1 files changed, 7 insertions, 0 deletions
diff --git a/synapse/types.py b/synapse/types.py
index 111948540d..37d5fa7f9f 100644
--- a/synapse/types.py
+++ b/synapse/types.py
@@ -156,6 +156,11 @@ class EventID(DomainSpecificString):
     SIGIL = "$"
 
 
+class GroupID(DomainSpecificString):
+    """Structure representing a group ID."""
+    SIGIL = "+"
+
+
 class StreamToken(
     namedtuple("Token", (
         "room_key",
@@ -166,6 +171,7 @@ class StreamToken(
         "push_rules_key",
         "to_device_key",
         "device_list_key",
+        "groups_key",
     ))
 ):
     _SEPARATOR = "_"
@@ -204,6 +210,7 @@ class StreamToken(
             or (int(other.push_rules_key) < int(self.push_rules_key))
             or (int(other.to_device_key) < int(self.to_device_key))
             or (int(other.device_list_key) < int(self.device_list_key))
+            or (int(other.groups_key) < int(self.groups_key))
         )
 
     def copy_and_advance(self, key, new_value):