tls_certificate_path, "wb") as certificate_file:
                 cert = crypto.X509()
                 subject = cert.get_subject()
                 subject.CN = config["server_name"]

synapse/crypto/context_factory.py

@@ -13,8 +13,8 @@
 # limitations under the License.
 
 from twisted.internet import ssl
-from OpenSSL import SSL
-from twisted.internet._sslverify import _OpenSSLECCurve, _defaultCurveName
+from OpenSSL import SSL, crypto
+from twisted.internet._sslverify import _defaultCurveName
 
 import logging
 
@@ -32,8 +32,9 @@ class ServerContextFactory(ssl.ContextFactory):
     @staticmethod
     def configure_context(context, config):
         try:
-            _ecCurve = _OpenSSLECCurve(_defaultCurveName)
-            _ecCurve.addECKeyToContext(context)
+            _ecCurve = crypto.get_elliptic_curve(_defaultCurveName)
+            context.set_tmp_ecdh(_ecCurve)
+
         except Exception:
             logger.exception("Failed to enable elliptic curve for TLS")
         context.set_options(SSL.OP_NO_SSLv2 | SSL.OP_NO_SSLv3)

synapse/crypto/keyring.py

@@ -19,7 +19,8 @@ from synapse.api.errors import SynapseError, Codes
 from synapse.util import unwrapFirstError, logcontext
 from synapse.util.logcontext import (
     PreserveLoggingContext,
-    preserve_fn
+    preserve_fn,
+    run_in_background,
 )
 from synapse.util.metrics import Measure
 
@@ -127,7 +128,7 @@ class Keyring(object):
 
             verify_requests.append(verify_request)
 
-        preserve_fn(self._start_key_lookups)(verify_requests)
+        run_in_background(self._start_key_lookups, verify_requests)
 
         # Pass those keys to handle_key_deferred so that the json object
         # signatures can be verified
@@ -146,53 +147,56 @@ class Keyring(object):
             verify_requests (List[VerifyKeyRequest]):
         """
 
-        # create a deferred for each server we're going to look up the keys
-        # for; we'll resolve them once we have completed our lookups.
-        # These will be passed into wait_for_previous_lookups to block
-        # any other lookups until we have finished.
-        # The deferreds are called with no logcontext.
-        server_to_deferred = {
-            rq.server_name: defer.Deferred()
-            for rq in verify_requests
-        }
+        try:
+            # create a deferred for each server we're going to look up the keys
+            # for; we'll resolve them once we have completed our lookups.
+            # These will be passed into wait_for_previous_lookups to block
+            # any other lookups until we have finished.
+            # The deferreds are called with no logcontext.
+            server_to_deferred = {
+                rq.server_name: defer.Deferred()
+                for rq in verify_requests
+            }
 
-        # We want to wait for any previous lookups to complete before
-        # proceeding.
-        yield self.wait_for_previous_lookups(
-            [rq.server_name for rq in verify_requests],
-            server_to_deferred,
-        )
-
-        # Actually start fetching keys.
-        self._get_server_verify_keys(verify_requests)
-
-        # When we've finished fetching all the keys for a given server_name,
-        # resolve the deferred passed to `wait_for_previous_lookups` so that
-        # any lookups waiting will proceed.
-        #
-        # map from server name to a set of request ids
-        server_to_request_ids = {}
-
-        for verify_request in verify_requests:
-            server_name = verify_request.server_name
-            request_id = id(verify_request)
-            server_to_request_ids.setdefault(server_name, set()).add(request_id)
-
-        def remove_deferreds(res, verify_request):
-            server_name = verify_request.server_name
-            request_id = id(verify_request)
-            server_to_request_ids[server_name].discard(request_id)
-            if not server_to_request_ids[server_name]:
-                d = server_to_deferred.pop(server_name, None)
-                if d:
-                    d.callback(None)
-            return res
-
-        for verify_request in verify_requests:
-            verify_request.deferred.addBoth(
-                remove_deferreds, verify_request,
+            # We want to wait for any previous lookups to complete before
+            # proceeding.
+            yield self.wait_for_previous_lookups(
+                [rq.server_name for rq in verify_requests],
+                server_to_deferred,
             )
 
+            # Actually start fetching keys.
+            self._get_server_verify_keys(verify_requests)
+
+            # When we've finished fetching all the keys for a given server_name,
+            # resolve the deferred passed to `wait_for_previous_lookups` so that
+            # any lookups waiting will proceed.
+            #
+            # map from server name to a set of request ids
+            server_to_request_ids = {}
+
+            for verify_request in verify_requests:
+                server_name = verify_request.server_name
+                request_id = id(verify_request)
+                server_to_request_ids.setdefault(server_name, set()).add(request_id)
+
+            def remove_deferreds(res, verify_request):
+                server_name = verify_request.server_name
+                request_id = id(verify_request)
+                server_to_request_ids[server_name].discard(request_id)
+                if not server_to_request_ids[server_name]:
+                    d = server_to_deferred.pop(server_name, None)
+                    if d:
+                        d.callback(None)
+                return res
+
+            for verify_request in verify_requests:
+                verify_request.deferred.addBoth(
+                    remove_deferreds, verify_request,
+                )
+        except Exception:
+            logger.exception("Error starting key lookups")
+
     @defer.inlineCallbacks
     def wait_for_previous_lookups(self, server_names, server_to_deferred):
         """Waits for any previous key lookups for the given servers to finish.
@@ -313,7 +317,7 @@ class Keyring(object):
                     if not verify_request.deferred.called:
                         verify_request.deferred.errback(err)
 
-        preserve_fn(do_iterations)().addErrback(on_err)
+        run_in_background(do_iterations).addErrback(on_err)
 
     @defer.inlineCallbacks
     def get_keys_from_store(self, server_name_and_key_ids):
@@ -329,8 +333,9 @@ class Keyring(object):
         """
         res = yield logcontext.make_deferred_yieldable(defer.gatherResults(
             [
-                preserve_fn(self.store.get_server_verify_keys)(
-                    server_name, key_ids
+                run_in_background(
+                    self.store.get_server_verify_keys,
+                    server_name, key_ids,
                 ).addCallback(lambda ks, server: (server, ks), server_name)
                 for server_name, key_ids in server_name_and_key_ids
             ],
@@ -358,7 +363,7 @@ class Keyring(object):
 
         results = yield logcontext.make_deferred_yieldable(defer.gatherResults(
             [
-                preserve_fn(get_key)(p_name, p_keys)
+                run_in_background(get_key, p_name, p_keys)
                 for p_name, p_keys in self.perspective_servers.items()
             ],
             consumeErrors=True,
@@ -398,7 +403,7 @@ class Keyring(object):
 
         results = yield logcontext.make_deferred_yieldable(defer.gatherResults(
             [
-                preserve_fn(get_key)(server_name, key_ids)
+                run_in_background(get_key, server_name, key_ids)
                 for server_name, key_ids in server_name_and_key_ids
             ],
             consumeErrors=True,
@@ -481,7 +486,8 @@ class Keyring(object):
 
         yield logcontext.make_deferred_yieldable(defer.gatherResults(
             [
-                preserve_fn(self.store_keys)(
+                run_in_background(
+                    self.store_keys,
                     server_name=server_name,
                     from_server=perspective_name,
                     verify_keys=response_keys,
@@ -539,7 +545,8 @@ class Keyring(object):
 
         yield logcontext.make_deferred_yieldable(defer.gatherResults(
             [
-                preserve_fn(self.store_keys)(
+                run_in_background(
+                    self.store_keys,
                     server_name=key_server_name,
                     from_server=server_name,
                     verify_keys=verify_keys,
@@ -615,7 +622,8 @@ class Keyring(object):
 
         yield logcontext.make_deferred_yieldable(defer.gatherResults(
             [
-                preserve_fn(self.store.store_server_keys_json)(
+                run_in_background(
+                    self.store.store_server_keys_json,
                     server_name=server_name,
                     key_id=key_id,
                     from_server=server_name,
@@ -716,7 +724,8 @@ class Keyring(object):
         # TODO(markjh): Store whether the keys have expired.
         return logcontext.make_deferred_yieldable(defer.gatherResults(
             [
-                preserve_fn(self.store.store_server_verify_key)(
+                run_in_background(
+                    self.store.store_server_verify_key,
                     server_name, server_name, key.time_added, key
                 )
                 for key_id, key in verify_keys.items()

synapse/events/__init__.py

@@ -47,14 +47,26 @@ class _EventInternalMetadata(object):
 
 
 def _event_dict_property(key):
+    # We want to be able to use hasattr with the event dict properties.
+    # However, (on python3) hasattr expects AttributeError to be raised. Hence,
+    # we need to transform the KeyError into an AttributeError
     def getter(self):
-        return self._event_dict[key]
+        try:
+            return self._event_dict[key]
+        except KeyError:
+            raise AttributeError(key)
 
     def setter(self, v):
-        self._event_dict[key] = v
+        try:
+            self._event_dict[key] = v
+        except KeyError:
+            raise AttributeError(key)
 
     def delete(self):
-        del self._event_dict[key]
+        try:
+            del self._event_dict[key]
+        except KeyError:
+            raise AttributeError(key)
 
     return property(
         getter,

synapse/federation/federation_base.py

@@ -14,7 +14,10 @@
 # limitations under the License.
 import logging
 
-from synapse.api.errors import SynapseError
+import six
+
+from synapse.api.constants import MAX_DEPTH
+from synapse.api.errors import SynapseError, Codes
 from synapse.crypto.event_signing import check_event_content_hash
 from synapse.events import FrozenEvent
 from synapse.events.utils import prune_event
@@ -190,11 +193,23 @@ def event_from_pdu_json(pdu_json, outlier=False):
         FrozenEvent
 
     Raises:
-        SynapseError: if the pdu is missing required fields
+        SynapseError: if the pdu is missing required fields or is otherwise
+            not a valid matrix event
     """
     # we could probably enforce a bunch of other fields here (room_id, sender,
     # origin, etc etc)
-    assert_params_in_request(pdu_json, ('event_id', 'type'))
+    assert_params_in_request(pdu_json, ('event_id', 'type', 'depth'))
+
+    depth = pdu_json['depth']
+    if not isinstance(depth, six.integer_types):
+        raise SynapseError(400, "Depth %r not an intger" % (depth, ),
+                           Codes.BAD_JSON)
+
+    if depth < 0:
+        raise SynapseError(400, "Depth too small", Codes.BAD_JSON)
+    elif depth > MAX_DEPTH:
+        raise SynapseError(400, "Depth too large", Codes.BAD_JSON)
+
     event = FrozenEvent(
         pdu_json
     )

synapse/federation/federation_client.py

@@ -19,6 +19,8 @@ import itertools
 import logging
 import random
 
+from six.moves import range
+
 from twisted.internet import defer
 
 from synapse.api.constants import Membership
@@ -33,7 +35,7 @@ from synapse.federation.federation_base import (
 import synapse.metrics
 from synapse.util import logcontext, unwrapFirstError
 from synapse.util.caches.expiringcache import ExpiringCache
-from synapse.util.logcontext import make_deferred_yieldable, preserve_fn
+from synapse.util.logcontext import make_deferred_yieldable, run_in_background
 from synapse.util.logutils import log_function
 from synapse.util.retryutils import NotRetryingDestination
 
@@ -413,11 +415,12 @@ class FederationClient(FederationBase):
 
         batch_size = 20
         missing_events = list(missing_events)
-        for i in xrange(0, len(missing_events), batch_size):
+        for i in range(0, len(missing_events), batch_size):
             batch = set(missing_events[i:i + batch_size])
 
             deferreds = [
-                preserve_fn(self.get_pdu)(
+                run_in_background(
+                    self.get_pdu,
                     destinations=random_server_list(),
                     event_id=e_id,
                 )

synapse/federation/transaction_queue.py

@@ -323,6 +323,8 @@ class TransactionQueue(object):
                     break
 
                 yield self._process_presence_inner(states_map.values())
+        except Exception:
+            logger.exception("Error sending presence states to servers")
         finally:
             self._processing_pending_presence = False
 

synapse/federation/transport/server.py

@@ -25,7 +25,7 @@ from synapse.http.servlet import (
 )
 from synapse.util.ratelimitutils import FederationRateLimiter
 from synapse.util.versionstring import get_version_string
-from synapse.util.logcontext import preserve_fn
+from synapse.util.logcontext import run_in_background
 from synapse.types import ThirdPartyInstanceID, get_domain_from_id
 
 import functools
@@ -152,11 +152,18 @@ class Authenticator(object):
         # alive
         retry_timings = yield self.store.get_destination_retry_timings(origin)
         if retry_timings and retry_timings["retry_last_ts"]:
-            logger.info("Marking origin %r as up", origin)
-            preserve_fn(self.store.set_destination_retry_timings)(origin, 0, 0)
+            run_in_background(self._reset_retry_timings, origin)
 
         defer.returnValue(origin)
 
+    @defer.inlineCallbacks
+    def _reset_retry_timings(self, origin):
+        try:
+            logger.info("Marking origin %r as up", origin)
+            yield self.store.set_destination_retry_timings(origin, 0, 0)
+        except Exception:
+            logger.exception("Error resetting retry timings on %s", origin)
+
 
 class BaseFederationServlet(object):
     REQUIRE_AUTH = True

synapse/federation/units.py

@@ -74,8 +74,6 @@ class Transaction(JsonEncodedObject):
         "previous_ids",
         "pdus",
         "edus",
-        "transaction_id",
-        "destination",
         "pdu_failures",
     ]
 

synapse/groups/attestations.py

@@ -42,7 +42,7 @@ from twisted.internet import defer
 
 from synapse.api.errors import SynapseError
 from synapse.types import get_domain_from_id
-from synapse.util.logcontext import preserve_fn
+from synapse.util.logcontext import run_in_background
 
 from signedjson.sign import sign_json
 
@@ -165,31 +165,35 @@ class GroupAttestionRenewer(object):
 
         @defer.inlineCallbacks
         def _renew_attestation(group_id, user_id):
-            if not self.is_mine_id(group_id):
-                destination = get_domain_from_id(group_id)
-            elif not self.is_mine_id(user_id):
-                destination = get_domain_from_id(user_id)
-            else:
-                logger.warn(
-                    "Incorrectly trying to do attestations for user: %r in %r",
-                    user_id, group_id,
+            try:
+                if not self.is_mine_id(group_id):
+                    destination = get_domain_from_id(group_id)
+                elif not self.is_mine_id(user_id):
+                    destination = get_domain_from_id(user_id)
+                else:
+                    logger.warn(
+                        "Incorrectly trying to do attestations for user: %r in %r",
+                        user_id, group_id,
+                    )
+                    yield self.store.remove_attestation_renewal(group_id, user_id)
+                    return
+
+                attestation = self.attestations.create_attestation(group_id, user_id)
+
+                yield self.transport_client.renew_group_attestation(
+                    destination, group_id, user_id,
+                    content={"attestation": attestation},
                 )
-                yield self.store.remove_attestation_renewal(group_id, user_id)
-                return
 
-            attestation = self.attestations.create_attestation(group_id, user_id)
-
-            yield self.transport_client.renew_group_attestation(
-                destination, group_id, user_id,
-                content={"attestation": attestation},
-            )
-
-            yield self.store.update_attestation_renewal(
-                group_id, user_id, attestation
-            )
+                yield self.store.update_attestation_renewal(
+                    group_id, user_id, attestation
+                )
+            except Exception:
+                logger.exception("Error renewing attestation of %r in %r",
+                                 user_id, group_id)
 
         for row in rows:
             group_id = row["group_id"]
             user_id = row["user_id"]
 
-            preserve_fn(_renew_attestation)(group_id, user_id)
+            run_in_background(_renew_attestation, group_id, user_id)

synapse/handlers/appservice.py

@@ -19,7 +19,7 @@ import synapse
 from synapse.api.constants import EventTypes
 from synapse.util.metrics import Measure
 from synapse.util.logcontext import (
-    make_deferred_yieldable, preserve_fn, run_in_background,
+    make_deferred_yieldable, run_in_background,
 )
 
 import logging
@@ -111,9 +111,7 @@ class ApplicationServicesHandler(object):
 
                         # Fork off pushes to these services
                         for service in services:
-                            preserve_fn(self.scheduler.submit_event_for_as)(
-                                service, event
-                            )
+                            self.scheduler.submit_event_for_as(service, event)
 
                     @defer.inlineCallbacks
                     def handle_room_events(events):
@@ -198,7 +196,10 @@ class ApplicationServicesHandler(object):
         services = yield self._get_services_for_3pn(protocol)
 
         results = yield make_deferred_yieldable(defer.DeferredList([
-            preserve_fn(self.appservice_api.query_3pe)(service, kind, protocol, fields)
+            run_in_background(
+                self.appservice_api.query_3pe,
+                service, kind, protocol, fields,
+            )
             for service in services
         ], consumeErrors=True))
 
@@ -259,11 +260,15 @@ class ApplicationServicesHandler(object):
             event based on the service regex.
         """
         services = self.store.get_app_services()
-        interested_list = [
-            s for s in services if (
-                yield s.is_interested(event, self.store)
-            )
-        ]
+
+        # we can't use a list comprehension here. Since python 3, list
+        # comprehensions use a generator internally. This means you can't yield
+        # inside of a list comprehension anymore.
+        interested_list = []
+        for s in services:
+            if (yield s.is_interested(event, self.store)):
+                interested_list.append(s)
+
         defer.returnValue(interested_list)
 
     def _get_services_for_user(self, user_id):

synapse/handlers/e2e_keys.py

@@ -24,7 +24,7 @@ from synapse.api.errors import (
     SynapseError, CodeMessageException, FederationDeniedError,
 )
 from synapse.types import get_domain_from_id, UserID
-from synapse.util.logcontext import preserve_fn, make_deferred_yieldable
+from synapse.util.logcontext import make_deferred_yieldable, run_in_background
 from synapse.util.retryutils import NotRetryingDestination
 
 logger = logging.getLogger(__name__)
@@ -139,9 +139,9 @@ class E2eKeysHandler(object):
                 failures[destination] = _exception_to_failure(e)
 
         yield make_deferred_yieldable(defer.gatherResults([
-            preserve_fn(do_remote_query)(destination)
+            run_in_background(do_remote_query, destination)
             for destination in remote_queries_not_in_cache
-        ]))
+        ], consumeErrors=True))
 
         defer.returnValue({
             "device_keys": results, "failures": failures,
@@ -242,9 +242,9 @@ class E2eKeysHandler(object):
                 failures[destination] = _exception_to_failure(e)
 
         yield make_deferred_yieldable(defer.gatherResults([
-            preserve_fn(claim_client_keys)(destination)
+            run_in_background(claim_client_keys, destination)
             for destination in remote_queries
-        ]))
+        ], consumeErrors=True))
 
         logger.info(
             "Claimed one-time-keys: %s",

synapse/handlers/federation.py

@@ -16,12 +16,14 @@
 
 """Contains handlers for federation events."""
 
-import httplib
 import itertools
 import logging
+import sys
 
 from signedjson.key import decode_verify_key_bytes
 from signedjson.sign import verify_signed_json
+import six
+from six.moves import http_client
 from twisted.internet import defer
 from unpaddedbase64 import decode_base64
 
@@ -637,7 +639,8 @@ class FederationHandler(BaseHandler):
 
                 results = yield logcontext.make_deferred_yieldable(defer.gatherResults(
                     [
-                        logcontext.preserve_fn(self.replication_layer.get_pdu)(
+                        logcontext.run_in_background(
+                            self.replication_layer.get_pdu,
                             [dest],
                             event_id,
                             outlier=True,
@@ -887,7 +890,7 @@ class FederationHandler(BaseHandler):
             logger.warn("Rejecting event %s which has %i prev_events",
                         ev.event_id, len(ev.prev_events))
             raise SynapseError(
-                httplib.BAD_REQUEST,
+                http_client.BAD_REQUEST,
                 "Too many prev_events",
             )
 
@@ -895,7 +898,7 @@ class FederationHandler(BaseHandler):
             logger.warn("Rejecting event %s which has %i auth_events",
                         ev.event_id, len(ev.auth_events))
             raise SynapseError(
-                httplib.BAD_REQUEST,
+                http_client.BAD_REQUEST,
                 "Too many auth_events",
             )
 
@@ -1023,7 +1026,7 @@ class FederationHandler(BaseHandler):
             # lots of requests for missing prev_events which we do actually
             # have. Hence we fire off the deferred, but don't wait for it.
 
-            logcontext.preserve_fn(self._handle_queued_pdus)(room_queue)
+            logcontext.run_in_background(self._handle_queued_pdus, room_queue)
 
         defer.returnValue(True)
 
@@ -1513,18 +1516,21 @@ class FederationHandler(BaseHandler):
                 backfilled=backfilled,
             )
         except:  # noqa: E722, as we reraise the exception this is fine.
-            # Ensure that we actually remove the entries in the push actions
-            # staging area
-            logcontext.preserve_fn(
-                self.store.remove_push_actions_from_staging
-            )(event.event_id)
-            raise
+            tp, value, tb = sys.exc_info()
+
+            logcontext.run_in_background(
+                self.store.remove_push_actions_from_staging,
+                event.event_id,
+            )
+
+            six.reraise(tp, value, tb)
 
         if not backfilled:
             # this intentionally does not yield: we don't care about the result
             # and don't need to wait for it.
-            logcontext.preserve_fn(self.pusher_pool.on_new_notifications)(
-                event_stream_id, max_stream_id
+            logcontext.run_in_background(
+                self.pusher_pool.on_new_notifications,
+                event_stream_id, max_stream_id,
             )
 
         defer.returnValue((context, event_stream_id, max_stream_id))
@@ -1538,7 +1544,8 @@ class FederationHandler(BaseHandler):
         """
         contexts = yield logcontext.make_deferred_yieldable(defer.gatherResults(
             [
-                logcontext.preserve_fn(self._prep_event)(
+                logcontext.run_in_background(
+                    self._prep_event,
                     origin,
                     ev_info["event"],
                     state=ev_info.get("state"),
@@ -1867,7 +1874,8 @@ class FederationHandler(BaseHandler):
 
             different_events = yield logcontext.make_deferred_yieldable(
                 defer.gatherResults([
-                    logcontext.preserve_fn(self.store.get_event)(
+                    logcontext.run_in_background(
+                        self.store.get_event,
                         d,
                         allow_none=True,
                         allow_rejected=False,

synapse/handlers/initial_sync.py

@@ -27,7 +27,7 @@ from synapse.types import (
 from synapse.util import unwrapFirstError
 from synapse.util.async import concurrently_execute
 from synapse.util.caches.snapshot_cache import SnapshotCache
-from synapse.util.logcontext import make_deferred_yieldable, preserve_fn
+from synapse.util.logcontext import make_deferred_yieldable, run_in_background
 from synapse.visibility import filter_events_for_client
 
 from ._base import BaseHandler
@@ -166,7 +166,8 @@ class InitialSyncHandler(BaseHandler):
                 (messages, token), current_state = yield make_deferred_yieldable(
                     defer.gatherResults(
                         [
-                            preserve_fn(self.store.get_recent_events_for_room)(
+                            run_in_background(
+                                self.store.get_recent_events_for_room,
                                 event.room_id,
                                 limit=limit,
                                 end_token=room_end_token,
@@ -180,8 +181,8 @@ class InitialSyncHandler(BaseHandler):
                     self.store, user_id, messages
                 )
 
-                start_token = now_token.copy_and_replace("room_key", token[0])
-                end_token = now_token.copy_and_replace("room_key", token[1])
+                start_token = now_token.copy_and_replace("room_key", token)
+                end_token = now_token.copy_and_replace("room_key", room_end_token)
                 time_now = self.clock.time_msec()
 
                 d["messages"] = {
@@ -324,8 +325,8 @@ class InitialSyncHandler(BaseHandler):
             self.store, user_id, messages, is_peeking=is_peeking
         )
 
-        start_token = StreamToken.START.copy_and_replace("room_key", token[0])
-        end_token = StreamToken.START.copy_and_replace("room_key", token[1])
+        start_token = StreamToken.START.copy_and_replace("room_key", token)
+        end_token = StreamToken.START.copy_and_replace("room_key", stream_token)
 
         time_now = self.clock.time_msec()
 
@@ -391,9 +392,10 @@ class InitialSyncHandler(BaseHandler):
 
         presence, receipts, (messages, token) = yield defer.gatherResults(
             [
-                preserve_fn(get_presence)(),
-                preserve_fn(get_receipts)(),
-                preserve_fn(self.store.get_recent_events_for_room)(
+                run_in_background(get_presence),
+                run_in_background(get_receipts),
+                run_in_background(
+                    self.store.get_recent_events_for_room,
                     room_id,
                     limit=limit,
                     end_token=now_token.room_key,
@@ -406,8 +408,8 @@ class InitialSyncHandler(BaseHandler):
             self.store, user_id, messages, is_peeking=is_peeking,
         )
 
-        start_token = now_token.copy_and_replace("room_key", token[0])
-        end_token = now_token.copy_and_replace("room_key", token[1])
+        start_token = now_token.copy_and_replace("room_key", token)
+        end_token = now_token
 
         time_now = self.clock.time_msec()
 

synapse/handlers/message.py

@@ -13,10 +13,16 @@
 # 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
+import simplejson
+import sys
+
+from canonicaljson import encode_canonical_json
+import six
 from twisted.internet import defer, reactor
 from twisted.python.failure import Failure
 
-from synapse.api.constants import EventTypes, Membership
+from synapse.api.constants import EventTypes, Membership, MAX_DEPTH
 from synapse.api.errors import AuthError, Codes, SynapseError
 from synapse.crypto.event_signing import add_hashes_and_signatures
 from synapse.events.utils import serialize_event
@@ -25,7 +31,7 @@ from synapse.types import (
     UserID, RoomAlias, RoomStreamToken,
 )
 from synapse.util.async import run_on_reactor, ReadWriteLock, Limiter
-from synapse.util.logcontext import preserve_fn, run_in_background
+from synapse.util.logcontext import run_in_background
 from synapse.util.metrics import measure_func
 from synapse.util.frozenutils import frozendict_json_encoder
 from synapse.util.stringutils import random_string
@@ -34,11 +40,6 @@ from synapse.replication.http.send_event import send_event_to_master
 
 from ._base import BaseHandler
 
-from canonicaljson import encode_canonical_json
-
-import logging
-import simplejson
-
 logger = logging.getLogger(__name__)
 
 
@@ -624,6 +625,10 @@ class EventCreationHandler(object):
 
         if prev_events_and_hashes:
             depth = max([d for _, _, d in prev_events_and_hashes]) + 1
+            # we cap depth of generated events, to ensure that they are not
+            # rejected by other servers (and so that they can be persisted in
+            # the db)
+            depth = min(depth, MAX_DEPTH)
         else:
             depth = 1
 
@@ -729,8 +734,14 @@ class EventCreationHandler(object):
         except:  # noqa: E722, as we reraise the exception this is fine.
             # Ensure that we actually remove the entries in the push actions
             # staging area, if we calculated them.
-            preserve_fn(self.store.remove_push_actions_from_staging)(event.event_id)
-            raise
+            tp, value, tb = sys.exc_info()
+
+            run_in_background(
+                self.store.remove_push_actions_from_staging,
+                event.event_id,
+            )
+
+            six.reraise(tp, value, tb)
 
     @defer.inlineCallbacks
     def persist_and_notify_client_event(
@@ -850,22 +861,33 @@ class EventCreationHandler(object):
 
         # this intentionally does not yield: we don't care about the result
         # and don't need to wait for it.
-        preserve_fn(self.pusher_pool.on_new_notifications)(
+        run_in_background(
+            self.pusher_pool.on_new_notifications,
             event_stream_id, max_stream_id
         )
 
         @defer.inlineCallbacks
         def _notify():
             yield run_on_reactor()
-            self.notifier.on_new_room_event(
-                event, event_stream_id, max_stream_id,
-                extra_users=extra_users
-            )
+            try:
+                self.notifier.on_new_room_event(
+                    event, event_stream_id, max_stream_id,
+                    extra_users=extra_users
+                )
+            except Exception:
+                logger.exception("Error notifying about new room event")
 
-        preserve_fn(_notify)()
+        run_in_background(_notify)
 
         if event.type == EventTypes.Message:
-            presence = self.hs.get_presence_handler()
             # We don't want to block sending messages on any presence code. This
             # matters as sometimes presence code can take a while.
-            preserve_fn(presence.bump_presence_active_time)(requester.user)
+            run_in_background(self._bump_active_time, requester.user)
+
+    @defer.inlineCallbacks
+    def _bump_active_time(self, user):
+        try:
+            presence = self.hs.get_presence_handler()
+            yield presence.bump_presence_active_time(user)
+        except Exception:
+            logger.exception("Error bumping presence active time")

synapse/handlers/presence.py

@@ -31,7 +31,7 @@ from synapse.storage.presence import UserPresenceState
 
 from synapse.util.caches.descriptors import cachedInlineCallbacks
 from synapse.util.async import Linearizer
-from synapse.util.logcontext import preserve_fn
+from synapse.util.logcontext import run_in_background
 from synapse.util.logutils import log_function
 from synapse.util.metrics import Measure
 from synapse.util.wheel_timer import WheelTimer
@@ -254,6 +254,14 @@ class PresenceHandler(object):
 
         logger.info("Finished _persist_unpersisted_changes")
 
+    @defer.inlineCallbacks
+    def _update_states_and_catch_exception(self, new_states):
+        try:
+            res = yield self._update_states(new_states)
+            defer.returnValue(res)
+        except Exception:
+            logger.exception("Error updating presence")
+
     @defer.inlineCallbacks
     def _update_states(self, new_states):
         """Updates presence of users. Sets the appropriate timeouts. Pokes
@@ -364,7 +372,7 @@ class PresenceHandler(object):
                     now=now,
                 )
 
-            preserve_fn(self._update_states)(changes)
+            run_in_background(self._update_states_and_catch_exception, changes)
         except Exception:
             logger.exception("Exception in _handle_timeouts loop")
 
@@ -422,20 +430,23 @@ class PresenceHandler(object):
 
         @defer.inlineCallbacks
         def _end():
-            if affect_presence:
+            try:
                 self.user_to_num_current_syncs[user_id] -= 1
 
                 prev_state = yield self.current_state_for_user(user_id)
                 yield self._update_states([prev_state.copy_and_replace(
                     last_user_sync_ts=self.clock.time_msec(),
                 )])
+            except Exception:
+                logger.exception("Error updating presence after sync")
 
         @contextmanager
         def _user_syncing():
             try:
                 yield
             finally:
-                preserve_fn(_end)()
+                if affect_presence:
+                    run_in_background(_end)
 
         defer.returnValue(_user_syncing())
 

synapse/handlers/receipts.py

@@ -135,37 +135,40 @@ class ReceiptsHandler(BaseHandler):
         """Given a list of receipts, works out which remote servers should be
         poked and pokes them.
         """
-        # TODO: Some of this stuff should be coallesced.
-        for receipt in receipts:
-            room_id = receipt["room_id"]
-            receipt_type = receipt["receipt_type"]
-            user_id = receipt["user_id"]
-            event_ids = receipt["event_ids"]
-            data = receipt["data"]
+        try:
+            # TODO: Some of this stuff should be coallesced.
+            for receipt in receipts:
+                room_id = receipt["room_id"]
+                receipt_type = receipt["receipt_type"]
+                user_id = receipt["user_id"]
+                event_ids = receipt["event_ids"]
+                data = receipt["data"]
 
-            users = yield self.state.get_current_user_in_room(room_id)
-            remotedomains = set(get_domain_from_id(u) for u in users)
-            remotedomains = remotedomains.copy()
-            remotedomains.discard(self.server_name)
+                users = yield self.state.get_current_user_in_room(room_id)
+                remotedomains = set(get_domain_from_id(u) for u in users)
+                remotedomains = remotedomains.copy()
+                remotedomains.discard(self.server_name)
 
-            logger.debug("Sending receipt to: %r", remotedomains)
+                logger.debug("Sending receipt to: %r", remotedomains)
 
-            for domain in remotedomains:
-                self.federation.send_edu(
-                    destination=domain,
-                    edu_type="m.receipt",
-                    content={
-                        room_id: {
-                            receipt_type: {
-                                user_id: {
-                                    "event_ids": event_ids,
-                                    "data": data,
+                for domain in remotedomains:
+                    self.federation.send_edu(
+                        destination=domain,
+                        edu_type="m.receipt",
+                        content={
+                            room_id: {
+                                receipt_type: {
+                                    user_id: {
+                                        "event_ids": event_ids,
+                                        "data": data,
+                                    }
                                 }
-                            }
+                            },
                         },
-                    },
-                    key=(room_id, receipt_type, user_id),
-                )
+                        key=(room_id, receipt_type, user_id),
+                    )
+        except Exception:
+            logger.exception("Error pushing receipts to remote servers")
 
     @defer.inlineCallbacks
     def get_receipts_for_room(self, room_id, to_key):

synapse/handlers/room_list.py

@@ -15,6 +15,8 @@
 
 from twisted.internet import defer
 
+from six.moves import range
+
 from ._base import BaseHandler
 
 from synapse.api.constants import (
@@ -200,7 +202,7 @@ class RoomListHandler(BaseHandler):
             step = len(rooms_to_scan) if len(rooms_to_scan) != 0 else 1
 
         chunk = []
-        for i in xrange(0, len(rooms_to_scan), step):
+        for i in range(0, len(rooms_to_scan), step):
             batch = rooms_to_scan[i:i + step]
             logger.info("Processing %i rooms for result", len(batch))
             yield concurrently_execute(

synapse/handlers/sync.py

@@ -354,12 +354,24 @@ class SyncHandler(object):
                 since_key = since_token.room_key
 
             while limited and len(recents) < timeline_limit and max_repeat:
-                events, end_key = yield self.store.get_room_events_stream_for_room(
-                    room_id,
-                    limit=load_limit + 1,
-                    from_key=since_key,
-                    to_key=end_key,
-                )
+                # If we have a since_key then we are trying to get any events
+                # that have happened since `since_key` up to `end_key`, so we
+                # can just use `get_room_events_stream_for_room`.
+                # Otherwise, we want to return the last N events in the room
+                # in toplogical ordering.
+                if since_key:
+                    events, end_key = yield self.store.get_room_events_stream_for_room(
+                        room_id,
+                        limit=load_limit + 1,
+                        from_key=since_key,
+                        to_key=end_key,
+                    )
+                else:
+                    events, end_key = yield self.store.get_recent_events_for_room(
+                        room_id,
+                        limit=load_limit + 1,
+                        end_token=end_key,
+                    )
                 loaded_recents = sync_config.filter_collection.filter_room_timeline(
                     events
                 )
@@ -429,7 +441,7 @@ class SyncHandler(object):
         Returns:
             A Deferred map from ((type, state_key)->Event)
         """
-        last_events, token = yield self.store.get_recent_events_for_room(
+        last_events, _ = yield self.store.get_recent_events_for_room(
             room_id, end_token=stream_position.room_key, limit=1,
         )
 

synapse/handlers/typing.py

@@ -16,7 +16,7 @@
 from twisted.internet import defer
 
 from synapse.api.errors import SynapseError, AuthError
-from synapse.util.logcontext import preserve_fn
+from synapse.util.logcontext import run_in_background
 from synapse.util.metrics import Measure
 from synapse.util.wheel_timer import WheelTimer
 from synapse.types import UserID, get_domain_from_id
@@ -97,7 +97,8 @@ class TypingHandler(object):
             if self.hs.is_mine_id(member.user_id):
                 last_fed_poke = self._member_last_federation_poke.get(member, None)
                 if not last_fed_poke or last_fed_poke + FEDERATION_PING_INTERVAL <= now:
-                    preserve_fn(self._push_remote)(
+                    run_in_background(
+                        self._push_remote,
                         member=member,
                         typing=True
                     )
@@ -196,7 +197,7 @@ class TypingHandler(object):
     def _push_update(self, member, typing):
         if self.hs.is_mine_id(member.user_id):
             # Only send updates for changes to our own users.
-            preserve_fn(self._push_remote)(member, typing)
+            run_in_background(self._push_remote, member, typing)
 
         self._push_update_local(
             member=member,
@@ -205,28 +206,31 @@ class TypingHandler(object):
 
     @defer.inlineCallbacks
     def _push_remote(self, member, typing):
-        users = yield self.state.get_current_user_in_room(member.room_id)
-        self._member_last_federation_poke[member] = self.clock.time_msec()
+        try:
+            users = yield self.state.get_current_user_in_room(member.room_id)
+            self._member_last_federation_poke[member] = self.clock.time_msec()
 
-        now = self.clock.time_msec()
-        self.wheel_timer.insert(
-            now=now,
-            obj=member,
-            then=now + FEDERATION_PING_INTERVAL,
-        )
+            now = self.clock.time_msec()
+            self.wheel_timer.insert(
+                now=now,
+                obj=member,
+                then=now + FEDERATION_PING_INTERVAL,
+            )
 
-        for domain in set(get_domain_from_id(u) for u in users):
-            if domain != self.server_name:
-                self.federation.send_edu(
-                    destination=domain,
-                    edu_type="m.typing",
-                    content={
-                        "room_id": member.room_id,
-                        "user_id": member.user_id,
-                        "typing": typing,
-                    },
-                    key=member,
-                )
+            for domain in set(get_domain_from_id(u) for u in users):
+                if domain != self.server_name:
+                    self.federation.send_edu(
+                        destination=domain,
+                        edu_type="m.typing",
+                        content={
+                            "room_id": member.room_id,
+                            "user_id": member.user_id,
+                            "typing": typing,
+                        },
+                        key=member,
+                    )
+        except Exception:
+            logger.exception("Error pushing typing notif to remotes")
 
     @defer.inlineCallbacks
     def _recv_edu(self, origin, content):

synapse/http/__init__.py

@@ -1,5 +1,6 @@
 # -*- coding: utf-8 -*-
 # Copyright 2014-2016 OpenMarket Ltd
+# Copyright 2018 New Vector Ltd
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -12,3 +13,24 @@
 # 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.
+from twisted.internet.defer import CancelledError
+from twisted.python import failure
+
+from synapse.api.errors import SynapseError
+
+
+class RequestTimedOutError(SynapseError):
+    """Exception representing timeout of an outbound request"""
+    def __init__(self):
+        super(RequestTimedOutError, self).__init__(504, "Timed out")
+
+
+def cancelled_to_request_timed_out_error(value, timeout):
+    """Turns CancelledErrors into RequestTimedOutErrors.
+
+    For use with async.add_timeout_to_deferred
+    """
+    if isinstance(value, failure.Failure):
+        value.trap(CancelledError)
+        raise RequestTimedOutError()
+    return value

synapse/http/additional_resource.py

@@ -13,7 +13,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from synapse.http.server import wrap_request_handler
+from synapse.http.server import wrap_json_request_handler
 from twisted.web.resource import Resource
 from twisted.web.server import NOT_DONE_YET
 
@@ -42,14 +42,13 @@ class AdditionalResource(Resource):
         Resource.__init__(self)
         self._handler = handler
 
-        # these are required by the request_handler wrapper
-        self.version_string = hs.version_string
+        # required by the request_handler wrapper
         self.clock = hs.get_clock()
 
     def render(self, request):
         self._async_render(request)
         return NOT_DONE_YET
 
-    @wrap_request_handler
+    @wrap_json_request_handler
     def _async_render(self, request):
         return self._handler(request)

synapse/http/client.py

@@ -1,5 +1,6 @@
 # -*- coding: utf-8 -*-
 # Copyright 2014-2016 OpenMarket Ltd
+# Copyright 2018 New Vector Ltd
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -18,9 +19,10 @@ from OpenSSL.SSL import VERIFY_NONE
 from synapse.api.errors import (
     CodeMessageException, MatrixCodeMessageException, SynapseError, Codes,
 )
+from synapse.http import cancelled_to_request_timed_out_error
+from synapse.util.async import add_timeout_to_deferred
 from synapse.util.caches import CACHE_SIZE_FACTOR
 from synapse.util.logcontext import make_deferred_yieldable
-from synapse.util import logcontext
 import synapse.metrics
 from synapse.http.endpoint import SpiderEndpoint
 
@@ -38,7 +40,7 @@ from twisted.web.http import PotentialDataLoss
 from twisted.web.http_headers import Headers
 from twisted.web._newclient import ResponseDone
 
-from StringIO import StringIO
+from six import StringIO
 
 import simplejson as json
 import logging
@@ -95,21 +97,17 @@ class SimpleHttpClient(object):
         # counters to it
         outgoing_requests_counter.inc(method)
 
-        def send_request():
-            request_deferred = self.agent.request(
-                method, uri, *args, **kwargs
-            )
-
-            return self.clock.time_bound_deferred(
-                request_deferred,
-                time_out=60,
-            )
-
         logger.info("Sending request %s %s", method, uri)
 
         try:
-            with logcontext.PreserveLoggingContext():
-                response = yield send_request()
+            request_deferred = self.agent.request(
+                method, uri, *args, **kwargs
+            )
+            add_timeout_to_deferred(
+                request_deferred,
+                60, cancelled_to_request_timed_out_error,
+            )
+            response = yield make_deferred_yieldable(request_deferred)
 
             incoming_responses_counter.inc(method, response.code)
             logger.info(
@@ -509,7 +507,7 @@ class SpiderHttpClient(SimpleHttpClient):
                     reactor,
                     SpiderEndpointFactory(hs)
                 )
-            ), [('gzip', GzipDecoder)]
+            ), [(b'gzip', GzipDecoder)]
         )
         # We could look like Chrome:
         # self.user_agent = ("Mozilla/5.0 (%s) (KHTML, like Gecko)

synapse/http/endpoint.py

@@ -115,10 +115,15 @@ class _WrappedConnection(object):
         if time.time() - self.last_request >= 2.5 * 60:
             self.abort()
             # Abort the underlying TLS connection. The abort() method calls
-            # loseConnection() on the underlying TLS connection which tries to
+            # loseConnection() on the TLS connection which tries to
             # shutdown the connection cleanly. We call abortConnection()
-            # since that will promptly close the underlying TCP connection.
-            self.transport.abortConnection()
+            # since that will promptly close the TLS connection.
+            #
+            # In Twisted >18.4; the TLS connection will be None if it has closed
+            # which will make abortConnection() throw. Check that the TLS connection
+            # is not None before trying to close it.
+            if self.transport.getHandle() is not None:
+                self.transport.abortConnection()
 
     def request(self, request):
         self.last_request = time.time()
@@ -286,7 +291,7 @@ def resolve_service(service_name, dns_client=client, cache=SERVER_CACHE, clock=t
         if (len(answers) == 1
                 and answers[0].type == dns.SRV
                 and answers[0].payload
-                and answers[0].payload.target == dns.Name('.')):
+                and answers[0].payload.target == dns.Name(b'.')):
             raise ConnectError("Service %s unavailable" % service_name)
 
         for answer in answers:

synapse/http/matrixfederationclient.py

@@ -1,5 +1,6 @@
 # -*- coding: utf-8 -*-
 # Copyright 2014-2016 OpenMarket Ltd
+# Copyright 2018 New Vector Ltd
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -12,17 +13,19 @@
 # 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 synapse.util.retryutils
 from twisted.internet import defer, reactor, protocol
 from twisted.internet.error import DNSLookupError
 from twisted.web.client import readBody, HTTPConnectionPool, Agent
 from twisted.web.http_headers import Headers
 from twisted.web._newclient import ResponseDone
 
+from synapse.http import cancelled_to_request_timed_out_error
 from synapse.http.endpoint import matrix_federation_endpoint
-from synapse.util.async import sleep
-from synapse.util import logcontext
 import synapse.metrics
+from synapse.util.async import sleep, add_timeout_to_deferred
+from synapse.util import logcontext
+from synapse.util.logcontext import make_deferred_yieldable
+import synapse.util.retryutils
 
 from canonicaljson import encode_canonical_json
 
@@ -38,8 +41,7 @@ import logging
 import random
 import sys
 import urllib
-import urlparse
-
+from six.moves.urllib import parse as urlparse
 
 logger = logging.getLogger(__name__)
 outbound_logger = logging.getLogger("synapse.http.outbound")
@@ -184,21 +186,20 @@ class MatrixFederationHttpClient(object):
                         producer = body_callback(method, http_url_bytes, headers_dict)
 
                     try:
-                        def send_request():
-                            request_deferred = self.agent.request(
-                                method,
-                                url_bytes,
-                                Headers(headers_dict),
-                                producer
-                            )
-
-                            return self.clock.time_bound_deferred(
-                                request_deferred,
-                                time_out=timeout / 1000. if timeout else 60,
-                            )
-
-                        with logcontext.PreserveLoggingContext():
-                            response = yield send_request()
+                        request_deferred = self.agent.request(
+                            method,
+                            url_bytes,
+                            Headers(headers_dict),
+                            producer
+                        )
+                        add_timeout_to_deferred(
+                            request_deferred,
+                            timeout / 1000. if timeout else 60,
+                            cancelled_to_request_timed_out_error,
+                        )
+                        response = yield make_deferred_yieldable(
+                            request_deferred,
+                        )
 
                         log_result = "%d %s" % (response.code, response.phrase,)
                         break

synapse/http/request_metrics.py

@@ -0,0 +1,149 @@
+# -*- coding: utf-8 -*-
+# Copyright 2014-2016 OpenMarket Ltd
+# Copyright 2018 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# 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
+
+import synapse.metrics
+from synapse.util.logcontext import LoggingContext
+
+logger = logging.getLogger(__name__)
+
+metrics = synapse.metrics.get_metrics_for("synapse.http.server")
+
+# total number of responses served, split by method/servlet/tag
+response_count = metrics.register_counter(
+    "response_count",
+    labels=["method", "servlet", "tag"],
+    alternative_names=(
+        # the following are all deprecated aliases for the same metric
+        metrics.name_prefix + x for x in (
+            "_requests",
+            "_response_time:count",
+            "_response_ru_utime:count",
+            "_response_ru_stime:count",
+            "_response_db_txn_count:count",
+            "_response_db_txn_duration:count",
+        )
+    )
+)
+
+requests_counter = metrics.register_counter(
+    "requests_received",
+    labels=["method", "servlet", ],
+)
+
+outgoing_responses_counter = metrics.register_counter(
+    "responses",
+    labels=["method", "code"],
+)
+
+response_timer = metrics.register_counter(
+    "response_time_seconds",
+    labels=["method", "servlet", "tag"],
+    alternative_names=(
+        metrics.name_prefix + "_response_time:total",
+    ),
+)
+
+response_ru_utime = metrics.register_counter(
+    "response_ru_utime_seconds", labels=["method", "servlet", "tag"],
+    alternative_names=(
+        metrics.name_prefix + "_response_ru_utime:total",
+    ),
+)
+
+response_ru_stime = metrics.register_counter(
+    "response_ru_stime_seconds", labels=["method", "servlet", "tag"],
+    alternative_names=(
+        metrics.name_prefix + "_response_ru_stime:total",
+    ),
+)
+
+response_db_txn_count = metrics.register_counter(
+    "response_db_txn_count", labels=["method", "servlet", "tag"],
+    alternative_names=(
+        metrics.name_prefix + "_response_db_txn_count:total",
+    ),
+)
+
+# seconds spent waiting for db txns, excluding scheduling time, when processing
+# this request
+response_db_txn_duration = metrics.register_counter(
+    "response_db_txn_duration_seconds", labels=["method", "servlet", "tag"],
+    alternative_names=(
+        metrics.name_prefix + "_response_db_txn_duration:total",
+    ),
+)
+
+# seconds spent waiting for a db connection, when processing this request
+response_db_sched_duration = metrics.register_counter(
+    "response_db_sched_duration_seconds", labels=["method", "servlet", "tag"]
+)
+
+# size in bytes of the response written
+response_size = metrics.register_counter(
+    "response_size", labels=["method", "servlet", "tag"]
+)
+
+
+class RequestMetrics(object):
+    def start(self, time_msec, name):
+        self.start = time_msec
+        self.start_context = LoggingContext.current_context()
+        self.name = name
+
+    def stop(self, time_msec, request):
+        context = LoggingContext.current_context()
+
+        tag = ""
+        if context:
+            tag = context.tag
+
+            if context != self.start_context:
+                logger.warn(
+                    "Context have unexpectedly changed %r, %r",
+                    context, self.start_context
+                )
+                return
+
+        outgoing_responses_counter.inc(request.method, str(request.code))
+
+        response_count.inc(request.method, self.name, tag)
+
+        response_timer.inc_by(
+            time_msec - self.start, request.method,
+            self.name, tag
+        )
+
+        ru_utime, ru_stime = context.get_resource_usage()
+
+        response_ru_utime.inc_by(
+            ru_utime, request.method, self.name, tag
+        )
+        response_ru_stime.inc_by(
+            ru_stime, request.method, self.name, tag
+        )
+        response_db_txn_count.inc_by(
+            context.db_txn_count, request.method, self.name, tag
+        )
+        response_db_txn_duration.inc_by(
+            context.db_txn_duration_ms / 1000., request.method, self.name, tag
+        )
+        response_db_sched_duration.inc_by(
+            context.db_sched_duration_ms / 1000., request.method, self.name, tag
+        )
+
+        response_size.inc_by(request.sentLength, request.method, self.name, tag)

synapse/http/server.py

@@ -18,6 +18,9 @@
 from synapse.api.errors import (
     cs_exception, SynapseError, CodeMessageException, UnrecognizedRequestError, Codes
 )
+from synapse.http.request_metrics import (
+    requests_counter,
+)
 from synapse.util.logcontext import LoggingContext, PreserveLoggingContext
 from synapse.util.caches import intern_dict
 from synapse.util.metrics import Measure
@@ -41,178 +44,103 @@ import simplejson
 
 logger = logging.getLogger(__name__)
 
-metrics = synapse.metrics.get_metrics_for(__name__)
 
-# total number of responses served, split by method/servlet/tag
-response_count = metrics.register_counter(
-    "response_count",
-    labels=["method", "servlet", "tag"],
-    alternative_names=(
-        # the following are all deprecated aliases for the same metric
-        metrics.name_prefix + x for x in (
-            "_requests",
-            "_response_time:count",
-            "_response_ru_utime:count",
-            "_response_ru_stime:count",
-            "_response_db_txn_count:count",
-            "_response_db_txn_duration:count",
-        )
-    )
-)
+def wrap_json_request_handler(h):
+    """Wraps a request handler method with exception handling.
 
-requests_counter = metrics.register_counter(
-    "requests_received",
-    labels=["method", "servlet", ],
-)
+    Also adds logging as per wrap_request_handler_with_logging.
 
-outgoing_responses_counter = metrics.register_counter(
-    "responses",
-    labels=["method", "code"],
-)
+    The handler method must have a signature of "handle_foo(self, request)",
+    where "self" must have a "clock" attribute (and "request" must be a
+    SynapseRequest).
 
-response_timer = metrics.register_counter(
-    "response_time_seconds",
-    labels=["method", "servlet", "tag"],
-    alternative_names=(
-        metrics.name_prefix + "_response_time:total",
-    ),
-)
-
-response_ru_utime = metrics.register_counter(
-    "response_ru_utime_seconds", labels=["method", "servlet", "tag"],
-    alternative_names=(
-        metrics.name_prefix + "_response_ru_utime:total",
-    ),
-)
-
-response_ru_stime = metrics.register_counter(
-    "response_ru_stime_seconds", labels=["method", "servlet", "tag"],
-    alternative_names=(
-        metrics.name_prefix + "_response_ru_stime:total",
-    ),
-)
-
-response_db_txn_count = metrics.register_counter(
-    "response_db_txn_count", labels=["method", "servlet", "tag"],
-    alternative_names=(
-        metrics.name_prefix + "_response_db_txn_count:total",
-    ),
-)
-
-# seconds spent waiting for db txns, excluding scheduling time, when processing
-# this request
-response_db_txn_duration = metrics.register_counter(
-    "response_db_txn_duration_seconds", labels=["method", "servlet", "tag"],
-    alternative_names=(
-        metrics.name_prefix + "_response_db_txn_duration:total",
-    ),
-)
-
-# seconds spent waiting for a db connection, when processing this request
-response_db_sched_duration = metrics.register_counter(
-    "response_db_sched_duration_seconds", labels=["method", "servlet", "tag"]
-)
-
-# size in bytes of the response written
-response_size = metrics.register_counter(
-    "response_size", labels=["method", "servlet", "tag"]
-)
-
-_next_request_id = 0
-
-
-def request_handler(include_metrics=False):
-    """Decorator for ``wrap_request_handler``"""
-    return lambda request_handler: wrap_request_handler(request_handler, include_metrics)
-
-
-def wrap_request_handler(request_handler, include_metrics=False):
-    """Wraps a method that acts as a request handler with the necessary logging
-    and exception handling.
-
-    The method must have a signature of "handle_foo(self, request)". The
-    argument "self" must have "version_string" and "clock" attributes. The
-    argument "request" must be a twisted HTTP request.
-
-    The method must return a deferred. If the deferred succeeds we assume that
+    The handler must return a deferred. If the deferred succeeds we assume that
     a response has been sent. If the deferred fails with a SynapseError we use
     it to send a JSON response with the appropriate HTTP reponse code. If the
     deferred fails with any other type of error we send a 500 reponse.
-
-    We insert a unique request-id into the logging context for this request and
-    log the response and duration for this request.
     """
 
     @defer.inlineCallbacks
     def wrapped_request_handler(self, request):
-        global _next_request_id
-        request_id = "%s-%s" % (request.method, _next_request_id)
-        _next_request_id += 1
+        try:
+            yield h(self, request)
+        except CodeMessageException as e:
+            code = e.code
+            if isinstance(e, SynapseError):
+                logger.info(
+                    "%s SynapseError: %s - %s", request, code, e.msg
+                )
+            else:
+                logger.exception(e)
+            respond_with_json(
+                request, code, cs_exception(e), send_cors=True,
+                pretty_print=_request_user_agent_is_curl(request),
+            )
 
+        except Exception:
+            # failure.Failure() fishes the original Failure out
+            # of our stack, and thus gives us a sensible stack
+            # trace.
+            f = failure.Failure()
+            logger.error(
+                "Failed handle request via %r: %r: %s",
+                h,
+                request,
+                f.getTraceback().rstrip(),
+            )
+            respond_with_json(
+                request,
+                500,
+                {
+                    "error": "Internal server error",
+                    "errcode": Codes.UNKNOWN,
+                },
+                send_cors=True,
+                pretty_print=_request_user_agent_is_curl(request),
+            )
+
+    return wrap_request_handler_with_logging(wrapped_request_handler)
+
+
+def wrap_request_handler_with_logging(h):
+    """Wraps a request handler to provide logging and metrics
+
+    The handler method must have a signature of "handle_foo(self, request)",
+    where "self" must have a "clock" attribute (and "request" must be a
+    SynapseRequest).
+
+    As well as calling `request.processing` (which will log the response and
+    duration for this request), the wrapped request handler will insert the
+    request id into the logging context.
+    """
+    @defer.inlineCallbacks
+    def wrapped_request_handler(self, request):
+        """
+        Args:
+            self:
+            request (synapse.http.site.SynapseRequest):
+        """
+
+        request_id = request.get_request_id()
         with LoggingContext(request_id) as request_context:
+            request_context.request = request_id
             with Measure(self.clock, "wrapped_request_handler"):
-                request_metrics = RequestMetrics()
                 # we start the request metrics timer here with an initial stab
                 # at the servlet name. For most requests that name will be
                 # JsonResource (or a subclass), and JsonResource._async_render
                 # will update it once it picks a servlet.
                 servlet_name = self.__class__.__name__
-                request_metrics.start(self.clock, name=servlet_name)
+                with request.processing(servlet_name):
+                    with PreserveLoggingContext(request_context):
+                        d = h(self, request)
 
-                request_context.request = request_id
-                with request.processing():
-                    try:
-                        with PreserveLoggingContext(request_context):
-                            if include_metrics:
-                                yield request_handler(self, request, request_metrics)
-                            else:
-                                requests_counter.inc(request.method, servlet_name)
-                                yield request_handler(self, request)
-                    except CodeMessageException as e:
-                        code = e.code
-                        if isinstance(e, SynapseError):
-                            logger.info(
-                                "%s SynapseError: %s - %s", request, code, e.msg
-                            )
-                        else:
-                            logger.exception(e)
-                        outgoing_responses_counter.inc(request.method, str(code))
-                        respond_with_json(
-                            request, code, cs_exception(e), send_cors=True,
-                            pretty_print=_request_user_agent_is_curl(request),
-                            version_string=self.version_string,
-                        )
-                    except Exception:
-                        # failure.Failure() fishes the original Failure out
-                        # of our stack, and thus gives us a sensible stack
-                        # trace.
-                        f = failure.Failure()
-                        logger.error(
-                            "Failed handle request %s.%s on %r: %r: %s",
-                            request_handler.__module__,
-                            request_handler.__name__,
-                            self,
-                            request,
-                            f.getTraceback().rstrip(),
-                        )
-                        respond_with_json(
-                            request,
-                            500,
-                            {
-                                "error": "Internal server error",
-                                "errcode": Codes.UNKNOWN,
-                            },
-                            send_cors=True,
-                            pretty_print=_request_user_agent_is_curl(request),
-                            version_string=self.version_string,
-                        )
-                    finally:
-                        try:
-                            request_metrics.stop(
-                                self.clock, request
-                            )
-                        except Exception as e:
-                            logger.warn("Failed to stop metrics: %r", e)
+                        # record the arrival of the request *after*
+                        # dispatching to the handler, so that the handler
+                        # can update the servlet name in the request
+                        # metrics
+                        requests_counter.inc(request.method,
+                                             request.request_metrics.name)
+                        yield d
     return wrapped_request_handler
 
 
@@ -262,7 +190,6 @@ class JsonResource(HttpServer, resource.Resource):
         self.canonical_json = canonical_json
         self.clock = hs.get_clock()
         self.path_regexs = {}
-        self.version_string = hs.version_string
         self.hs = hs
 
     def register_paths(self, method, path_patterns, callback):
@@ -278,13 +205,9 @@ class JsonResource(HttpServer, resource.Resource):
         self._async_render(request)
         return server.NOT_DONE_YET
 
-    # Disable metric reporting because _async_render does its own metrics.
-    # It does its own metric reporting because _async_render dispatches to
-    # a callback and it's the class name of that callback we want to report
-    # against rather than the JsonResource itself.
-    @request_handler(include_metrics=True)
+    @wrap_json_request_handler
     @defer.inlineCallbacks
-    def _async_render(self, request, request_metrics):
+    def _async_render(self, request):
         """ This gets called from render() every time someone sends us a request.
             This checks if anyone has registered a callback for that method and
             path.
@@ -296,9 +219,7 @@ class JsonResource(HttpServer, resource.Resource):
             servlet_classname = servlet_instance.__class__.__name__
         else:
             servlet_classname = "%r" % callback
-
-        request_metrics.name = servlet_classname
-        requests_counter.inc(request.method, servlet_classname)
+        request.request_metrics.name = servlet_classname
 
         # Now trigger the callback. If it returns a response, we send it
         # here. If it throws an exception, that is handled by the wrapper
@@ -345,15 +266,12 @@ class JsonResource(HttpServer, resource.Resource):
 
     def _send_response(self, request, code, response_json_object,
                        response_code_message=None):
-        outgoing_responses_counter.inc(request.method, str(code))
-
         # TODO: Only enable CORS for the requests that need it.
         respond_with_json(
             request, code, response_json_object,
             send_cors=True,
             response_code_message=response_code_message,
             pretty_print=_request_user_agent_is_curl(request),
-            version_string=self.version_string,
             canonical_json=self.canonical_json,
         )
 
@@ -386,54 +304,6 @@ def _unrecognised_request_handler(request):
     raise UnrecognizedRequestError()
 
 
-class RequestMetrics(object):
-    def start(self, clock, name):
-        self.start = clock.time_msec()
-        self.start_context = LoggingContext.current_context()
-        self.name = name
-
-    def stop(self, clock, request):
-        context = LoggingContext.current_context()
-
-        tag = ""
-        if context:
-            tag = context.tag
-
-            if context != self.start_context:
-                logger.warn(
-                    "Context have unexpectedly changed %r, %r",
-                    context, self.start_context
-                )
-                return
-
-        response_count.inc(request.method, self.name, tag)
-
-        response_timer.inc_by(
-            clock.time_msec() - self.start, request.method,
-            self.name, tag
-        )
-
-        ru_utime, ru_stime = context.get_resource_usage()
-
-        response_ru_utime.inc_by(
-            ru_utime, request.method, self.name, tag
-        )
-        response_ru_stime.inc_by(
-            ru_stime, request.method, self.name, tag
-        )
-        response_db_txn_count.inc_by(
-            context.db_txn_count, request.method, self.name, tag
-        )
-        response_db_txn_duration.inc_by(
-            context.db_txn_duration_ms / 1000., request.method, self.name, tag
-        )
-        response_db_sched_duration.inc_by(
-            context.db_sched_duration_ms / 1000., request.method, self.name, tag
-        )
-
-        response_size.inc_by(request.sentLength, request.method, self.name, tag)
-
-
 class RootRedirect(resource.Resource):
     """Redirects the root '/' path to another path."""
 
@@ -452,7 +322,7 @@ class RootRedirect(resource.Resource):
 
 def respond_with_json(request, code, json_object, send_cors=False,
                       response_code_message=None, pretty_print=False,
-                      version_string="", canonical_json=True):
+                      canonical_json=True):
     # could alternatively use request.notifyFinish() and flip a flag when
     # the Deferred fires, but since the flag is RIGHT THERE it seems like
     # a waste.
@@ -474,12 +344,11 @@ def respond_with_json(request, code, json_object, send_cors=False,
         request, code, json_bytes,
         send_cors=send_cors,
         response_code_message=response_code_message,
-        version_string=version_string
     )
 
 
 def respond_with_json_bytes(request, code, json_bytes, send_cors=False,
-                            version_string="", response_code_message=None):
+                            response_code_message=None):
     """Sends encoded JSON in response to the given request.
 
     Args:
@@ -493,7 +362,6 @@ def respond_with_json_bytes(request, code, json_bytes, send_cors=False,
 
     request.setResponseCode(code, message=response_code_message)
     request.setHeader(b"Content-Type", b"application/json")
-    request.setHeader(b"Server", version_string)
     request.setHeader(b"Content-Length", b"%d" % (len(json_bytes),))
     request.setHeader(b"Cache-Control", b"no-cache, no-store, must-revalidate")
 
@@ -546,6 +414,6 @@ def _request_user_agent_is_curl(request):
         b"User-Agent", default=[]
     )
     for user_agent in user_agents:
-        if "curl" in user_agent:
+        if b"curl" in user_agent:
             return True
     return False

synapse/http/site.py

@@ -12,24 +12,48 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from synapse.util.logcontext import LoggingContext
-from twisted.web.server import Site, Request
-
 import contextlib
 import logging
 import re
 import time
 
+from twisted.web.server import Site, Request
+
+from synapse.http.request_metrics import RequestMetrics
+from synapse.util.logcontext import LoggingContext
+
+logger = logging.getLogger(__name__)
+
 ACCESS_TOKEN_RE = re.compile(br'(\?.*access(_|%5[Ff])token=)[^&]*(.*)$')
 
+_next_request_seq = 0
+
 
 class SynapseRequest(Request):
+    """Class which encapsulates an HTTP request to synapse.
+
+    All of the requests processed in synapse are of this type.
+
+    It extends twisted's twisted.web.server.Request, and adds:
+     * Unique request ID
+     * Redaction of access_token query-params in __repr__
+     * Logging at start and end
+     * Metrics to record CPU, wallclock and DB time by endpoint.
+
+    It provides a method `processing` which should be called by the Resource
+    which is handling the request, and returns a context manager.
+
+    """
     def __init__(self, site, *args, **kw):
         Request.__init__(self, *args, **kw)
         self.site = site
         self.authenticated_entity = None
         self.start_time = 0
 
+        global _next_request_seq
+        self.request_seq = _next_request_seq
+        _next_request_seq += 1
+
     def __repr__(self):
         # We overwrite this so that we don't log ``access_token``
         return '<%s at 0x%x method=%s uri=%s clientproto=%s site=%s>' % (
@@ -41,6 +65,9 @@ class SynapseRequest(Request):
             self.site.site_tag,
         )
 
+    def get_request_id(self):
+        return "%s-%i" % (self.method, self.request_seq)
+
     def get_redacted_uri(self):
         return ACCESS_TOKEN_RE.sub(
             br'\1<redacted>\3',
@@ -50,7 +77,16 @@ class SynapseRequest(Request):
     def get_user_agent(self):
         return self.requestHeaders.getRawHeaders(b"User-Agent", [None])[-1]
 
-    def started_processing(self):
+    def render(self, resrc):
+        # override the Server header which is set by twisted
+        self.setHeader("Server", self.site.server_version_string)
+        return Request.render(self, resrc)
+
+    def _started_processing(self, servlet_name):
+        self.start_time = int(time.time() * 1000)
+        self.request_metrics = RequestMetrics()
+        self.request_metrics.start(self.start_time, name=servlet_name)
+
         self.site.access_logger.info(
             "%s - %s - Received request: %s %s",
             self.getClientIP(),
@@ -58,10 +94,8 @@ class SynapseRequest(Request):
             self.method,
             self.get_redacted_uri()
         )
-        self.start_time = int(time.time() * 1000)
-
-    def finished_processing(self):
 
+    def _finished_processing(self):
         try:
             context = LoggingContext.current_context()
             ru_utime, ru_stime = context.get_resource_usage()
@@ -72,6 +106,8 @@ class SynapseRequest(Request):
             ru_utime, ru_stime = (0, 0)
             db_txn_count, db_txn_duration_ms = (0, 0)
 
+        end_time = int(time.time() * 1000)
+
         self.site.access_logger.info(
             "%s - %s - {%s}"
             " Processed request: %dms (%dms, %dms) (%dms/%dms/%d)"
@@ -79,7 +115,7 @@ class SynapseRequest(Request):
             self.getClientIP(),
             self.site.site_tag,
             self.authenticated_entity,
-            int(time.time() * 1000) - self.start_time,
+            end_time - self.start_time,
             int(ru_utime * 1000),
             int(ru_stime * 1000),
             db_sched_duration_ms,
@@ -93,11 +129,38 @@ class SynapseRequest(Request):
             self.get_user_agent(),
         )
 
+        try:
+            self.request_metrics.stop(end_time, self)
+        except Exception as e:
+            logger.warn("Failed to stop metrics: %r", e)
+
     @contextlib.contextmanager
-    def processing(self):
-        self.started_processing()
+    def processing(self, servlet_name):
+        """Record the fact that we are processing this request.
+
+        Returns a context manager; the correct way to use this is:
+
+        @defer.inlineCallbacks
+        def handle_request(request):
+            with request.processing("FooServlet"):
+                yield really_handle_the_request()
+
+        This will log the request's arrival. Once the context manager is
+        closed, the completion of the request will be logged, and the various
+        metrics will be updated.
+
+        Args:
+            servlet_name (str): the name of the servlet which will be
+                processing this request. This is used in the metrics.
+
+                It is possible to update this afterwards by updating
+                self.request_metrics.servlet_name.
+        """
+        # TODO: we should probably just move this into render() and finish(),
+        # to save having to call a separate method.
+        self._started_processing(servlet_name)
         yield
-        self.finished_processing()
+        self._finished_processing()
 
 
 class XForwardedForRequest(SynapseRequest):
@@ -135,7 +198,8 @@ class SynapseSite(Site):
     Subclass of a twisted http Site that does access logging with python's
     standard logging
     """
-    def __init__(self, logger_name, site_tag, config, resource, *args, **kwargs):
+    def __init__(self, logger_name, site_tag, config, resource,
+                 server_version_string, *args, **kwargs):
         Site.__init__(self, resource, *args, **kwargs)
 
         self.site_tag = site_tag
@@ -143,6 +207,7 @@ class SynapseSite(Site):
         proxied = config.get("x_forwarded", False)
         self.requestFactory = SynapseRequestFactory(self, proxied)
         self.access_logger = logging.getLogger(logger_name)
+        self.server_version_string = server_version_string
 
     def log(self, request):
         pass

synapse/metrics/metric.py

@@ -16,6 +16,7 @@
 
 from itertools import chain
 import logging
+import re
 
 logger = logging.getLogger(__name__)
 
@@ -56,8 +57,7 @@ class BaseMetric(object):
         return not len(self.labels)
 
     def _render_labelvalue(self, value):
-        # TODO: escape backslashes, quotes and newlines
-        return '"%s"' % (value)
+        return '"%s"' % (_escape_label_value(value),)
 
     def _render_key(self, values):
         if self.is_scalar():
@@ -71,7 +71,8 @@ class BaseMetric(object):
         """Render this metric for a single set of labels
 
         Args:
-            label_values (list[str]): values for each of the labels
+            label_values (list[object]): values for each of the labels,
+                (which get stringified).
             value: value of the metric at with these labels
 
         Returns:
@@ -299,3 +300,29 @@ class MemoryUsageMetric(object):
             "process_psutil_rss:total %d" % sum_rss,
             "process_psutil_rss:count %d" % len_rss,
         ]
+
+
+def _escape_character(m):
+    """Replaces a single character with its escape sequence.
+
+    Args:
+        m (re.MatchObject): A match object whose first group is the single
+            character to replace
+
+    Returns:
+        str
+    """
+    c = m.group(1)
+    if c == "\\":
+        return "\\\\"
+    elif c == "\"":
+        return "\\\""
+    elif c == "\n":
+        return "\\n"
+    return c
+
+
+def _escape_label_value(value):
+    """Takes a label value and escapes quotes, newlines and backslashes
+    """
+    return re.sub(r"([\n\"\\])", _escape_character, str(value))

synapse/notifier.py

@@ -14,14 +14,17 @@
 # limitations under the License.
 
 from twisted.internet import defer
+
 from synapse.api.constants import EventTypes, Membership
 from synapse.api.errors import AuthError
 from synapse.handlers.presence import format_user_presence_state
 
-from synapse.util import DeferredTimedOutError
 from synapse.util.logutils import log_function
-from synapse.util.async import ObservableDeferred
-from synapse.util.logcontext import PreserveLoggingContext, preserve_fn
+from synapse.util.async import (
+    ObservableDeferred, add_timeout_to_deferred,
+    DeferredTimeoutError,
+)
+from synapse.util.logcontext import PreserveLoggingContext, run_in_background
 from synapse.util.metrics import Measure
 from synapse.types import StreamToken
 from synapse.visibility import filter_events_for_client
@@ -251,9 +254,7 @@ class Notifier(object):
     def _on_new_room_event(self, event, room_stream_id, extra_users=[]):
         """Notify any user streams that are interested in this room event"""
         # poke any interested application service.
-        preserve_fn(self.appservice_handler.notify_interested_services)(
-            room_stream_id
-        )
+        run_in_background(self._notify_app_services, room_stream_id)
 
         if self.federation_sender:
             self.federation_sender.notify_new_events(room_stream_id)
@@ -267,6 +268,13 @@ class Notifier(object):
             rooms=[event.room_id],
         )
 
+    @defer.inlineCallbacks
+    def _notify_app_services(self, room_stream_id):
+        try:
+            yield self.appservice_handler.notify_interested_services(room_stream_id)
+        except Exception:
+            logger.exception("Error notifying application services of event")
+
     def on_new_event(self, stream_key, new_token, users=[], rooms=[]):
         """ Used to inform listeners that something has happend event wise.
 
@@ -331,11 +339,12 @@ class Notifier(object):
                     # Now we wait for the _NotifierUserStream to be told there
                     # is a new token.
                     listener = user_stream.new_listener(prev_token)
+                    add_timeout_to_deferred(
+                        listener.deferred,
+                        (end_time - now) / 1000.,
+                    )
                     with PreserveLoggingContext():
-                        yield self.clock.time_bound_deferred(
-                            listener.deferred,
-                            time_out=(end_time - now) / 1000.
-                        )
+                        yield listener.deferred
 
                     current_token = user_stream.current_token
 
@@ -346,7 +355,7 @@ class Notifier(object):
                     # Update the prev_token to the current_token since nothing
                     # has happened between the old prev_token and the current_token
                     prev_token = current_token
-                except DeferredTimedOutError:
+                except DeferredTimeoutError:
                     break
                 except defer.CancelledError:
                     break
@@ -551,13 +560,14 @@ class Notifier(object):
             if end_time <= now:
                 break
 
+            add_timeout_to_deferred(
+                listener.deferred.addTimeout,
+                (end_time - now) / 1000.,
+            )
             try:
                 with PreserveLoggingContext():
-                    yield self.clock.time_bound_deferred(
-                        listener.deferred,
-                        time_out=(end_time - now) / 1000.
-                    )
-            except DeferredTimedOutError:
+                    yield listener.deferred
+            except DeferredTimeoutError:
                 break
             except defer.CancelledError:
                 break

synapse/push/emailpusher.py

@@ -77,10 +77,13 @@ class EmailPusher(object):
     @defer.inlineCallbacks
     def on_started(self):
         if self.mailer is not None:
-            self.throttle_params = yield self.store.get_throttle_params_by_room(
-                self.pusher_id
-            )
-            yield self._process()
+            try:
+                self.throttle_params = yield self.store.get_throttle_params_by_room(
+                    self.pusher_id
+                )
+                yield self._process()
+            except Exception:
+                logger.exception("Error starting email pusher")
 
     def on_stop(self):
         if self.timed_call:

synapse/push/httppusher.py

@@ -18,8 +18,8 @@ import logging
 from twisted.internet import defer, reactor
 from twisted.internet.error import AlreadyCalled, AlreadyCancelled
 
-import push_rule_evaluator
-import push_tools
+from . import push_rule_evaluator
+from . import push_tools
 import synapse
 from synapse.push import PusherConfigException
 from synapse.util.logcontext import LoggingContext
@@ -94,7 +94,10 @@ class HttpPusher(object):
 
     @defer.inlineCallbacks
     def on_started(self):
-        yield self._process()
+        try:
+            yield self._process()
+        except Exception:
+            logger.exception("Error starting http pusher")
 
     @defer.inlineCallbacks
     def on_new_notifications(self, min_stream_ordering, max_stream_ordering):

synapse/push/pusher.py

@@ -13,7 +13,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from httppusher import HttpPusher
+from .httppusher import HttpPusher
 
 import logging
 logger = logging.getLogger(__name__)

synapse/push/pusherpool.py

@@ -14,13 +14,13 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import logging
+
 from twisted.internet import defer
 
-from .pusher import PusherFactory
-from synapse.util.logcontext import make_deferred_yieldable, preserve_fn
+from synapse.push.pusher import PusherFactory
 from synapse.util.async import run_on_reactor
-
-import logging
+from synapse.util.logcontext import make_deferred_yieldable, run_in_background
 
 logger = logging.getLogger(__name__)
 
@@ -137,12 +137,15 @@ class PusherPool:
                 if u in self.pushers:
                     for p in self.pushers[u].values():
                         deferreds.append(
-                            preserve_fn(p.on_new_notifications)(
-                                min_stream_id, max_stream_id
+                            run_in_background(
+                                p.on_new_notifications,
+                                min_stream_id, max_stream_id,
                             )
                         )
 
-            yield make_deferred_yieldable(defer.gatherResults(deferreds))
+            yield make_deferred_yieldable(
+                defer.gatherResults(deferreds, consumeErrors=True),
+            )
         except Exception:
             logger.exception("Exception in pusher on_new_notifications")
 
@@ -164,10 +167,15 @@ class PusherPool:
                 if u in self.pushers:
                     for p in self.pushers[u].values():
                         deferreds.append(
-                            preserve_fn(p.on_new_receipts)(min_stream_id, max_stream_id)
+                            run_in_background(
+                                p.on_new_receipts,
+                                min_stream_id, max_stream_id,
+                            )
                         )
 
-            yield make_deferred_yieldable(defer.gatherResults(deferreds))
+            yield make_deferred_yieldable(
+                defer.gatherResults(deferreds, consumeErrors=True),
+            )
         except Exception:
             logger.exception("Exception in pusher on_new_receipts")
 
@@ -207,7 +215,7 @@ class PusherPool:
                 if appid_pushkey in byuser:
                     byuser[appid_pushkey].on_stop()
                 byuser[appid_pushkey] = p
-                preserve_fn(p.on_started)()
+                run_in_background(p.on_started)
 
         logger.info("Started pushers")
 

synapse/python_dependencies.py

@@ -1,5 +1,6 @@
 # Copyright 2015, 2016 OpenMarket Ltd
 # Copyright 2017 Vector Creations Ltd
+# Copyright 2018 New Vector Ltd
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -18,6 +19,18 @@ from distutils.version import LooseVersion
 
 logger = logging.getLogger(__name__)
 
+# this dict maps from python package name to a list of modules we expect it to
+# provide.
+#
+# the key is a "requirement specifier", as used as a parameter to `pip
+# install`[1], or an `install_requires` argument to `setuptools.setup` [2].
+#
+# the value is a sequence of strings; each entry should be the name of the
+# python module, optionally followed by a version assertion which can be either
+# ">=<ver>" or "==<ver>".
+#
+# [1] https://pip.pypa.io/en/stable/reference/pip_install/#requirement-specifiers.
+# [2] https://setuptools.readthedocs.io/en/latest/setuptools.html#declaring-dependencies
 REQUIREMENTS = {
     "jsonschema>=2.5.1": ["jsonschema>=2.5.1"],
     "frozendict>=0.4": ["frozendict"],
@@ -27,7 +40,10 @@ REQUIREMENTS = {
     "pynacl>=1.2.1": ["nacl>=1.2.1", "nacl.bindings"],
     "service_identity>=1.0.0": ["service_identity>=1.0.0"],
     "Twisted>=16.0.0": ["twisted>=16.0.0"],
-    "pyopenssl>=0.14": ["OpenSSL>=0.14"],
+
+    # We use crypto.get_elliptic_curve which is only supported in >=0.15
+    "pyopenssl>=0.15": ["OpenSSL>=0.15"],
+
     "pyyaml": ["yaml"],
     "pyasn1": ["pyasn1"],
     "daemonize": ["daemonize"],
@@ -39,6 +55,7 @@ REQUIREMENTS = {
     "pymacaroons-pynacl": ["pymacaroons"],
     "msgpack-python>=0.3.0": ["msgpack"],
     "phonenumbers>=8.2.0": ["phonenumbers"],
+    "six": ["six"],
 }
 CONDITIONAL_REQUIREMENTS = {
     "web_client": {

synapse/replication/tcp/protocol.py

@@ -53,12 +53,12 @@ from twisted.internet import defer
 from twisted.protocols.basic import LineOnlyReceiver
 from twisted.python.failure import Failure
 
-from commands import (
+from .commands import (
     COMMAND_MAP, VALID_CLIENT_COMMANDS, VALID_SERVER_COMMANDS,
     ErrorCommand, ServerCommand, RdataCommand, PositionCommand, PingCommand,
     NameCommand, ReplicateCommand, UserSyncCommand, SyncCommand,
 )
-from streams import STREAMS_MAP
+from .streams import STREAMS_MAP
 
 from synapse.util.stringutils import random_string
 from synapse.metrics.metric import CounterMetric

synapse/replication/tcp/resource.py

@@ -18,8 +18,8 @@
 from twisted.internet import defer, reactor
 from twisted.internet.protocol import Factory
 
-from streams import STREAMS_MAP, FederationStream
-from protocol import ServerReplicationStreamProtocol
+from .streams import STREAMS_MAP, FederationStream
+from .protocol import ServerReplicationStreamProtocol
 
 from synapse.util.metrics import Measure, measure_func
 

synapse/rest/client/v1/admin.py

@@ -168,11 +168,24 @@ class PurgeHistoryRestServlet(ClientV1RestServlet):
                 yield self.store.find_first_stream_ordering_after_ts(ts)
             )
 
-            (_, depth, _) = (
+            room_event_after_stream_ordering = (
                 yield self.store.get_room_event_after_stream_ordering(
                     room_id, stream_ordering,
                 )
             )
+            if room_event_after_stream_ordering:
+                (_, depth, _) = room_event_after_stream_ordering
+            else:
+                logger.warn(
+                    "[purge] purging events not possible: No event found "
+                    "(received_ts %i => stream_ordering %i)",
+                    ts, stream_ordering,
+                )
+                raise SynapseError(
+                    404,
+                    "there is no event to be purged",
+                    errcode=Codes.NOT_FOUND,
+                )
             logger.info(
                 "[purge] purging up to depth %i (received_ts %i => "
                 "stream_ordering %i)",

synapse/rest/client/v1/base.py

@@ -52,6 +52,10 @@ class ClientV1RestServlet(RestServlet):
     """A base Synapse REST Servlet for the client version 1 API.
     """
 
+    # This subclass was presumably created to allow the auth for the v1
+    # protocol version to be different, however this behaviour was removed.
+    # it may no longer be necessary
+
     def __init__(self, hs):
         """
         Args:
@@ -59,5 +63,5 @@ class ClientV1RestServlet(RestServlet):
         """
         self.hs = hs
         self.builder_factory = hs.get_event_builder_factory()
-        self.auth = hs.get_v1auth()
+        self.auth = hs.get_auth()
         self.txns = HttpTransactionCache(hs.get_clock())

synapse/rest/client/v1/login.py

@@ -25,7 +25,7 @@ from .base import ClientV1RestServlet, client_path_patterns
 
 import simplejson as json
 import urllib
-import urlparse
+from six.moves.urllib import parse as urlparse
 
 import logging
 from saml2 import BINDING_HTTP_POST

synapse/rest/client/v1/pusher.py

@@ -150,7 +150,7 @@ class PushersRemoveRestServlet(RestServlet):
         super(RestServlet, self).__init__()
         self.hs = hs
         self.notifier = hs.get_notifier()
-        self.auth = hs.get_v1auth()
+        self.auth = hs.get_auth()
         self.pusher_pool = self.hs.get_pusherpool()
 
     @defer.inlineCallbacks
@@ -176,7 +176,6 @@ class PushersRemoveRestServlet(RestServlet):
 
         request.setResponseCode(200)
         request.setHeader(b"Content-Type", b"text/html; charset=utf-8")
-        request.setHeader(b"Server", self.hs.version_string)
         request.setHeader(b"Content-Length", b"%d" % (
             len(PushersRemoveRestServlet.SUCCESS_HTML),
         ))

synapse/rest/client/v1/register.py

@@ -30,6 +30,8 @@ from hashlib import sha1
 import hmac
 import logging
 
+from six import string_types
+
 logger = logging.getLogger(__name__)
 
 
@@ -333,11 +335,11 @@ class RegisterRestServlet(ClientV1RestServlet):
     def _do_shared_secret(self, request, register_json, session):
         yield run_on_reactor()
 
-        if not isinstance(register_json.get("mac", None), basestring):
+        if not isinstance(register_json.get("mac", None), string_types):
             raise SynapseError(400, "Expected mac.")
-        if not isinstance(register_json.get("user", None), basestring):
+        if not isinstance(register_json.get("user", None), string_types):
             raise SynapseError(400, "Expected 'user' key.")
-        if not isinstance(register_json.get("password", None), basestring):
+        if not isinstance(register_json.get("password", None), string_types):
             raise SynapseError(400, "Expected 'password' key.")
 
         if not self.hs.config.registration_shared_secret:
@@ -358,14 +360,14 @@ class RegisterRestServlet(ClientV1RestServlet):
         got_mac = str(register_json["mac"])
 
         want_mac = hmac.new(
-            key=self.hs.config.registration_shared_secret,
+            key=self.hs.config.registration_shared_secret.encode(),
             digestmod=sha1,
         )
         want_mac.update(user)
-        want_mac.update("\x00")
+        want_mac.update(b"\x00")
         want_mac.update(password)
-        want_mac.update("\x00")
-        want_mac.update("admin" if admin else "notadmin")
+        want_mac.update(b"\x00")
+        want_mac.update(b"admin" if admin else b"notadmin")
         want_mac = want_mac.hexdigest()
 
         if compare_digest(want_mac, got_mac):

synapse/rest/client/v1/room.py

@@ -28,8 +28,9 @@ from synapse.http.servlet import (
     parse_json_object_from_request, parse_string, parse_integer
 )
 
+from six.moves.urllib import parse as urlparse
+
 import logging
-import urllib
 import simplejson as json
 
 logger = logging.getLogger(__name__)
@@ -433,7 +434,7 @@ class RoomMessageListRestServlet(ClientV1RestServlet):
         as_client_event = "raw" not in request.args
         filter_bytes = request.args.get("filter", None)
         if filter_bytes:
-            filter_json = urllib.unquote(filter_bytes[-1]).decode("UTF-8")
+            filter_json = urlparse.unquote(filter_bytes[-1]).decode("UTF-8")
             event_filter = Filter(json.loads(filter_json))
         else:
             event_filter = None
@@ -718,8 +719,8 @@ class RoomTypingRestServlet(ClientV1RestServlet):
     def on_PUT(self, request, room_id, user_id):
         requester = yield self.auth.get_user_by_req(request)
 
-        room_id = urllib.unquote(room_id)
-        target_user = UserID.from_string(urllib.unquote(user_id))
+        room_id = urlparse.unquote(room_id)
+        target_user = UserID.from_string(urlparse.unquote(user_id))
 
         content = parse_json_object_from_request(request)
 

synapse/rest/client/v2_alpha/auth.py

@@ -129,7 +129,6 @@ class AuthRestServlet(RestServlet):
             html_bytes = html.encode("utf8")
             request.setResponseCode(200)
             request.setHeader(b"Content-Type", b"text/html; charset=utf-8")
-            request.setHeader(b"Server", self.hs.version_string)
             request.setHeader(b"Content-Length", b"%d" % (len(html_bytes),))
 
             request.write(html_bytes)
@@ -175,7 +174,6 @@ class AuthRestServlet(RestServlet):
             html_bytes = html.encode("utf8")
             request.setResponseCode(200)
             request.setHeader(b"Content-Type", b"text/html; charset=utf-8")
-            request.setHeader(b"Server", self.hs.version_string)
             request.setHeader(b"Content-Length", b"%d" % (len(html_bytes),))
 
             request.write(html_bytes)

synapse/rest/client/v2_alpha/notifications.py

@@ -88,7 +88,7 @@ class NotificationsServlet(RestServlet):
                     pa["topological_ordering"], pa["stream_ordering"]
                 )
             returned_push_actions.append(returned_pa)
-            next_token = pa["stream_ordering"]
+            next_token = str(pa["stream_ordering"])
 
         defer.returnValue((200, {
             "notifications": returned_push_actions,

synapse/rest/client/v2_alpha/register.py

@@ -35,6 +35,8 @@ from hashlib import sha1
 from synapse.util.async import run_on_reactor
 from synapse.util.ratelimitutils import FederationRateLimiter
 
+from six import string_types
+
 
 # We ought to be using hmac.compare_digest() but on older pythons it doesn't
 # exist. It's a _really minor_ security flaw to use plain string comparison
@@ -210,14 +212,14 @@ class RegisterRestServlet(RestServlet):
         # in sessions. Pull out the username/password provided to us.
         desired_password = None
         if 'password' in body:
-            if (not isinstance(body['password'], basestring) or
+            if (not isinstance(body['password'], string_types) or
                     len(body['password']) > 512):
                 raise SynapseError(400, "Invalid password")
             desired_password = body["password"]
 
         desired_username = None
         if 'username' in body:
-            if (not isinstance(body['username'], basestring) or
+            if (not isinstance(body['username'], string_types) or
                     len(body['username']) > 512):
                 raise SynapseError(400, "Invalid username")
             desired_username = body['username']
@@ -243,7 +245,7 @@ class RegisterRestServlet(RestServlet):
 
             access_token = get_access_token_from_request(request)
 
-            if isinstance(desired_username, basestring):
+            if isinstance(desired_username, string_types):
                 result = yield self._do_appservice_registration(
                     desired_username, access_token, body
                 )
@@ -464,7 +466,7 @@ class RegisterRestServlet(RestServlet):
         # includes the password and admin flag in the hashed text. Why are
         # these different?
         want_mac = hmac.new(
-            key=self.hs.config.registration_shared_secret,
+            key=self.hs.config.registration_shared_secret.encode(),
             msg=user,
             digestmod=sha1,
         ).hexdigest()

synapse/rest/key/v1/server_key_resource.py

@@ -49,7 +49,6 @@ class LocalKey(Resource):
     """
 
     def __init__(self, hs):
-        self.version_string = hs.version_string
         self.response_body = encode_canonical_json(
             self.response_json_object(hs.config)
         )
@@ -84,7 +83,6 @@ class LocalKey(Resource):
     def render_GET(self, request):
         return respond_with_json_bytes(
             request, 200, self.response_body,
-            version_string=self.version_string
         )
 
     def getChild(self, name, request):

synapse/rest/key/v2/local_key_resource.py

@@ -63,7 +63,6 @@ class LocalKey(Resource):
     isLeaf = True
 
     def __init__(self, hs):
-        self.version_string = hs.version_string
         self.config = hs.config
         self.clock = hs.clock
         self.update_response_body(self.clock.time_msec())
@@ -115,5 +114,4 @@ class LocalKey(Resource):
             self.update_response_body(time_now)
         return respond_with_json_bytes(
             request, 200, self.response_body,
-            version_string=self.version_string
         )

synapse/rest/key/v2/remote_key_resource.py

@@ -12,7 +12,9 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from synapse.http.server import request_handler, respond_with_json_bytes
+from synapse.http.server import (
+    respond_with_json_bytes, wrap_json_request_handler,
+)
 from synapse.http.servlet import parse_integer, parse_json_object_from_request
 from synapse.api.errors import SynapseError, Codes
 from synapse.crypto.keyring import KeyLookupError
@@ -91,7 +93,6 @@ class RemoteKey(Resource):
     def __init__(self, hs):
         self.keyring = hs.get_keyring()
         self.store = hs.get_datastore()
-        self.version_string = hs.version_string
         self.clock = hs.get_clock()
         self.federation_domain_whitelist = hs.config.federation_domain_whitelist
 
@@ -99,7 +100,7 @@ class RemoteKey(Resource):
         self.async_render_GET(request)
         return NOT_DONE_YET
 
-    @request_handler()
+    @wrap_json_request_handler
     @defer.inlineCallbacks
     def async_render_GET(self, request):
         if len(request.postpath) == 1:
@@ -124,7 +125,7 @@ class RemoteKey(Resource):
         self.async_render_POST(request)
         return NOT_DONE_YET
 
-    @request_handler()
+    @wrap_json_request_handler
     @defer.inlineCallbacks
     def async_render_POST(self, request):
         content = parse_json_object_from_request(request)
@@ -240,5 +241,4 @@ class RemoteKey(Resource):
 
             respond_with_json_bytes(
                 request, 200, result_io.getvalue(),
-                version_string=self.version_string
             )

synapse/rest/media/v1/_base.py

@@ -28,7 +28,7 @@ import os
 
 import logging
 import urllib
-import urlparse
+from six.moves.urllib import parse as urlparse
 
 logger = logging.getLogger(__name__)
 
@@ -143,6 +143,7 @@ def respond_with_responder(request, responder, media_type, file_size, upload_nam
         respond_404(request)
         return
 
+    logger.debug("Responding to media request with responder %s")
     add_file_headers(request, media_type, file_size, upload_name)
     with responder:
         yield responder.write_to_consumer(request)

synapse/rest/media/v1/download_resource.py

@@ -12,17 +12,19 @@
 # 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 synapse.http.servlet
-
-from ._base import parse_media_id, respond_404
-from twisted.web.resource import Resource
-from synapse.http.server import request_handler, set_cors_headers
-
-from twisted.web.server import NOT_DONE_YET
-from twisted.internet import defer
-
 import logging
 
+from twisted.internet import defer
+from twisted.web.resource import Resource
+from twisted.web.server import NOT_DONE_YET
+
+from synapse.http.server import (
+    set_cors_headers,
+    wrap_json_request_handler,
+)
+import synapse.http.servlet
+from ._base import parse_media_id, respond_404
+
 logger = logging.getLogger(__name__)
 
 
@@ -35,15 +37,14 @@ class DownloadResource(Resource):
         self.media_repo = media_repo
         self.server_name = hs.hostname
 
-        # Both of these are expected by @request_handler()
+        # this is expected by @wrap_json_request_handler
         self.clock = hs.get_clock()
-        self.version_string = hs.version_string
 
     def render_GET(self, request):
         self._async_render_GET(request)
         return NOT_DONE_YET
 
-    @request_handler()
+    @wrap_json_request_handler
     @defer.inlineCallbacks
     def _async_render_GET(self, request):
         set_cors_headers(request)

synapse/rest/media/v1/media_repository.py

@@ -47,7 +47,7 @@ import shutil
 
 import cgi
 import logging
-import urlparse
+from six.moves.urllib import parse as urlparse
 
 logger = logging.getLogger(__name__)
 

synapse/rest/media/v1/media_storage.py

@@ -255,7 +255,9 @@ class FileResponder(Responder):
         self.open_file = open_file
 
     def write_to_consumer(self, consumer):
-        return FileSender().beginFileTransfer(self.open_file, consumer)
+        return make_deferred_yieldable(
+            FileSender().beginFileTransfer(self.open_file, consumer)
+        )
 
     def __exit__(self, exc_type, exc_val, exc_tb):
         self.open_file.close()

synapse/rest/media/v1/preview_url_resource.py

@@ -35,13 +35,14 @@ from ._base import FileInfo
 from synapse.api.errors import (
     SynapseError, Codes,
 )
-from synapse.util.logcontext import preserve_fn, make_deferred_yieldable
+from synapse.util.logcontext import make_deferred_yieldable, run_in_background
 from synapse.util.stringutils import random_string
 from synapse.util.caches.expiringcache import ExpiringCache
 from synapse.http.client import SpiderHttpClient
 from synapse.http.server import (
-    request_handler, respond_with_json_bytes,
+    respond_with_json_bytes,
     respond_with_json,
+    wrap_json_request_handler,
 )
 from synapse.util.async import ObservableDeferred
 from synapse.util.stringutils import is_ascii
@@ -57,7 +58,6 @@ class PreviewUrlResource(Resource):
 
         self.auth = hs.get_auth()
         self.clock = hs.get_clock()
-        self.version_string = hs.version_string
         self.filepaths = media_repo.filepaths
         self.max_spider_size = hs.config.max_spider_size
         self.server_name = hs.hostname
@@ -90,7 +90,7 @@ class PreviewUrlResource(Resource):
         self._async_render_GET(request)
         return NOT_DONE_YET
 
-    @request_handler()
+    @wrap_json_request_handler
     @defer.inlineCallbacks
     def _async_render_GET(self, request):
 
@@ -144,7 +144,8 @@ class PreviewUrlResource(Resource):
         observable = self._cache.get(url)
 
         if not observable:
-            download = preserve_fn(self._do_preview)(
+            download = run_in_background(
+                self._do_preview,
                 url, requester.user, ts,
             )
             observable = ObservableDeferred(

synapse/rest/media/v1/storage_provider.py

@@ -18,7 +18,7 @@ from twisted.internet import defer, threads
 from .media_storage import FileResponder
 
 from synapse.config._base import Config
-from synapse.util.logcontext import preserve_fn
+from synapse.util.logcontext import run_in_background
 
 import logging
 import os
@@ -87,7 +87,12 @@ class StorageProviderWrapper(StorageProvider):
             return self.backend.store_file(path, file_info)
         else:
             # TODO: Handle errors.
-            preserve_fn(self.backend.store_file)(path, file_info)
+            def store():
+                try:
+                    return self.backend.store_file(path, file_info)
+                except Exception:
+                    logger.exception("Error storing file")
+            run_in_background(store)
             return defer.succeed(None)
 
     def fetch(self, path, file_info):

synapse/rest/media/v1/thumbnail_resource.py

@@ -14,18 +14,21 @@
 # limitations under the License.
 
 
+import logging
+
+from twisted.internet import defer
+from twisted.web.resource import Resource
+from twisted.web.server import NOT_DONE_YET
+
+from synapse.http.server import (
+    set_cors_headers,
+    wrap_json_request_handler,
+)
+from synapse.http.servlet import parse_integer, parse_string
 from ._base import (
-    parse_media_id, respond_404, respond_with_file, FileInfo,
+    FileInfo, parse_media_id, respond_404, respond_with_file,
     respond_with_responder,
 )
-from twisted.web.resource import Resource
-from synapse.http.servlet import parse_string, parse_integer
-from synapse.http.server import request_handler, set_cors_headers
-
-from twisted.web.server import NOT_DONE_YET
-from twisted.internet import defer
-
-import logging
 
 logger = logging.getLogger(__name__)
 
@@ -41,14 +44,13 @@ class ThumbnailResource(Resource):
         self.media_storage = media_storage
         self.dynamic_thumbnails = hs.config.dynamic_thumbnails
         self.server_name = hs.hostname
-        self.version_string = hs.version_string
         self.clock = hs.get_clock()
 
     def render_GET(self, request):
         self._async_render_GET(request)
         return NOT_DONE_YET
 
-    @request_handler()
+    @wrap_json_request_handler
     @defer.inlineCallbacks
     def _async_render_GET(self, request):
         set_cors_headers(request)

synapse/rest/media/v1/upload_resource.py

@@ -13,16 +13,17 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from synapse.http.server import respond_with_json, request_handler
+import logging
+
+from twisted.internet import defer
+from twisted.web.resource import Resource
+from twisted.web.server import NOT_DONE_YET
 
 from synapse.api.errors import SynapseError
-
-from twisted.web.server import NOT_DONE_YET
-from twisted.internet import defer
-
-from twisted.web.resource import Resource
-
-import logging
+from synapse.http.server import (
+    respond_with_json,
+    wrap_json_request_handler,
+)
 
 logger = logging.getLogger(__name__)
 
@@ -40,7 +41,6 @@ class UploadResource(Resource):
         self.server_name = hs.hostname
         self.auth = hs.get_auth()
         self.max_upload_size = hs.config.max_upload_size
-        self.version_string = hs.version_string
         self.clock = hs.get_clock()
 
     def render_POST(self, request):
@@ -51,7 +51,7 @@ class UploadResource(Resource):
         respond_with_json(request, 200, {}, send_cors=True)
         return NOT_DONE_YET
 
-    @request_handler()
+    @wrap_json_request_handler
     @defer.inlineCallbacks
     def _async_render_POST(self, request):
         requester = yield self.auth.get_user_by_req(request)
@@ -81,15 +81,15 @@ class UploadResource(Resource):
         headers = request.requestHeaders
 
         if headers.hasHeader("Content-Type"):
-            media_type = headers.getRawHeaders("Content-Type")[0]
+            media_type = headers.getRawHeaders(b"Content-Type")[0]
         else:
             raise SynapseError(
                 msg="Upload request missing 'Content-Type'",
                 code=400,
             )
 
-        # if headers.hasHeader("Content-Disposition"):
-        #     disposition = headers.getRawHeaders("Content-Disposition")[0]
+        # if headers.hasHeader(b"Content-Disposition"):
+        #     disposition = headers.getRawHeaders(b"Content-Disposition")[0]
         # TODO(markjh): parse content-dispostion
 
         content_uri = yield self.media_repo.create_content(

synapse/server.py

@@ -105,7 +105,6 @@ class HomeServer(object):
         'federation_client',
         'federation_server',
         'handlers',
-        'v1auth',
         'auth',
         'state_handler',
         'state_resolution_handler',
@@ -225,15 +224,6 @@ class HomeServer(object):
     def build_simple_http_client(self):
         return SimpleHttpClient(self)
 
-    def build_v1auth(self):
-        orf = Auth(self)
-        # Matrix spec makes no reference to what HTTP status code is returned,
-        # but the V1 API uses 403 where it means 401, and the webclient
-        # relies on this behaviour, so V1 gets its own copy of the auth
-        # with backwards compat behaviour.
-        orf.TOKEN_NOT_FOUND_HTTP_STATUS = 403
-        return orf
-
     def build_state_handler(self):
         return StateHandler(self)
 

synapse/storage/event_push_actions.py

@@ -448,6 +448,7 @@ class EventPushActionsWorkerStore(SQLBaseStore):
             "add_push_actions_to_staging", _add_push_actions_to_staging_txn
         )
 
+    @defer.inlineCallbacks
     def remove_push_actions_from_staging(self, event_id):
         """Called if we failed to persist the event to ensure that stale push
         actions don't build up in the DB
@@ -456,13 +457,22 @@ class EventPushActionsWorkerStore(SQLBaseStore):
             event_id (str)
         """
 
-        return self._simple_delete(
-            table="event_push_actions_staging",
-            keyvalues={
-                "event_id": event_id,
-            },
-            desc="remove_push_actions_from_staging",
-        )
+        try:
+            res = yield self._simple_delete(
+                table="event_push_actions_staging",
+                keyvalues={
+                    "event_id": event_id,
+                },
+                desc="remove_push_actions_from_staging",
+            )
+            defer.returnValue(res)
+        except Exception:
+            # this method is called from an exception handler, so propagating
+            # another exception here really isn't helpful - there's nothing
+            # the caller can do about it. Just log the exception and move on.
+            logger.exception(
+                "Error removing push actions after event persistence failure",
+            )
 
     @defer.inlineCallbacks
     def _find_stream_orderings_for_times(self):

synapse/storage/events.py

@@ -22,7 +22,6 @@ import logging
 import simplejson as json
 from twisted.internet import defer
 
-
 from synapse.storage.events_worker import EventsWorkerStore
 from synapse.util.async import ObservableDeferred
 from synapse.util.frozenutils import frozendict_json_encoder
@@ -425,7 +424,9 @@ class EventsStore(EventsWorkerStore):
                             )
                             current_state = yield self._get_new_state_after_events(
                                 room_id,
-                                ev_ctx_rm, new_latest_event_ids,
+                                ev_ctx_rm,
+                                latest_event_ids,
+                                new_latest_event_ids,
                             )
                             if current_state is not None:
                                 current_state_for_room[room_id] = current_state
@@ -513,7 +514,8 @@ class EventsStore(EventsWorkerStore):
         defer.returnValue(new_latest_event_ids)
 
     @defer.inlineCallbacks
-    def _get_new_state_after_events(self, room_id, events_context, new_latest_event_ids):
+    def _get_new_state_after_events(self, room_id, events_context, old_latest_event_ids,
+                                    new_latest_event_ids):
         """Calculate the current state dict after adding some new events to
         a room
 
@@ -524,6 +526,9 @@ class EventsStore(EventsWorkerStore):
             events_context (list[(EventBase, EventContext)]):
                 events and contexts which are being added to the room
 
+            old_latest_event_ids (iterable[str]):
+                the old forward extremities for the room.
+
             new_latest_event_ids (iterable[str]):
                 the new forward extremities for the room.
 
@@ -534,64 +539,89 @@ class EventsStore(EventsWorkerStore):
         """
 
         if not new_latest_event_ids:
-            defer.returnValue({})
+            return
 
         # map from state_group to ((type, key) -> event_id) state map
-        state_groups = {}
-        missing_event_ids = []
-        was_updated = False
+        state_groups_map = {}
+        for ev, ctx in events_context:
+            if ctx.state_group is None:
+                # I don't think this can happen, but let's double-check
+                raise Exception(
+                    "Context for new extremity event %s has no state "
+                    "group" % (ev.event_id, ),
+                )
+
+            if ctx.state_group in state_groups_map:
+                continue
+
+            state_groups_map[ctx.state_group] = ctx.current_state_ids
+
+        # We need to map the event_ids to their state groups. First, let's
+        # check if the event is one we're persisting, in which case we can
+        # pull the state group from its context.
+        # Otherwise we need to pull the state group from the database.
+
+        # Set of events we need to fetch groups for. (We know none of the old
+        # extremities are going to be in events_context).
+        missing_event_ids = set(old_latest_event_ids)
+
+        event_id_to_state_group = {}
         for event_id in new_latest_event_ids:
-            # First search in the list of new events we're adding,
-            # and then use the current state from that
+            # First search in the list of new events we're adding.
             for ev, ctx in events_context:
                 if event_id == ev.event_id:
-                    if ctx.current_state_ids is None:
-                        raise Exception("Unknown current state")
-
-                    if ctx.state_group is None:
-                        # I don't think this can happen, but let's double-check
-                        raise Exception(
-                            "Context for new extremity event %s has no state "
-                            "group" % (event_id, ),
-                        )
-
-                    # If we've already seen the state group don't bother adding
-                    # it to the state sets again
-                    if ctx.state_group not in state_groups:
-                        state_groups[ctx.state_group] = ctx.current_state_ids
-                        if ctx.delta_ids or hasattr(ev, "state_key"):
-                            was_updated = True
+                    event_id_to_state_group[event_id] = ctx.state_group
                     break
             else:
                 # If we couldn't find it, then we'll need to pull
                 # the state from the database
-                was_updated = True
-                missing_event_ids.append(event_id)
-
-        if not was_updated:
-            return
+                missing_event_ids.add(event_id)
 
         if missing_event_ids:
-            # Now pull out the state for any missing events from DB
+            # Now pull out the state groups for any missing events from DB
             event_to_groups = yield self._get_state_group_for_events(
                 missing_event_ids,
             )
+            event_id_to_state_group.update(event_to_groups)
 
-            groups = set(event_to_groups.itervalues()) - set(state_groups.iterkeys())
+        # State groups of old_latest_event_ids
+        old_state_groups = set(
+            event_id_to_state_group[evid] for evid in old_latest_event_ids
+        )
 
-            if groups:
-                group_to_state = yield self._get_state_for_groups(groups)
-                state_groups.update(group_to_state)
+        # State groups of new_latest_event_ids
+        new_state_groups = set(
+            event_id_to_state_group[evid] for evid in new_latest_event_ids
+        )
 
-        if len(state_groups) == 1:
+        # If they old and new groups are the same then we don't need to do
+        # anything.
+        if old_state_groups == new_state_groups:
+            return
+
+        # Now that we have calculated new_state_groups we need to get
+        # their state IDs so we can resolve to a single state set.
+        missing_state = new_state_groups - set(state_groups_map)
+        if missing_state:
+            group_to_state = yield self._get_state_for_groups(missing_state)
+            state_groups_map.update(group_to_state)
+
+        if len(new_state_groups) == 1:
             # If there is only one state group, then we know what the current
             # state is.
-            defer.returnValue(state_groups.values()[0])
+            defer.returnValue(state_groups_map[new_state_groups.pop()])
+
+        # Ok, we need to defer to the state handler to resolve our state sets.
 
         def get_events(ev_ids):
             return self.get_events(
                 ev_ids, get_prev_content=False, check_redacted=False,
             )
+
+        state_groups = {
+            sg: state_groups_map[sg] for sg in new_state_groups
+        }
+
         events_map = {ev.event_id: ev for ev, _ in events_context}
         logger.debug("calling resolve_state_groups from preserve_events")
         res = yield self._state_resolution_handler.resolve_state_groups(

synapse/storage/events_worker.py

@@ -20,7 +20,7 @@ from synapse.events import FrozenEvent
 from synapse.events.utils import prune_event
 
 from synapse.util.logcontext import (
-    preserve_fn, PreserveLoggingContext, make_deferred_yieldable
+    PreserveLoggingContext, make_deferred_yieldable, run_in_background,
 )
 from synapse.util.metrics import Measure
 from synapse.api.errors import SynapseError
@@ -319,7 +319,8 @@ class EventsWorkerStore(SQLBaseStore):
 
         res = yield make_deferred_yieldable(defer.gatherResults(
             [
-                preserve_fn(self._get_event_from_row)(
+                run_in_background(
+                    self._get_event_from_row,
                     row["internal_metadata"], row["json"], row["redacts"],
                     rejected_reason=row["rejects"],
                 )

synapse/storage/registration.py

@@ -22,6 +22,8 @@ from synapse.storage import background_updates
 from synapse.storage._base import SQLBaseStore
 from synapse.util.caches.descriptors import cached, cachedInlineCallbacks
 
+from six.moves import range
+
 
 class RegistrationWorkerStore(SQLBaseStore):
     @cached()
@@ -469,7 +471,7 @@ class RegistrationStore(RegistrationWorkerStore,
                 match = regex.search(user_id)
                 if match:
                     found.add(int(match.group(1)))
-            for i in xrange(len(found) + 1):
+            for i in range(len(found) + 1):
                 if i not in found:
                     return i
 

synapse/storage/room.py

@@ -530,7 +530,7 @@ class RoomStore(RoomWorkerStore, SearchStore):
 
             # Convert the IDs to MXC URIs
             for media_id in local_mxcs:
-                local_media_mxcs.append("mxc://%s/%s" % (self.hostname, media_id))
+                local_media_mxcs.append("mxc://%s/%s" % (self.hs.hostname, media_id))
             for hostname, media_id in remote_mxcs:
                 remote_media_mxcs.append("mxc://%s/%s" % (hostname, media_id))
 
@@ -595,7 +595,7 @@ class RoomStore(RoomWorkerStore, SearchStore):
         while next_token:
             sql = """
                 SELECT stream_ordering, json FROM events
-                JOIN event_json USING (event_id)
+                JOIN event_json USING (room_id, event_id)
                 WHERE room_id = ?
                     AND stream_ordering < ?
                     AND contains_url = ? AND outlier = ?
@@ -619,7 +619,7 @@ class RoomStore(RoomWorkerStore, SearchStore):
                     if matches:
                         hostname = matches.group(1)
                         media_id = matches.group(2)
-                        if hostname == self.hostname:
+                        if hostname == self.hs.hostname:
                             local_media_mxcs.append(media_id)
                         else:
                             remote_media_mxcs.append((hostname, media_id))

synapse/storage/schema/delta/30/as_users.py

@@ -14,6 +14,8 @@
 import logging
 from synapse.config.appservice import load_appservices
 
+from six.moves import range
+
 
 logger = logging.getLogger(__name__)
 
@@ -58,7 +60,7 @@ def run_upgrade(cur, database_engine, config, *args, **kwargs):
 
     for as_id, user_ids in owned.items():
         n = 100
-        user_chunks = (user_ids[i:i + 100] for i in xrange(0, len(user_ids), n))
+        user_chunks = (user_ids[i:i + 100] for i in range(0, len(user_ids), n))
         for chunk in user_chunks:
             cur.execute(
                 database_engine.convert_param_style(

synapse/storage/schema/delta/48/group_unique_indexes.py

@@ -0,0 +1,57 @@
+# Copyright 2018 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# 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.
+
+from synapse.storage.engines import PostgresEngine
+from synapse.storage.prepare_database import get_statements
+
+FIX_INDEXES = """
+-- rebuild indexes as uniques
+DROP INDEX groups_invites_g_idx;
+CREATE UNIQUE INDEX group_invites_g_idx ON group_invites(group_id, user_id);
+DROP INDEX groups_users_g_idx;
+CREATE UNIQUE INDEX group_users_g_idx ON group_users(group_id, user_id);
+
+-- rename other indexes to actually match their table names..
+DROP INDEX groups_users_u_idx;
+CREATE INDEX group_users_u_idx ON group_users(user_id);
+DROP INDEX groups_invites_u_idx;
+CREATE INDEX group_invites_u_idx ON group_invites(user_id);
+DROP INDEX groups_rooms_g_idx;
+CREATE UNIQUE INDEX group_rooms_g_idx ON group_rooms(group_id, room_id);
+DROP INDEX groups_rooms_r_idx;
+CREATE INDEX group_rooms_r_idx ON group_rooms(room_id);
+"""
+
+
+def run_create(cur, database_engine, *args, **kwargs):
+    rowid = "ctid" if isinstance(database_engine, PostgresEngine) else "rowid"
+
+    # remove duplicates from group_users & group_invites tables
+    cur.execute("""
+        DELETE FROM group_users WHERE %s NOT IN (
+           SELECT min(%s) FROM group_users GROUP BY group_id, user_id
+        );
+    """ % (rowid, rowid))
+    cur.execute("""
+        DELETE FROM group_invites WHERE %s NOT IN (
+           SELECT min(%s) FROM group_invites GROUP BY group_id, user_id
+        );
+    """ % (rowid, rowid))
+
+    for statement in get_statements(FIX_INDEXES.splitlines()):
+        cur.execute(statement)
+
+
+def run_upgrade(*args, **kwargs):
+    pass

synapse/storage/search.py

@@ -77,7 +77,7 @@ class SearchStore(BackgroundUpdateStore):
             sql = (
                 "SELECT stream_ordering, event_id, room_id, type, json, "
                 " origin_server_ts FROM events"
-                " JOIN event_json USING (event_id)"
+                " JOIN event_json USING (room_id, event_id)"
                 " WHERE ? <= stream_ordering AND stream_ordering < ?"
                 " AND (%s)"
                 " ORDER BY stream_ordering DESC"

synapse/storage/stream.py

@@ -38,15 +38,17 @@ from twisted.internet import defer
 from synapse.storage._base import SQLBaseStore
 from synapse.storage.events import EventsWorkerStore
 
-from synapse.util.caches.descriptors import cached
 from synapse.types import RoomStreamToken
 from synapse.util.caches.stream_change_cache import StreamChangeCache
-from synapse.util.logcontext import make_deferred_yieldable, preserve_fn
-from synapse.storage.engines import PostgresEngine, Sqlite3Engine
+from synapse.util.logcontext import make_deferred_yieldable, run_in_background
+from synapse.storage.engines import PostgresEngine
 
 import abc
 import logging
 
+from six.moves import range
+from collections import namedtuple
+
 
 logger = logging.getLogger(__name__)
 
@@ -58,6 +60,12 @@ _STREAM_TOKEN = "stream"
 _TOPOLOGICAL_TOKEN = "topological"
 
 
+# Used as return values for pagination APIs
+_EventDictReturn = namedtuple("_EventDictReturn", (
+    "event_id", "topological_ordering", "stream_ordering",
+))
+
+
 def lower_bound(token, engine, inclusive=False):
     inclusive = "=" if inclusive else ""
     if token.topological is None:
@@ -196,13 +204,14 @@ class StreamWorkerStore(EventsWorkerStore, SQLBaseStore):
 
         results = {}
         room_ids = list(room_ids)
-        for rm_ids in (room_ids[i:i + 20] for i in xrange(0, len(room_ids), 20)):
+        for rm_ids in (room_ids[i:i + 20] for i in range(0, len(room_ids), 20)):
             res = yield make_deferred_yieldable(defer.gatherResults([
-                preserve_fn(self.get_room_events_stream_for_room)(
+                run_in_background(
+                    self.get_room_events_stream_for_room,
                     room_id, from_key, to_key, limit, order=order,
                 )
                 for room_id in rm_ids
-            ]))
+            ], consumeErrors=True))
             results.update(dict(zip(rm_ids, res)))
 
         defer.returnValue(results)
@@ -224,54 +233,55 @@ class StreamWorkerStore(EventsWorkerStore, SQLBaseStore):
     @defer.inlineCallbacks
     def get_room_events_stream_for_room(self, room_id, from_key, to_key, limit=0,
                                         order='DESC'):
-        # Note: If from_key is None then we return in topological order. This
-        # is because in that case we're using this as a "get the last few messages
-        # in a room" function, rather than "get new messages since last sync"
-        if from_key is not None:
-            from_id = RoomStreamToken.parse_stream_token(from_key).stream
-        else:
-            from_id = None
-        to_id = RoomStreamToken.parse_stream_token(to_key).stream
 
+        """Get new room events in stream ordering since `from_key`.
+
+        Args:
+            room_id (str)
+            from_key (str): Token from which no events are returned before
+            to_key (str): Token from which no events are returned after. (This
+                is typically the current stream token)
+            limit (int): Maximum number of events to return
+            order (str): Either "DESC" or "ASC". Determines which events are
+                returned when the result is limited. If "DESC" then the most
+                recent `limit` events are returned, otherwise returns the
+                oldest `limit` events.
+
+        Returns:
+            Deferred[tuple[list[FrozenEvent], str]]: Returns the list of
+            events (in ascending order) and the token from the start of
+            the chunk of events returned.
+        """
         if from_key == to_key:
             defer.returnValue(([], from_key))
 
-        if from_id:
-            has_changed = yield self._events_stream_cache.has_entity_changed(
-                room_id, from_id
-            )
+        from_id = RoomStreamToken.parse_stream_token(from_key).stream
+        to_id = RoomStreamToken.parse_stream_token(to_key).stream
 
-            if not has_changed:
-                defer.returnValue(([], from_key))
+        has_changed = yield self._events_stream_cache.has_entity_changed(
+            room_id, from_id
+        )
+
+        if not has_changed:
+            defer.returnValue(([], from_key))
 
         def f(txn):
-            if from_id is not None:
-                sql = (
-                    "SELECT event_id, stream_ordering FROM events WHERE"
-                    " room_id = ?"
-                    " AND not outlier"
-                    " AND stream_ordering > ? AND stream_ordering <= ?"
-                    " ORDER BY stream_ordering %s LIMIT ?"
-                ) % (order,)
-                txn.execute(sql, (room_id, from_id, to_id, limit))
-            else:
-                sql = (
-                    "SELECT event_id, stream_ordering FROM events WHERE"
-                    " room_id = ?"
-                    " AND not outlier"
-                    " AND stream_ordering <= ?"
-                    " ORDER BY topological_ordering %s, stream_ordering %s LIMIT ?"
-                ) % (order, order,)
-                txn.execute(sql, (room_id, to_id, limit))
-
-            rows = self.cursor_to_dict(txn)
+            sql = (
+                "SELECT event_id, stream_ordering FROM events WHERE"
+                " room_id = ?"
+                " AND not outlier"
+                " AND stream_ordering > ? AND stream_ordering <= ?"
+                " ORDER BY stream_ordering %s LIMIT ?"
+            ) % (order,)
+            txn.execute(sql, (room_id, from_id, to_id, limit))
 
+            rows = [_EventDictReturn(row[0], None, row[1]) for row in txn]
             return rows
 
         rows = yield self.runInteraction("get_room_events_stream_for_room", f)
 
         ret = yield self._get_events(
-            [r["event_id"] for r in rows],
+            [r.event_id for r in rows],
             get_prev_content=True
         )
 
@@ -281,7 +291,7 @@ class StreamWorkerStore(EventsWorkerStore, SQLBaseStore):
             ret.reverse()
 
         if rows:
-            key = "s%d" % min(r["stream_ordering"] for r in rows)
+            key = "s%d" % min(r.stream_ordering for r in rows)
         else:
             # Assume we didn't get anything because there was nothing to
             # get.
@@ -291,10 +301,7 @@ class StreamWorkerStore(EventsWorkerStore, SQLBaseStore):
 
     @defer.inlineCallbacks
     def get_membership_changes_for_user(self, user_id, from_key, to_key):
-        if from_key is not None:
-            from_id = RoomStreamToken.parse_stream_token(from_key).stream
-        else:
-            from_id = None
+        from_id = RoomStreamToken.parse_stream_token(from_key).stream
         to_id = RoomStreamToken.parse_stream_token(to_key).stream
 
         if from_key == to_key:
@@ -308,34 +315,24 @@ class StreamWorkerStore(EventsWorkerStore, SQLBaseStore):
                 defer.returnValue([])
 
         def f(txn):
-            if from_id is not None:
-                sql = (
-                    "SELECT m.event_id, stream_ordering FROM events AS e,"
-                    " room_memberships AS m"
-                    " WHERE e.event_id = m.event_id"
-                    " AND m.user_id = ?"
-                    " AND e.stream_ordering > ? AND e.stream_ordering <= ?"
-                    " ORDER BY e.stream_ordering ASC"
-                )
-                txn.execute(sql, (user_id, from_id, to_id,))
-            else:
-                sql = (
-                    "SELECT m.event_id, stream_ordering FROM events AS e,"
-                    " room_memberships AS m"
-                    " WHERE e.event_id = m.event_id"
-                    " AND m.user_id = ?"
-                    " AND stream_ordering <= ?"
-                    " ORDER BY stream_ordering ASC"
-                )
-                txn.execute(sql, (user_id, to_id,))
-            rows = self.cursor_to_dict(txn)
+            sql = (
+                "SELECT m.event_id, stream_ordering FROM events AS e,"
+                " room_memberships AS m"
+                " WHERE e.event_id = m.event_id"
+                " AND m.user_id = ?"
+                " AND e.stream_ordering > ? AND e.stream_ordering <= ?"
+                " ORDER BY e.stream_ordering ASC"
+            )
+            txn.execute(sql, (user_id, from_id, to_id,))
+
+            rows = [_EventDictReturn(row[0], None, row[1]) for row in txn]
 
             return rows
 
         rows = yield self.runInteraction("get_membership_changes_for_user", f)
 
         ret = yield self._get_events(
-            [r["event_id"] for r in rows],
+            [r.event_id for r in rows],
             get_prev_content=True
         )
 
@@ -344,14 +341,28 @@ class StreamWorkerStore(EventsWorkerStore, SQLBaseStore):
         defer.returnValue(ret)
 
     @defer.inlineCallbacks
-    def get_recent_events_for_room(self, room_id, limit, end_token, from_token=None):
+    def get_recent_events_for_room(self, room_id, limit, end_token):
+        """Get the most recent events in the room in topological ordering.
+
+        Args:
+            room_id (str)
+            limit (int)
+            end_token (str): The stream token representing now.
+
+        Returns:
+            Deferred[tuple[list[FrozenEvent],  str]]: Returns a list of
+            events and a token pointing to the start of the returned
+            events.
+            The events returned are in ascending order.
+        """
+
         rows, token = yield self.get_recent_event_ids_for_room(
-            room_id, limit, end_token, from_token
+            room_id, limit, end_token,
         )
 
         logger.debug("stream before")
         events = yield self._get_events(
-            [r["event_id"] for r in rows],
+            [r.event_id for r in rows],
             get_prev_content=True
         )
         logger.debug("stream after")
@@ -360,61 +371,37 @@ class StreamWorkerStore(EventsWorkerStore, SQLBaseStore):
 
         defer.returnValue((events, token))
 
-    @cached(num_args=4)
-    def get_recent_event_ids_for_room(self, room_id, limit, end_token, from_token=None):
-        end_token = RoomStreamToken.parse_stream_token(end_token)
+    @defer.inlineCallbacks
+    def get_recent_event_ids_for_room(self, room_id, limit, end_token):
+        """Get the most recent events in the room in topological ordering.
 
-        if from_token is None:
-            sql = (
-                "SELECT stream_ordering, topological_ordering, event_id"
-                " FROM events"
-                " WHERE room_id = ? AND stream_ordering <= ? AND outlier = ?"
-                " ORDER BY topological_ordering DESC, stream_ordering DESC"
-                " LIMIT ?"
-            )
-        else:
-            from_token = RoomStreamToken.parse_stream_token(from_token)
-            sql = (
-                "SELECT stream_ordering, topological_ordering, event_id"
-                " FROM events"
-                " WHERE room_id = ? AND stream_ordering > ?"
-                " AND stream_ordering <= ? AND outlier = ?"
-                " ORDER BY topological_ordering DESC, stream_ordering DESC"
-                " LIMIT ?"
-            )
+        Args:
+            room_id (str)
+            limit (int)
+            end_token (str): The stream token representing now.
 
-        def get_recent_events_for_room_txn(txn):
-            if from_token is None:
-                txn.execute(sql, (room_id, end_token.stream, False, limit,))
-            else:
-                txn.execute(sql, (
-                    room_id, from_token.stream, end_token.stream, False, limit
-                ))
+        Returns:
+            Deferred[tuple[list[_EventDictReturn],  str]]: Returns a list of
+            _EventDictReturn and a token pointing to the start of the returned
+            events.
+            The events returned are in ascending order.
+        """
+        # Allow a zero limit here, and no-op.
+        if limit == 0:
+            defer.returnValue(([], end_token))
 
-            rows = self.cursor_to_dict(txn)
+        end_token = RoomStreamToken.parse(end_token)
 
-            rows.reverse()  # As we selected with reverse ordering
-
-            if rows:
-                # Tokens are positions between events.
-                # This token points *after* the last event in the chunk.
-                # We need it to point to the event before it in the chunk
-                # since we are going backwards so we subtract one from the
-                # stream part.
-                topo = rows[0]["topological_ordering"]
-                toke = rows[0]["stream_ordering"] - 1
-                start_token = str(RoomStreamToken(topo, toke))
-
-                token = (start_token, str(end_token))
-            else:
-                token = (str(end_token), str(end_token))
-
-            return rows, token
-
-        return self.runInteraction(
-            "get_recent_events_for_room", get_recent_events_for_room_txn
+        rows, token = yield self.runInteraction(
+            "get_recent_event_ids_for_room", self._paginate_room_events_txn,
+            room_id, from_token=end_token, limit=limit,
         )
 
+        # We want to return the results in ascending order.
+        rows.reverse()
+
+        defer.returnValue((rows, token))
+
     def get_room_event_after_stream_ordering(self, room_id, stream_ordering):
         """Gets details of the first event in a room at or after a stream ordering
 
@@ -517,10 +504,20 @@ class StreamWorkerStore(EventsWorkerStore, SQLBaseStore):
 
     @staticmethod
     def _set_before_and_after(events, rows, topo_order=True):
+        """Inserts ordering information to events' internal metadata from
+        the DB rows.
+
+        Args:
+            events (list[FrozenEvent])
+            rows (list[_EventDictReturn])
+            topo_order (bool): Whether the events were ordered topologically
+                or by stream ordering. If true then all rows should have a non
+                null topological_ordering.
+        """
         for event, row in zip(events, rows):
-            stream = row["stream_ordering"]
-            if topo_order:
-                topo = event.depth
+            stream = row.stream_ordering
+            if topo_order and row.topological_ordering:
+                topo = row.topological_ordering
             else:
                 topo = None
             internal = event.internal_metadata
@@ -592,87 +589,27 @@ class StreamWorkerStore(EventsWorkerStore, SQLBaseStore):
             retcols=["stream_ordering", "topological_ordering"],
         )
 
-        token = RoomStreamToken(
+        # Paginating backwards includes the event at the token, but paginating
+        # forward doesn't.
+        before_token = RoomStreamToken(
+            results["topological_ordering"] - 1,
+            results["stream_ordering"],
+        )
+
+        after_token = RoomStreamToken(
             results["topological_ordering"],
             results["stream_ordering"],
         )
 
-        if isinstance(self.database_engine, Sqlite3Engine):
-            # SQLite3 doesn't optimise ``(x < a) OR (x = a AND y < b)``
-            # So we give pass it to SQLite3 as the UNION ALL of the two queries.
+        rows, start_token = self._paginate_room_events_txn(
+            txn, room_id, before_token, direction='b', limit=before_limit,
+        )
+        events_before = [r.event_id for r in rows]
 
-            query_before = (
-                "SELECT topological_ordering, stream_ordering, event_id FROM events"
-                " WHERE room_id = ? AND topological_ordering < ?"
-                " UNION ALL"
-                " SELECT topological_ordering, stream_ordering, event_id FROM events"
-                " WHERE room_id = ? AND topological_ordering = ? AND stream_ordering < ?"
-                " ORDER BY topological_ordering DESC, stream_ordering DESC LIMIT ?"
-            )
-            before_args = (
-                room_id, token.topological,
-                room_id, token.topological, token.stream,
-                before_limit,
-            )
-
-            query_after = (
-                "SELECT topological_ordering, stream_ordering, event_id FROM events"
-                " WHERE room_id = ? AND topological_ordering > ?"
-                " UNION ALL"
-                " SELECT topological_ordering, stream_ordering, event_id FROM events"
-                " WHERE room_id = ? AND topological_ordering = ? AND stream_ordering > ?"
-                " ORDER BY topological_ordering ASC, stream_ordering ASC LIMIT ?"
-            )
-            after_args = (
-                room_id, token.topological,
-                room_id, token.topological, token.stream,
-                after_limit,
-            )
-        else:
-            query_before = (
-                "SELECT topological_ordering, stream_ordering, event_id FROM events"
-                " WHERE room_id = ? AND %s"
-                " ORDER BY topological_ordering DESC, stream_ordering DESC LIMIT ?"
-            ) % (upper_bound(token, self.database_engine, inclusive=False),)
-
-            before_args = (room_id, before_limit)
-
-            query_after = (
-                "SELECT topological_ordering, stream_ordering, event_id FROM events"
-                " WHERE room_id = ? AND %s"
-                " ORDER BY topological_ordering ASC, stream_ordering ASC LIMIT ?"
-            ) % (lower_bound(token, self.database_engine, inclusive=False),)
-
-            after_args = (room_id, after_limit)
-
-        txn.execute(query_before, before_args)
-
-        rows = self.cursor_to_dict(txn)
-        events_before = [r["event_id"] for r in rows]
-
-        if rows:
-            start_token = str(RoomStreamToken(
-                rows[0]["topological_ordering"],
-                rows[0]["stream_ordering"] - 1,
-            ))
-        else:
-            start_token = str(RoomStreamToken(
-                token.topological,
-                token.stream - 1,
-            ))
-
-        txn.execute(query_after, after_args)
-
-        rows = self.cursor_to_dict(txn)
-        events_after = [r["event_id"] for r in rows]
-
-        if rows:
-            end_token = str(RoomStreamToken(
-                rows[-1]["topological_ordering"],
-                rows[-1]["stream_ordering"],
-            ))
-        else:
-            end_token = str(token)
+        rows, end_token = self._paginate_room_events_txn(
+            txn, room_id, after_token, direction='f', limit=after_limit,
+        )
+        events_after = [r.event_id for r in rows]
 
         return {
             "before": {
@@ -735,17 +672,28 @@ class StreamWorkerStore(EventsWorkerStore, SQLBaseStore):
     def has_room_changed_since(self, room_id, stream_id):
         return self._events_stream_cache.has_entity_changed(room_id, stream_id)
 
+    def _paginate_room_events_txn(self, txn, room_id, from_token, to_token=None,
+                                  direction='b', limit=-1, event_filter=None):
+        """Returns list of events before or after a given token.
 
-class StreamStore(StreamWorkerStore):
-    def get_room_max_stream_ordering(self):
-        return self._stream_id_gen.get_current_token()
+        Args:
+            txn
+            room_id (str)
+            from_token (RoomStreamToken): The token used to stream from
+            to_token (RoomStreamToken|None): A token which if given limits the
+                results to only those before
+            direction(char): Either 'b' or 'f' to indicate whether we are
+                paginating forwards or backwards from `from_key`.
+            limit (int): The maximum number of events to return. Zero or less
+                means no limit.
+            event_filter (Filter|None): If provided filters the events to
+                those that match the filter.
 
-    def get_room_min_stream_ordering(self):
-        return self._backfill_id_gen.get_current_token()
-
-    @defer.inlineCallbacks
-    def paginate_room_events(self, room_id, from_key, to_key=None,
-                             direction='b', limit=-1, event_filter=None):
+        Returns:
+            Deferred[tuple[list[_EventDictReturn], str]]: Returns the results
+            as a list of _EventDictReturn and a token that points to the end
+            of the result set.
+        """
         # Tokens really represent positions between elements, but we use
         # the convention of pointing to the event before the gap. Hence
         # we have a bit of asymmetry when it comes to equalities.
@@ -753,20 +701,20 @@ class StreamStore(StreamWorkerStore):
         if direction == 'b':
             order = "DESC"
             bounds = upper_bound(
-                RoomStreamToken.parse(from_key), self.database_engine
+                from_token, self.database_engine
             )
-            if to_key:
+            if to_token:
                 bounds = "%s AND %s" % (bounds, lower_bound(
-                    RoomStreamToken.parse(to_key), self.database_engine
+                    to_token, self.database_engine
                 ))
         else:
             order = "ASC"
             bounds = lower_bound(
-                RoomStreamToken.parse(from_key), self.database_engine
+                from_token, self.database_engine
             )
-            if to_key:
+            if to_token:
                 bounds = "%s AND %s" % (bounds, upper_bound(
-                    RoomStreamToken.parse(to_key), self.database_engine
+                    to_token, self.database_engine
                 ))
 
         filter_clause, filter_args = filter_to_clause(event_filter)
@@ -782,7 +730,8 @@ class StreamStore(StreamWorkerStore):
             limit_str = ""
 
         sql = (
-            "SELECT * FROM events"
+            "SELECT event_id, topological_ordering, stream_ordering"
+            " FROM events"
             " WHERE outlier = ? AND room_id = ? AND %(bounds)s"
             " ORDER BY topological_ordering %(order)s,"
             " stream_ordering %(order)s %(limit)s"
@@ -792,35 +741,72 @@ class StreamStore(StreamWorkerStore):
             "limit": limit_str
         }
 
-        def f(txn):
-            txn.execute(sql, args)
+        txn.execute(sql, args)
 
-            rows = self.cursor_to_dict(txn)
+        rows = [_EventDictReturn(row[0], row[1], row[2]) for row in txn]
 
-            if rows:
-                topo = rows[-1]["topological_ordering"]
-                toke = rows[-1]["stream_ordering"]
-                if direction == 'b':
-                    # Tokens are positions between events.
-                    # This token points *after* the last event in the chunk.
-                    # We need it to point to the event before it in the chunk
-                    # when we are going backwards so we subtract one from the
-                    # stream part.
-                    toke -= 1
-                next_token = str(RoomStreamToken(topo, toke))
-            else:
-                # TODO (erikj): We should work out what to do here instead.
-                next_token = to_key if to_key else from_key
+        if rows:
+            topo = rows[-1].topological_ordering
+            toke = rows[-1].stream_ordering
+            if direction == 'b':
+                # Tokens are positions between events.
+                # This token points *after* the last event in the chunk.
+                # We need it to point to the event before it in the chunk
+                # when we are going backwards so we subtract one from the
+                # stream part.
+                toke -= 1
+            next_token = RoomStreamToken(topo, toke)
+        else:
+            # TODO (erikj): We should work out what to do here instead.
+            next_token = to_token if to_token else from_token
 
-            return rows, next_token,
+        return rows, str(next_token),
 
-        rows, token = yield self.runInteraction("paginate_room_events", f)
+    @defer.inlineCallbacks
+    def paginate_room_events(self, room_id, from_key, to_key=None,
+                             direction='b', limit=-1, event_filter=None):
+        """Returns list of events before or after a given token.
+
+        Args:
+            room_id (str)
+            from_key (str): The token used to stream from
+            to_key (str|None): A token which if given limits the results to
+                only those before
+            direction(char): Either 'b' or 'f' to indicate whether we are
+                paginating forwards or backwards from `from_key`.
+            limit (int): The maximum number of events to return. Zero or less
+                means no limit.
+            event_filter (Filter|None): If provided filters the events to
+                those that match the filter.
+
+        Returns:
+            tuple[list[dict], str]: Returns the results as a list of dicts and
+            a token that points to the end of the result set. The dicts have
+            the keys "event_id", "topological_ordering" and "stream_orderign".
+        """
+
+        from_key = RoomStreamToken.parse(from_key)
+        if to_key:
+            to_key = RoomStreamToken.parse(to_key)
+
+        rows, token = yield self.runInteraction(
+            "paginate_room_events", self._paginate_room_events_txn,
+            room_id, from_key, to_key, direction, limit, event_filter,
+        )
 
         events = yield self._get_events(
-            [r["event_id"] for r in rows],
+            [r.event_id for r in rows],
             get_prev_content=True
         )
 
         self._set_before_and_after(events, rows)
 
         defer.returnValue((events, token))
+
+
+class StreamStore(StreamWorkerStore):
+    def get_room_max_stream_ordering(self):
+        return self._stream_id_gen.get_current_token()
+
+    def get_room_min_stream_ordering(self):
+        return self._backfill_id_gen.get_current_token()

synapse/storage/tags.py

@@ -22,6 +22,8 @@ from twisted.internet import defer
 import simplejson as json
 import logging
 
+from six.moves import range
+
 logger = logging.getLogger(__name__)
 
 
@@ -98,7 +100,7 @@ class TagsWorkerStore(AccountDataWorkerStore):
 
         batch_size = 50
         results = []
-        for i in xrange(0, len(tag_ids), batch_size):
+        for i in range(0, len(tag_ids), batch_size):
             tags = yield self.runInteraction(
                 "get_all_updated_tag_content",
                 get_tag_content,

synapse/util/__init__.py

@@ -13,7 +13,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from synapse.api.errors import SynapseError
 from synapse.util.logcontext import PreserveLoggingContext
 
 from twisted.internet import defer, reactor, task
@@ -24,11 +23,6 @@ import logging
 logger = logging.getLogger(__name__)
 
 
-class DeferredTimedOutError(SynapseError):
-    def __init__(self):
-        super(DeferredTimedOutError, self).__init__(504, "Timed out")
-
-
 def unwrapFirstError(failure):
     # defer.gatherResults and DeferredLists wrap failures.
     failure.trap(defer.FirstError)
@@ -85,53 +79,3 @@ class Clock(object):
         except Exception:
             if not ignore_errs:
                 raise
-
-    def time_bound_deferred(self, given_deferred, time_out):
-        if given_deferred.called:
-            return given_deferred
-
-        ret_deferred = defer.Deferred()
-
-        def timed_out_fn():
-            e = DeferredTimedOutError()
-
-            try:
-                ret_deferred.errback(e)
-            except Exception:
-                pass
-
-            try:
-                given_deferred.cancel()
-            except Exception:
-                pass
-
-        timer = None
-
-        def cancel(res):
-            try:
-                self.cancel_call_later(timer)
-            except Exception:
-                pass
-            return res
-
-        ret_deferred.addBoth(cancel)
-
-        def success(res):
-            try:
-                ret_deferred.callback(res)
-            except Exception:
-                pass
-
-            return res
-
-        def err(res):
-            try:
-                ret_deferred.errback(res)
-            except Exception:
-                pass
-
-        given_deferred.addCallbacks(callback=success, errback=err)
-
-        timer = self.call_later(time_out, timed_out_fn)
-
-        return ret_deferred

synapse/util/async.py

@@ -15,9 +15,11 @@
 
 
 from twisted.internet import defer, reactor
+from twisted.internet.defer import CancelledError
+from twisted.python import failure
 
 from .logcontext import (
-    PreserveLoggingContext, make_deferred_yieldable, preserve_fn
+    PreserveLoggingContext, make_deferred_yieldable, run_in_background
 )
 from synapse.util import logcontext, unwrapFirstError
 
@@ -25,6 +27,8 @@ from contextlib import contextmanager
 
 import logging
 
+from six.moves import range
+
 logger = logging.getLogger(__name__)
 
 
@@ -156,13 +160,13 @@ def concurrently_execute(func, args, limit):
     def _concurrently_execute_inner():
         try:
             while True:
-                yield func(it.next())
+                yield func(next(it))
         except StopIteration:
             pass
 
     return logcontext.make_deferred_yieldable(defer.gatherResults([
-        preserve_fn(_concurrently_execute_inner)()
-        for _ in xrange(limit)
+        run_in_background(_concurrently_execute_inner)
+        for _ in range(limit)
     ], consumeErrors=True)).addErrback(unwrapFirstError)
 
 
@@ -392,3 +396,68 @@ class ReadWriteLock(object):
                     self.key_to_current_writer.pop(key)
 
         defer.returnValue(_ctx_manager())
+
+
+class DeferredTimeoutError(Exception):
+    """
+    This error is raised by default when a L{Deferred} times out.
+    """
+
+
+def add_timeout_to_deferred(deferred, timeout, on_timeout_cancel=None):
+    """
+    Add a timeout to a deferred by scheduling it to be cancelled after
+    timeout seconds.
+
+    This is essentially a backport of deferred.addTimeout, which was introduced
+    in twisted 16.5.
+
+    If the deferred gets timed out, it errbacks with a DeferredTimeoutError,
+    unless a cancelable function was passed to its initialization or unless
+    a different on_timeout_cancel callable is provided.
+
+    Args:
+        deferred (defer.Deferred): deferred to be timed out
+        timeout (Number): seconds to time out after
+
+        on_timeout_cancel (callable): A callable which is called immediately
+            after the deferred times out, and not if this deferred is
+            otherwise cancelled before the timeout.
+
+            It takes an arbitrary value, which is the value of the deferred at
+            that exact point in time (probably a CancelledError Failure), and
+            the timeout.
+
+            The default callable (if none is provided) will translate a
+            CancelledError Failure into a DeferredTimeoutError.
+    """
+    timed_out = [False]
+
+    def time_it_out():
+        timed_out[0] = True
+        deferred.cancel()
+
+    delayed_call = reactor.callLater(timeout, time_it_out)
+
+    def convert_cancelled(value):
+        if timed_out[0]:
+            to_call = on_timeout_cancel or _cancelled_to_timed_out_error
+            return to_call(value, timeout)
+        return value
+
+    deferred.addBoth(convert_cancelled)
+
+    def cancel_timeout(result):
+        # stop the pending call to cancel the deferred if it's been fired
+        if delayed_call.active():
+            delayed_call.cancel()
+        return result
+
+    deferred.addBoth(cancel_timeout)
+
+
+def _cancelled_to_timed_out_error(value, timeout):
+    if isinstance(value, failure.Failure):
+        value.trap(CancelledError)
+        raise DeferredTimeoutError(timeout, "Deferred")
+    return value

synapse/util/file_consumer.py

@@ -15,7 +15,7 @@
 
 from twisted.internet import threads, reactor
 
-from synapse.util.logcontext import make_deferred_yieldable, preserve_fn
+from synapse.util.logcontext import make_deferred_yieldable, run_in_background
 
 from six.moves import queue
 
@@ -70,7 +70,9 @@ class BackgroundFileConsumer(object):
 
         self._producer = producer
         self.streaming = streaming
-        self._finished_deferred = preserve_fn(threads.deferToThread)(self._writer)
+        self._finished_deferred = run_in_background(
+            threads.deferToThread, self._writer
+        )
         if not streaming:
             self._producer.resumeProducing()
 

synapse/util/httpresourcetree.py

@@ -40,9 +40,12 @@ def create_resource_tree(desired_tree, root_resource):
     # extra resources to existing nodes. See self._resource_id for the key.
     resource_mappings = {}
     for full_path, res in desired_tree.items():
+        # twisted requires all resources to be bytes
+        full_path = full_path.encode("utf-8")
+
         logger.info("Attaching %s to path %s", res, full_path)
         last_resource = root_resource
-        for path_seg in full_path.split('/')[1:-1]:
+        for path_seg in full_path.split(b'/')[1:-1]:
             if path_seg not in last_resource.listNames():
                 # resource doesn't exist, so make a "dummy resource"
                 child_resource = NoResource()
@@ -57,7 +60,7 @@ def create_resource_tree(desired_tree, root_resource):
 
         # ===========================
         # now attach the actual desired resource
-        last_path_seg = full_path.split('/')[-1]
+        last_path_seg = full_path.split(b'/')[-1]
 
         # if there is already a resource here, thieve its children and
         # replace it

synapse/util/logcontext.py

@@ -164,7 +164,7 @@ class LoggingContext(object):
         current = self.set_current_context(self.previous_context)
         if current is not self:
             if current is self.sentinel:
-                logger.debug("Expected logging context %s has been lost", self)
+                logger.warn("Expected logging context %s has been lost", self)
             else:
                 logger.warn(
                     "Current logging context %s is not expected context %s",
@@ -279,7 +279,7 @@ class PreserveLoggingContext(object):
         context = LoggingContext.set_current_context(self.current_context)
 
         if context != self.new_context:
-            logger.debug(
+            logger.warn(
                 "Unexpected logging context: %s is not %s",
                 context, self.new_context,
             )
@@ -302,31 +302,49 @@ def preserve_fn(f):
 def run_in_background(f, *args, **kwargs):
     """Calls a function, ensuring that the current context is restored after
     return from the function, and that the sentinel context is set once the
-    deferred returned by the funtion completes.
+    deferred returned by the function completes.
 
     Useful for wrapping functions that return a deferred which you don't yield
-    on.
+    on (for instance because you want to pass it to deferred.gatherResults()).
+
+    Note that if you completely discard the result, you should make sure that
+    `f` doesn't raise any deferred exceptions, otherwise a scary-looking
+    CRITICAL error about an unhandled error will be logged without much
+    indication about where it came from.
     """
     current = LoggingContext.current_context()
-    res = f(*args, **kwargs)
-    if isinstance(res, defer.Deferred) and not res.called:
-        # The function will have reset the context before returning, so
-        # we need to restore it now.
-        LoggingContext.set_current_context(current)
+    try:
+        res = f(*args, **kwargs)
+    except:   # noqa: E722
+        # the assumption here is that the caller doesn't want to be disturbed
+        # by synchronous exceptions, so let's turn them into Failures.
+        return defer.fail()
 
-        # The original context will be restored when the deferred
-        # completes, but there is nothing waiting for it, so it will
-        # get leaked into the reactor or some other function which
-        # wasn't expecting it. We therefore need to reset the context
-        # here.
-        #
-        # (If this feels asymmetric, consider it this way: we are
-        # effectively forking a new thread of execution. We are
-        # probably currently within a ``with LoggingContext()`` block,
-        # which is supposed to have a single entry and exit point. But
-        # by spawning off another deferred, we are effectively
-        # adding a new exit point.)
-        res.addBoth(_set_context_cb, LoggingContext.sentinel)
+    if not isinstance(res, defer.Deferred):
+        return res
+
+    if res.called and not res.paused:
+        # The function should have maintained the logcontext, so we can
+        # optimise out the messing about
+        return res
+
+    # The function may have reset the context before returning, so
+    # we need to restore it now.
+    ctx = LoggingContext.set_current_context(current)
+
+    # The original context will be restored when the deferred
+    # completes, but there is nothing waiting for it, so it will
+    # get leaked into the reactor or some other function which
+    # wasn't expecting it. We therefore need to reset the context
+    # here.
+    #
+    # (If this feels asymmetric, consider it this way: we are
+    # effectively forking a new thread of execution. We are
+    # probably currently within a ``with LoggingContext()`` block,
+    # which is supposed to have a single entry and exit point. But
+    # by spawning off another deferred, we are effectively
+    # adding a new exit point.)
+    res.addBoth(_set_context_cb, ctx)
     return res
 
 
@@ -341,11 +359,20 @@ def make_deferred_yieldable(deferred):
     returning a deferred. Then, when the deferred completes, restores the
     current logcontext before running callbacks/errbacks.
 
-    (This is more-or-less the opposite operation to preserve_fn.)
+    (This is more-or-less the opposite operation to run_in_background.)
     """
-    if isinstance(deferred, defer.Deferred) and not deferred.called:
-        prev_context = LoggingContext.set_current_context(LoggingContext.sentinel)
-        deferred.addBoth(_set_context_cb, prev_context)
+    if not isinstance(deferred, defer.Deferred):
+        return deferred
+
+    if deferred.called and not deferred.paused:
+        # it looks like this deferred is ready to run any callbacks we give it
+        # immediately. We may as well optimise out the logcontext faffery.
+        return deferred
+
+    # ok, we can't be sure that a yield won't block, so let's reset the
+    # logcontext, and add a callback to the deferred to restore it.
+    prev_context = LoggingContext.set_current_context(LoggingContext.sentinel)
+    deferred.addBoth(_set_context_cb, prev_context)
     return deferred
 
 

synapse/util/logformatter.py

@@ -14,7 +14,7 @@
 # limitations under the License.
 
 
-import StringIO
+from six import StringIO
 import logging
 import traceback
 
@@ -32,7 +32,7 @@ class LogFormatter(logging.Formatter):
         super(LogFormatter, self).__init__(*args, **kwargs)
 
     def formatException(self, ei):
-        sio = StringIO.StringIO()
+        sio = StringIO()
         (typ, val, tb) = ei
 
         # log the stack above the exception capture point if possible, but

synapse/util/ratelimitutils.py

@@ -18,7 +18,10 @@ from twisted.internet import defer
 from synapse.api.errors import LimitExceededError
 
 from synapse.util.async import sleep
-from synapse.util.logcontext import preserve_fn
+from synapse.util.logcontext import (
+    run_in_background, make_deferred_yieldable,
+    PreserveLoggingContext,
+)
 
 import collections
 import contextlib
@@ -150,7 +153,7 @@ class _PerHostRatelimiter(object):
                 "Ratelimit [%s]: sleeping req",
                 id(request_id),
             )
-            ret_defer = preserve_fn(sleep)(self.sleep_msec / 1000.0)
+            ret_defer = run_in_background(sleep, self.sleep_msec / 1000.0)
 
             self.sleeping_requests.add(request_id)
 
@@ -176,6 +179,9 @@ class _PerHostRatelimiter(object):
             return r
 
         def on_err(r):
+            # XXX: why is this necessary? this is called before we start
+            # processing the request so why would the request be in
+            # current_processing?
             self.current_processing.discard(request_id)
             return r
 
@@ -187,7 +193,7 @@ class _PerHostRatelimiter(object):
 
         ret_defer.addCallbacks(on_start, on_err)
         ret_defer.addBoth(on_both)
-        return ret_defer
+        return make_deferred_yieldable(ret_defer)
 
     def _on_exit(self, request_id):
         logger.debug(
@@ -197,7 +203,12 @@ class _PerHostRatelimiter(object):
         self.current_processing.discard(request_id)
         try:
             request_id, deferred = self.ready_request_queue.popitem()
+
+            # XXX: why do we do the following? the on_start callback above will
+            # do it for us.
             self.current_processing.add(request_id)
-            deferred.callback(None)
+
+            with PreserveLoggingContext():
+                deferred.callback(None)
         except KeyError:
             pass

synapse/util/retryutils.py

@@ -203,8 +203,8 @@ class RetryDestinationLimiter(object):
                 )
             except Exception:
                 logger.exception(
-                    "Failed to store set_destination_retry_timings",
+                    "Failed to store destination_retry_timings",
                 )
 
         # we deliberately do this in the background.
-        synapse.util.logcontext.preserve_fn(store_retry_timings)()
+        synapse.util.logcontext.run_in_background(store_retry_timings)

synapse/util/stringutils.py

@@ -15,6 +15,7 @@
 
 import random
 import string
+from six.moves import range
 
 _string_with_symbols = (
     string.digits + string.ascii_letters + ".,;:^&*-_+=#~@"
@@ -22,12 +23,12 @@ _string_with_symbols = (
 
 
 def random_string(length):
-    return ''.join(random.choice(string.ascii_letters) for _ in xrange(length))
+    return ''.join(random.choice(string.ascii_letters) for _ in range(length))
 
 
 def random_string_with_symbols(length):
     return ''.join(
-        random.choice(_string_with_symbols) for _ in xrange(length)
+        random.choice(_string_with_symbols) for _ in range(length)
     )
 
 

synapse/util/wheel_timer.py

@@ -13,6 +13,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+from six.moves import range
+
 
 class _Entry(object):
     __slots__ = ["end_key", "queue"]
@@ -68,7 +70,7 @@ class WheelTimer(object):
         # Add empty entries between the end of the current list and when we want
         # to insert. This ensures there are no gaps.
         self.entries.extend(
-            _Entry(key) for key in xrange(last_key, then_key + 1)
+            _Entry(key) for key in range(last_key, then_key + 1)
         )
 
         self.entries[-1].queue.append(obj)