Record more information into structured logs. (#9654)

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

Author: clokep

changelog.d/9654.feature

@@ -0,0 +1 @@
+Include request information in structured logging output.

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 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 @@ def __init__(self, channel, *args, **kw):
 
         # 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 @@ def __repr__(self):
             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 @@ def get_method(self) -> str:
             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 @@ def _finished_processing(self):
         # 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)
@@ -305,14 +362,21 @@ def _finished_processing(self):
             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}"
             " Processed request: %.3fsec/%.3fsec (%.3fsec, %.3fsec) (%.3fsec/%.3fsec/%d)"
             ' %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,

synapse/logging/context.py

@@ -22,14 +22,14 @@
 
 See doc/log_contexts.rst for details on how this works.
 """
-
 import inspect
 import logging
 import threading
 import types
 import warnings
 from typing import TYPE_CHECKING, Optional, Tuple, TypeVar, Union
 
+import attr
 from typing_extensions import Literal
 
 from twisted.internet import defer, threads
@@ -181,6 +181,29 @@ def __sub__(self, other: "ContextResourceUsage") -> "ContextResourceUsage":
         return res
 
 
+@attr.s(slots=True)
+class ContextRequest:
+    """
+    A bundle of attributes from the SynapseRequest object.
+
+    This exists to:
+
+    * Avoid a cycle between LoggingContext and SynapseRequest.
+    * Be a single variable that can be passed from parent LoggingContexts to
+      their children.
+    """
+
+    request_id = attr.ib(type=str)
+    ip_address = attr.ib(type=str)
+    site_tag = attr.ib(type=str)
+    requester = attr.ib(type=Optional[str])
+    authenticated_entity = attr.ib(type=Optional[str])
+    method = attr.ib(type=str)
+    url = attr.ib(type=str)
+    protocol = attr.ib(type=str)
+    user_agent = attr.ib(type=str)
+
+
 LoggingContextOrSentinel = Union["LoggingContext", "_Sentinel"]
 
 
@@ -256,7 +279,7 @@ def __init__(
         self,
         name: Optional[str] = None,
         parent_context: "Optional[LoggingContext]" = None,
-        request: Optional[str] = None,
+        request: Optional[ContextRequest] = None,
     ) -> None:
         self.previous_context = current_context()
         self.name = name
@@ -281,15 +304,19 @@ def __init__(
         self.parent_context = parent_context
 
         if self.parent_context is not None:
-            self.parent_context.copy_to(self)
+            # we track the current request_id
+            self.request = self.parent_context.request
+
+            # we also track the current scope:
+            self.scope = self.parent_context.scope
 
         if request is not None:
             # the request param overrides the request from the parent context
             self.request = request
 
     def __str__(self) -> str:
         if self.request:
-            return str(self.request)
+            return self.request.request_id
         return "%s@%x" % (self.name, id(self))
 
     @classmethod
@@ -556,8 +583,23 @@ def filter(self, record: logging.LogRecord) -> Literal[True]:
         # we end up in a death spiral of infinite loops, so let's check, for
         # robustness' sake.
         if context is not None:
-            # Logging is interested in the request.
-            record.request = context.request  # type: ignore
+            # Logging is interested in the request ID. Note that for backwards
+            # compatibility this is stored as the "request" on the record.
+            record.request = str(context)  # type: ignore
+
+            # Add some data from the HTTP request.
+            request = context.request
+            if request is None:
+                return True
+
+            record.ip_address = request.ip_address  # type: ignore
+            record.site_tag = request.site_tag  # type: ignore
+            record.requester = request.requester  # type: ignore
+            record.authenticated_entity = request.authenticated_entity  # type: ignore
+            record.method = request.method  # type: ignore
+            record.url = request.url  # type: ignore
+            record.protocol = request.protocol  # type: ignore
+            record.user_agent = request.user_agent  # type: ignore
 
         return True
 
@@ -630,8 +672,8 @@ def set_current_context(context: LoggingContextOrSentinel) -> LoggingContextOrSe
 def nested_logging_context(suffix: str) -> LoggingContext:
     """Creates a new logging context as a child of another.
 
-    The nested logging context will have a 'request' made up of the parent context's
-    request, plus the given suffix.
+    The nested logging context will have a 'name' made up of the parent context's
+    name, plus the given suffix.
 
     CPU/db usage stats will be added to the parent context's on exit.
 
@@ -641,7 +683,7 @@ def nested_logging_context(suffix: str) -> LoggingContext:
             # ... do stuff
 
     Args:
-        suffix: suffix to add to the parent context's 'request'.
+        suffix: suffix to add to the parent context's 'name'.
 
     Returns:
         LoggingContext: new logging context.
@@ -653,11 +695,17 @@ def nested_logging_context(suffix: str) -> LoggingContext:
         )
         parent_context = None
         prefix = ""
+        request = None
     else:
         assert isinstance(curr_context, LoggingContext)
         parent_context = curr_context
-        prefix = str(parent_context.request)
-    return LoggingContext(parent_context=parent_context, request=prefix + "-" + suffix)
+        prefix = str(parent_context.name)
+        request = parent_context.request
+    return LoggingContext(
+        prefix + "-" + suffix,
+        parent_context=parent_context,
+        request=request,
+    )
 
 
 def preserve_fn(f):

synapse/metrics/background_process_metrics.py

@@ -16,7 +16,7 @@
 import logging
 import threading
 from functools import wraps
-from typing import TYPE_CHECKING, Dict, Optional, Set
+from typing import TYPE_CHECKING, Dict, Optional, Set, Union
 
 from prometheus_client.core import REGISTRY, Counter, Gauge
 
@@ -199,11 +199,11 @@ async def run():
         _background_process_start_count.labels(desc).inc()
         _background_process_in_flight_count.labels(desc).inc()
 
-        with BackgroundProcessLoggingContext(desc, "%s-%i" % (desc, count)) as context:
+        with BackgroundProcessLoggingContext(desc, count) as context:
             try:
                 ctx = noop_context_manager()
                 if bg_start_span:
-                    ctx = start_active_span(desc, tags={"request_id": context.request})
+                    ctx = start_active_span(desc, tags={"request_id": str(context)})
                 with ctx:
                     return await maybe_awaitable(func(*args, **kwargs))
             except Exception:
@@ -242,13 +242,19 @@ class BackgroundProcessLoggingContext(LoggingContext):
     processes.
     """
 
-    __slots__ = ["_proc"]
+    __slots__ = ["_id", "_proc"]
 
-    def __init__(self, name: str, request: Optional[str] = None):
-        super().__init__(name, request=request)
+    def __init__(self, name: str, id: Optional[Union[int, str]] = None):
+        super().__init__(name)
+        self._id = id
 
         self._proc = _BackgroundProcess(name, self)
 
+    def __str__(self) -> str:
+        if self._id is not None:
+            return "%s-%s" % (self.name, self._id)
+        return "%s@%x" % (self.name, id(self))
+
     def start(self, rusage: "Optional[resource._RUsage]"):
         """Log context has started running (again)."""
 

synapse/replication/tcp/protocol.py

@@ -184,8 +184,9 @@ def __init__(self, clock: Clock, handler: "ReplicationCommandHandler"):
 
         # a logcontext which we use for processing incoming commands. We declare it as a
         # background process so that the CPU stats get reported to prometheus.
-        ctx_name = "replication-conn-%s" % self.conn_id
-        self._logging_context = BackgroundProcessLoggingContext(ctx_name, ctx_name)
+        self._logging_context = BackgroundProcessLoggingContext(
+            "replication-conn", self.conn_id
+        )
 
     def connectionMade(self):
         logger.info("[%s] Connection established", self.id())