Record more information into structured logs. (#9654)

Records additional request information into the structured logs,
e.g. the requester, IP address, etc.

synapse/http/site.py

@@ -14,7 +14,7 @@
 import contextlib
 import logging
 import time
-from typing import Optional, Type, Union
+from typing import Optional, Tuple, Type, Union
 
 import attr
 from zope.interface import implementer
@@ -26,7 +26,11 @@ from twisted.web.server import Request, Site
 from synapse.config.server import ListenerConfig
 from synapse.http import get_request_user_agent, redact_uri
 from synapse.http.request_metrics import RequestMetrics, requests_counter
-from synapse.logging.context import LoggingContext, PreserveLoggingContext
+from synapse.logging.context import (
+    ContextRequest,
+    LoggingContext,
+    PreserveLoggingContext,
+)
 from synapse.types import Requester
 
 logger = logging.getLogger(__name__)
@@ -63,7 +67,7 @@ class SynapseRequest(Request):
 
         # The requester, if authenticated. For federation requests this is the
         # server name, for client requests this is the Requester object.
-        self.requester = None  # type: Optional[Union[Requester, str]]
+        self._requester = None  # type: Optional[Union[Requester, str]]
 
         # we can't yet create the logcontext, as we don't know the method.
         self.logcontext = None  # type: Optional[LoggingContext]
@@ -93,6 +97,31 @@ class SynapseRequest(Request):
             self.site.site_tag,
         )
 
+    @property
+    def requester(self) -> Optional[Union[Requester, str]]:
+        return self._requester
+
+    @requester.setter
+    def requester(self, value: Union[Requester, str]) -> None:
+        # Store the requester, and update some properties based on it.
+
+        # This should only be called once.
+        assert self._requester is None
+
+        self._requester = value
+
+        # A logging context should exist by now (and have a ContextRequest).
+        assert self.logcontext is not None
+        assert self.logcontext.request is not None
+
+        (
+            requester,
+            authenticated_entity,
+        ) = self.get_authenticated_entity()
+        self.logcontext.request.requester = requester
+        # If there's no authenticated entity, it was the requester.
+        self.logcontext.request.authenticated_entity = authenticated_entity or requester
+
     def get_request_id(self):
         return "%s-%i" % (self.get_method(), self.request_seq)
 
@@ -126,13 +155,60 @@ class SynapseRequest(Request):
             return self.method.decode("ascii")
         return method
 
+    def get_authenticated_entity(self) -> Tuple[Optional[str], Optional[str]]:
+        """
+        Get the "authenticated" entity of the request, which might be the user
+        performing the action, or a user being puppeted by a server admin.
+
+        Returns:
+            A tuple:
+                The first item is a string representing the user making the request.
+
+                The second item is a string or None representing the user who
+                authenticated when making this request. See
+                Requester.authenticated_entity.
+        """
+        # Convert the requester into a string that we can log
+        if isinstance(self._requester, str):
+            return self._requester, None
+        elif isinstance(self._requester, Requester):
+            requester = self._requester.user.to_string()
+            authenticated_entity = self._requester.authenticated_entity
+
+            # If this is a request where the target user doesn't match the user who
+            # authenticated (e.g. and admin is puppetting a user) then we return both.
+            if self._requester.user.to_string() != authenticated_entity:
+                return requester, authenticated_entity
+
+            return requester, None
+        elif self._requester is not None:
+            # This shouldn't happen, but we log it so we don't lose information
+            # and can see that we're doing something wrong.
+            return repr(self._requester), None  # type: ignore[unreachable]
+
+        return None, None
+
     def render(self, resrc):
         # this is called once a Resource has been found to serve the request; in our
         # case the Resource in question will normally be a JsonResource.
 
         # create a LogContext for this request
         request_id = self.get_request_id()
-        self.logcontext = LoggingContext(request_id, request=request_id)
+        self.logcontext = LoggingContext(
+            request_id,
+            request=ContextRequest(
+                request_id=request_id,
+                ip_address=self.getClientIP(),
+                site_tag=self.site.site_tag,
+                # The requester is going to be unknown at this point.
+                requester=None,
+                authenticated_entity=None,
+                method=self.get_method(),
+                url=self.get_redacted_uri(),
+                protocol=self.clientproto.decode("ascii", errors="replace"),
+                user_agent=get_request_user_agent(self),
+            ),
+        )
 
         # override the Server header which is set by twisted
         self.setHeader("Server", self.site.server_version_string)
@@ -277,25 +353,6 @@ class SynapseRequest(Request):
         # to the client (nb may be negative)
         response_send_time = self.finish_time - self._processing_finished_time
 
-        # Convert the requester into a string that we can log
-        authenticated_entity = None
-        if isinstance(self.requester, str):
-            authenticated_entity = self.requester
-        elif isinstance(self.requester, Requester):
-            authenticated_entity = self.requester.authenticated_entity
-
-            # If this is a request where the target user doesn't match the user who
-            # authenticated (e.g. and admin is puppetting a user) then we log both.
-            if self.requester.user.to_string() != authenticated_entity:
-                authenticated_entity = "{},{}".format(
-                    authenticated_entity,
-                    self.requester.user.to_string(),
-                )
-        elif self.requester is not None:
-            # This shouldn't happen, but we log it so we don't lose information
-            # and can see that we're doing something wrong.
-            authenticated_entity = repr(self.requester)  # type: ignore[unreachable]
-
         user_agent = get_request_user_agent(self, "-")
 
         code = str(self.code)
@@ -305,6 +362,13 @@ class SynapseRequest(Request):
             code += "!"
 
         log_level = logging.INFO if self._should_log_request() else logging.DEBUG
+
+        # If this is a request where the target user doesn't match the user who
+        # authenticated (e.g. and admin is puppetting a user) then we log both.
+        requester, authenticated_entity = self.get_authenticated_entity()
+        if authenticated_entity:
+            requester = "{}.{}".format(authenticated_entity, requester)
+
         self.site.access_logger.log(
             log_level,
             "%s - %s - {%s}"
@@ -312,7 +376,7 @@ class SynapseRequest(Request):
             ' %sB %s "%s %s %s" "%s" [%d dbevts]',
             self.getClientIP(),
             self.site.site_tag,
-            authenticated_entity,
+            requester,
             processing_time,
             response_send_time,
             usage.ru_utime,