4 files changed, 45 insertions, 21 deletions
diff --git a/synapse/logging/_remote.py b/synapse/logging/_remote.py
index 475756f1db..5a61b21eaf 100644
--- a/synapse/logging/_remote.py
+++ b/synapse/logging/_remote.py
@@ -31,7 +31,11 @@ from twisted.internet.endpoints import (
     TCP4ClientEndpoint,
     TCP6ClientEndpoint,
 )
-from twisted.internet.interfaces import IPushProducer, IStreamClientEndpoint
+from twisted.internet.interfaces import (
+    IPushProducer,
+    IReactorTCP,
+    IStreamClientEndpoint,
+)
 from twisted.internet.protocol import Factory, Protocol
 from twisted.internet.tcp import Connection
 from twisted.python.failure import Failure
@@ -59,14 +63,14 @@ class LogProducer:
     _buffer: Deque[logging.LogRecord]
     _paused: bool = attr.ib(default=False, init=False)
 
-    def pauseProducing(self):
+    def pauseProducing(self) -> None:
         self._paused = True
 
-    def stopProducing(self):
+    def stopProducing(self) -> None:
         self._paused = True
         self._buffer = deque()
 
-    def resumeProducing(self):
+    def resumeProducing(self) -> None:
         # If we're already producing, nothing to do.
         self._paused = False
 
@@ -102,8 +106,8 @@ class RemoteHandler(logging.Handler):
         host: str,
         port: int,
         maximum_buffer: int = 1000,
-        level=logging.NOTSET,
-        _reactor=None,
+        level: int = logging.NOTSET,
+        _reactor: Optional[IReactorTCP] = None,
     ):
         super().__init__(level=level)
         self.host = host
@@ -118,7 +122,7 @@ class RemoteHandler(logging.Handler):
         if _reactor is None:
             from twisted.internet import reactor
 
-            _reactor = reactor
+            _reactor = reactor  # type: ignore[assignment]
 
         try:
             ip = ip_address(self.host)
@@ -139,7 +143,7 @@ class RemoteHandler(logging.Handler):
         self._stopping = False
         self._connect()
 
-    def close(self):
+    def close(self) -> None:
         self._stopping = True
         self._service.stopService()
 
diff --git a/synapse/logging/formatter.py b/synapse/logging/formatter.py
index c0f12ecd15..c88b8ae545 100644
--- a/synapse/logging/formatter.py
+++ b/synapse/logging/formatter.py
@@ -16,6 +16,8 @@
 import logging
 import traceback
 from io import StringIO
+from types import TracebackType
+from typing import Optional, Tuple, Type
 
 
 class LogFormatter(logging.Formatter):
@@ -28,10 +30,14 @@ class LogFormatter(logging.Formatter):
     where it was caught are logged).
     """
 
-    def __init__(self, *args, **kwargs):
-        super().__init__(*args, **kwargs)
-
-    def formatException(self, ei):
+    def formatException(
+        self,
+        ei: Tuple[
+            Optional[Type[BaseException]],
+            Optional[BaseException],
+            Optional[TracebackType],
+        ],
+    ) -> str:
         sio = StringIO()
         (typ, val, tb) = ei
 
diff --git a/synapse/logging/handlers.py b/synapse/logging/handlers.py
index 478b527494..dec2a2c3dd 100644
--- a/synapse/logging/handlers.py
+++ b/synapse/logging/handlers.py
@@ -49,7 +49,7 @@ class PeriodicallyFlushingMemoryHandler(MemoryHandler):
         )
         self._flushing_thread.start()
 
-        def on_reactor_running():
+        def on_reactor_running() -> None:
             self._reactor_started = True
 
         reactor_to_use: IReactorCore
@@ -74,7 +74,7 @@ class PeriodicallyFlushingMemoryHandler(MemoryHandler):
         else:
             return True
 
-    def _flush_periodically(self):
+    def _flush_periodically(self) -> None:
         """
         Whilst this handler is active, flush the handler periodically.
         """
diff --git a/synapse/logging/scopecontextmanager.py b/synapse/logging/scopecontextmanager.py
index d57e7c5324..a26a1a58e7 100644
--- a/synapse/logging/scopecontextmanager.py
+++ b/synapse/logging/scopecontextmanager.py
@@ -13,6 +13,8 @@
 # limitations under the License.import logging
 
 import logging
+from types import TracebackType
+from typing import Optional, Type
 
 from opentracing import Scope, ScopeManager
 
@@ -107,19 +109,26 @@ class _LogContextScope(Scope):
         and - if enter_logcontext was set - the logcontext is finished too.
     """
 
-    def __init__(self, manager, span, logcontext, enter_logcontext, finish_on_close):
+    def __init__(
+        self,
+        manager: LogContextScopeManager,
+        span,
+        logcontext,
+        enter_logcontext: bool,
+        finish_on_close: bool,
+    ):
         """
         Args:
-            manager (LogContextScopeManager):
+            manager:
                 the manager that is responsible for this scope.
             span (Span):
                 the opentracing span which this scope represents the local
                 lifetime for.
             logcontext (LogContext):
                 the logcontext to which this scope is attached.
-            enter_logcontext (Boolean):
+            enter_logcontext:
                 if True the logcontext will be exited when the scope is finished
-            finish_on_close (Boolean):
+            finish_on_close:
                 if True finish the span when the scope is closed
         """
         super().__init__(manager, span)
@@ -127,16 +136,21 @@ class _LogContextScope(Scope):
         self._finish_on_close = finish_on_close
         self._enter_logcontext = enter_logcontext
 
-    def __exit__(self, exc_type, value, traceback):
+    def __exit__(
+        self,
+        exc_type: Optional[Type[BaseException]],
+        value: Optional[BaseException],
+        traceback: Optional[TracebackType],
+    ) -> None:
         if exc_type == twisted.internet.defer._DefGen_Return:
             # filter out defer.returnValue() calls
             exc_type = value = traceback = None
         super().__exit__(exc_type, value, traceback)
 
-    def __str__(self):
+    def __str__(self) -> str:
         return f"Scope<{self.span}>"
 
-    def close(self):
+    def close(self) -> None:
         active_scope = self.manager.active
         if active_scope is not self:
             logger.error(