An initial hack at storing presence state-change mtimes in database and presenting age durations to clients/federation events

synapse/storage/_base.py

@@ -29,6 +29,7 @@ class SQLBaseStore(object):
     def __init__(self, hs):
         self.hs = hs
         self._db_pool = hs.get_db_pool()
+        self._clock = hs.get_clock()
 
     def cursor_to_dict(self, cursor):
         """Converts a SQL cursor into an list of dicts.

synapse/storage/presence.py

@@ -35,7 +35,7 @@ class PresenceStore(SQLBaseStore):
         return self._simple_select_one(
             table="presence",
             keyvalues={"user_id": user_localpart},
-            retcols=["state", "status_msg"],
+            retcols=["state", "status_msg", "mtime"],
         )
 
     def set_presence_state(self, user_localpart, new_state):
@@ -43,7 +43,8 @@ class PresenceStore(SQLBaseStore):
             table="presence",
             keyvalues={"user_id": user_localpart},
             updatevalues={"state": new_state["state"],
-                          "status_msg": new_state["status_msg"]},
+                          "status_msg": new_state["status_msg"],
+                          "mtime": self._clock.time_msec()},
             retcols=["state"],
         )
 

synapse/storage/schema/presence.sql

@@ -16,6 +16,7 @@ CREATE TABLE IF NOT EXISTS presence(
   user_id INTEGER NOT NULL,
   state INTEGER,
   status_msg TEXT,
+  mtime INTEGER, -- miliseconds since last state change
   FOREIGN KEY(user_id) REFERENCES users(id)
 );