1 files changed, 7 insertions, 0 deletions
diff --git a/synapse/api/constants.py b/synapse/api/constants.py
index 6432d32d83..6f9239d21c 100644
--- a/synapse/api/constants.py
+++ b/synapse/api/constants.py
@@ -17,6 +17,8 @@
 
 """Contains constants from the specification."""
 
+import enum
+
 from typing_extensions import Final
 
 # the max size of a (canonical-json-encoded) event
@@ -290,3 +292,8 @@ class ApprovalNoticeMedium:
 
     NONE = "org.matrix.msc3866.none"
     EMAIL = "org.matrix.msc3866.email"
+
+
+class Direction(enum.Enum):
+    BACKWARDS = "b"
+    FORWARDS = "f"