From c4ee004d2c40bf7c185f4dc3879c4aa78a4cc26c Mon Sep 17 00:00:00 2001
From: Richard van der Hoff <richard@matrix.org>
Date: Wed, 21 Apr 2021 16:21:54 +0100
Subject: [PATCH] Make LoggingContext's name optional

Fixes https://github.com/matrix-org/synapse-s3-storage-provider/issues/55
---
 changelog.d/9857.bugfix    |  1 +
 synapse/logging/context.py | 15 ++++++++++++---
 2 files changed, 13 insertions(+), 3 deletions(-)
 create mode 100644 changelog.d/9857.bugfix

diff --git a/changelog.d/9857.bugfix b/changelog.d/9857.bugfix
new file mode 100644
index 000000000000..7eed41594df7
--- /dev/null
+++ b/changelog.d/9857.bugfix
@@ -0,0 +1 @@
+Fix a regression in Synapse v1.32.1 which caused `LoggingContext` errors in plugins.
diff --git a/synapse/logging/context.py b/synapse/logging/context.py
index dbd7d3a33a6e..01a3789c2687 100644
--- a/synapse/logging/context.py
+++ b/synapse/logging/context.py
@@ -258,7 +258,8 @@ class LoggingContext:
           child to the parent
 
     Args:
-        name (str): Name for the context for debugging.
+        name: Name for the context for logging. If this is omitted, it is
+           inherited from the parent context.
         parent_context (LoggingContext|None): The parent of the new context
     """
 
@@ -277,12 +278,11 @@ class LoggingContext:
 
     def __init__(
         self,
-        name: str,
+        name: Optional[str] = None,
         parent_context: "Optional[LoggingContext]" = None,
         request: Optional[ContextRequest] = None,
     ) -> None:
         self.previous_context = current_context()
-        self.name = name
 
         # track the resources used by this context so far
         self._resource_usage = ContextResourceUsage()
@@ -314,6 +314,15 @@ def __init__(
             # the request param overrides the request from the parent context
             self.request = request
 
+        # if we don't have a `name`, but do have a parent context, use its name.
+        if self.parent_context and not name:
+            name = str(self.parent_context)
+        if not name:
+            raise ValueError(
+                "LoggingContext must be given either a name or a parent context"
+            )
+        self.name = name
+
     def __str__(self) -> str:
         return self.name