Add `StreamKeyType` class and replace string literals with constants (#12567)

1 files changed, 14 insertions, 9 deletions

diff --git a/synapse/handlers/sync.py b/synapse/handlers/sync.py
index 2c555a66d0..4be08fe7cb 100644
--- a/synapse/handlers/sync.py
+++ b/synapse/handlers/sync.py
@@ -37,6 +37,7 @@ from synapse.types import (
     Requester,
     RoomStreamToken,
     StateMap,
+    StreamKeyType,
     StreamToken,
     UserID,
 )
@@ -449,7 +450,7 @@ class SyncHandler:
                 room_ids=room_ids,
                 is_guest=sync_config.is_guest,
             )
-            now_token = now_token.copy_and_replace("typing_key", typing_key)
+            now_token = now_token.copy_and_replace(StreamKeyType.TYPING, typing_key)
 
             ephemeral_by_room: JsonDict = {}
 
@@ -471,7 +472,7 @@ class SyncHandler:
                 room_ids=room_ids,
                 is_guest=sync_config.is_guest,
             )
-            now_token = now_token.copy_and_replace("receipt_key", receipt_key)
+            now_token = now_token.copy_and_replace(StreamKeyType.RECEIPT, receipt_key)
 
             for event in receipts:
                 room_id = event["room_id"]
@@ -537,7 +538,9 @@ class SyncHandler:
                 prev_batch_token = now_token
                 if recents:
                     room_key = recents[0].internal_metadata.before
-                    prev_batch_token = now_token.copy_and_replace("room_key", room_key)
+                    prev_batch_token = now_token.copy_and_replace(
+                        StreamKeyType.ROOM, room_key
+                    )
 
                 return TimelineBatch(
                     events=recents, prev_batch=prev_batch_token, limited=False
@@ -611,7 +614,7 @@ class SyncHandler:
                 recents = recents[-timeline_limit:]
                 room_key = recents[0].internal_metadata.before
 
-            prev_batch_token = now_token.copy_and_replace("room_key", room_key)
+            prev_batch_token = now_token.copy_and_replace(StreamKeyType.ROOM, room_key)
 
         # Don't bother to bundle aggregations if the timeline is unlimited,
         # as clients will have all the necessary information.
@@ -1398,7 +1401,7 @@ class SyncHandler:
                 now_token.to_device_key,
             )
             sync_result_builder.now_token = now_token.copy_and_replace(
-                "to_device_key", stream_id
+                StreamKeyType.TO_DEVICE, stream_id
             )
             sync_result_builder.to_device = messages
         else:
@@ -1503,7 +1506,7 @@ class SyncHandler:
         )
         assert presence_key
         sync_result_builder.now_token = now_token.copy_and_replace(
-            "presence_key", presence_key
+            StreamKeyType.PRESENCE, presence_key
         )
 
         extra_users_ids = set(newly_joined_or_invited_users)
@@ -1826,7 +1829,7 @@ class SyncHandler:
                 # stream token as it'll only be used in the context of this
                 # room. (c.f. the docstring of `to_room_stream_token`).
                 leave_token = since_token.copy_and_replace(
-                    "room_key", leave_position.to_room_stream_token()
+                    StreamKeyType.ROOM, leave_position.to_room_stream_token()
                 )
 
                 # If this is an out of band message, like a remote invite
@@ -1875,7 +1878,9 @@ class SyncHandler:
             if room_entry:
                 events, start_key = room_entry
 
-                prev_batch_token = now_token.copy_and_replace("room_key", start_key)
+                prev_batch_token = now_token.copy_and_replace(
+                    StreamKeyType.ROOM, start_key
+                )
 
                 entry = RoomSyncResultBuilder(
                     room_id=room_id,
@@ -1972,7 +1977,7 @@ class SyncHandler:
                             continue
 
                 leave_token = now_token.copy_and_replace(
-                    "room_key", RoomStreamToken(None, event.stream_ordering)
+                    StreamKeyType.ROOM, RoomStreamToken(None, event.stream_ordering)
                 )
                 room_entries.append(
                     RoomSyncResultBuilder(