Merge branch 'develop' of github.com:matrix-org/synapse into anoa/user_param_ui_auth github/anoa/user_param_ui_auth anoa/user_param_ui_auth

* 'develop' of github.com:matrix-org/synapse: (369 commits)
  Add functions to `MultiWriterIdGen` used by events stream (#8164)
  Do not allow send_nonmember_event to be called with shadow-banned users. (#8158)
  Changelog fixes
  1.19.1rc1
  Make StreamIdGen `get_next` and `get_next_mult` async  (#8161)
  Wording fixes to 'name' user admin api filter (#8163)
  Fix missing double-backtick in RST document
  Search in columns 'name' and 'displayname' in the admin users endpoint (#7377)
  Add type hints for state. (#8140)
  Stop shadow-banned users from sending non-member events. (#8142)
  Allow capping a room's retention policy (#8104)
  Add healthcheck for default localhost 8008 port on /health endpoint. (#8147)
  Fix flaky shadow-ban tests. (#8152)
  Fix join ratelimiter breaking profile updates and idempotency (#8153)
  Do not apply ratelimiting on joins to appservices (#8139)
  Don't fail /submit_token requests on incorrect session ID if request_token_inhibit_3pid_errors is turned on (#7991)
  Do not apply ratelimiting on joins to appservices (#8139)
  Micro-optimisations to get_auth_chain_ids (#8132)
  Allow denying or shadow banning registrations via the spam checker (#8034)
  Stop shadow-banned users from sending invites. (#8095)
  ...

1 files changed, 14 insertions, 16 deletions

diff --git a/synapse/metrics/background_process_metrics.py b/synapse/metrics/background_process_metrics.py

index 13785038ad..4cd7932e5b 100644
--- a/synapse/metrics/background_process_metrics.py
+++ b/synapse/metrics/background_process_metrics.py
@@ -13,9 +13,9 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import inspect
 import logging
 import threading
-from asyncio import iscoroutine
 from functools import wraps
 from typing import TYPE_CHECKING, Dict, Optional, Set
 
@@ -166,7 +166,7 @@ class _BackgroundProcess(object):
         )
 
 
-def run_as_background_process(desc, func, *args, **kwargs):
+def run_as_background_process(desc: str, func, *args, **kwargs):
     """Run the given function in its own logcontext, with resource metrics
 
     This should be used to wrap processes which are fired off to run in the
@@ -175,10 +175,10 @@ def run_as_background_process(desc, func, *args, **kwargs):
     It returns a Deferred which completes when the function completes, but it doesn't
     follow the synapse logcontext rules, which makes it appropriate for passing to
     clock.looping_call and friends (or for firing-and-forgetting in the middle of a
-    normal synapse inlineCallbacks function).
+    normal synapse async function).
 
     Args:
-        desc (str): a description for this background process type
+        desc: a description for this background process type
         func: a function, which may return a Deferred or a coroutine
         args: positional args for func
         kwargs: keyword args for func
@@ -187,8 +187,7 @@ def run_as_background_process(desc, func, *args, **kwargs):
         follow the synapse logcontext rules.
     """
 
-    @defer.inlineCallbacks
-    def run():
+    async def run():
         with _bg_metrics_lock:
             count = _background_process_counts.get(desc, 0)
             _background_process_counts[desc] = count + 1
@@ -202,22 +201,21 @@ def run_as_background_process(desc, func, *args, **kwargs):
             try:
                 result = func(*args, **kwargs)
 
-                # We probably don't have an ensureDeferred in our call stack to handle
-                # coroutine results, so we need to ensureDeferred here.
-                #
-                # But we need this check because ensureDeferred doesn't like being
-                # called on immediate values (as opposed to Deferreds or coroutines).
-                if iscoroutine(result):
-                    result = defer.ensureDeferred(result)
+                if inspect.isawaitable(result):
+                    result = await result
 
-                return (yield result)
+                return result
             except Exception:
-                logger.exception("Background process '%s' threw an exception", desc)
+                logger.exception(
+                    "Background process '%s' threw an exception", desc,
+                )
             finally:
                 _background_process_in_flight_count.labels(desc).dec()
 
     with PreserveLoggingContext():
-        return run()
+        # Note that we return a Deferred here so that it can be used in a
+        # looping_call and other places that expect a Deferred.
+        return defer.ensureDeferred(run())
 
 
 def wrap_as_background_process(desc):