From caee7dae44c4b73c13b4d5044d7e320eb0bd9041 Mon Sep 17 00:00:00 2001
From: Andrew Morgan <andrew@amorgan.xyz>
Date: Wed, 5 May 2021 12:04:21 +0100
Subject: [PATCH] Remove users_to_send_full_presence_to table culling; add fk
 for user_id

---
 synapse/storage/databases/main/presence.py    | 37 ++++---------------
 .../59/12users_to_send_full_presence_to.sql   | 10 ++---
 2 files changed, 12 insertions(+), 35 deletions(-)

diff --git a/synapse/storage/databases/main/presence.py b/synapse/storage/databases/main/presence.py
index ed20494d4e..bd7d60be9c 100644
--- a/synapse/storage/databases/main/presence.py
+++ b/synapse/storage/databases/main/presence.py
@@ -23,15 +23,11 @@ from synapse.storage.types import Connection
 from synapse.storage.util.id_generators import MultiWriterIdGenerator, StreamIdGenerator
 from synapse.util.caches.descriptors import cached, cachedList
 from synapse.util.caches.stream_change_cache import StreamChangeCache
-from synapse.util.constants import HOUR_IN_MS
 from synapse.util.iterutils import batch_iter
 
 if TYPE_CHECKING:
     from synapse.server import HomeServer
 
-# How long to keep entries in the users_to_send_full_presence_to db table
-USERS_TO_SEND_FULL_PRESENCE_TO_ENTRY_LIFETIME_MS = 14 * 24 * HOUR_IN_MS
-
 
 class PresenceStore(SQLBaseStore):
     def __init__(
@@ -247,31 +243,14 @@ class PresenceStore(SQLBaseStore):
         Args:
             user_ids: An iterable of user IDs.
         """
-        time_now = self.hs.get_clock().time_msec()
-
-        def _add_users_to_send_full_presence_to_txn(txn):
-            # Add user entries to the table (or update their added_ms if they already exist)
-            self.db_pool.simple_upsert_many_txn(
-                txn,
-                table="users_to_send_full_presence_to",
-                key_names=("user_id",),
-                key_values=((user_id,) for user_id in user_ids),
-                value_names=("added_ms",),
-                value_values=((time_now,) for _ in user_ids),
-            )
-
-            # Delete entries in the table that have expired
-            sql = """
-                DELETE FROM users_to_send_full_presence_to
-                WHERE added_ms < ?
-            """
-            txn.execute(
-                sql, (time_now - USERS_TO_SEND_FULL_PRESENCE_TO_ENTRY_LIFETIME_MS,)
-            )
-
-        await self.db_pool.runInteraction(
-            "add_users_to_send_full_presence_to",
-            _add_users_to_send_full_presence_to_txn,
+        # Add user entries to the table
+        await self.db_pool.simple_upsert_many(
+            table="users_to_send_full_presence_to",
+            key_names=("user_id",),
+            key_values=[(user_id,) for user_id in user_ids],
+            value_names=(),
+            value_values=(),
+            desc="add_users_to_send_full_presence_to",
         )
 
     async def remove_user_from_users_to_send_full_presence_to(self, user_id: str):
diff --git a/synapse/storage/databases/main/schema/delta/59/12users_to_send_full_presence_to.sql b/synapse/storage/databases/main/schema/delta/59/12users_to_send_full_presence_to.sql
index 34ec1c0268..c01c4e177a 100644
--- a/synapse/storage/databases/main/schema/delta/59/12users_to_send_full_presence_to.sql
+++ b/synapse/storage/databases/main/schema/delta/59/12users_to_send_full_presence_to.sql
@@ -22,10 +22,8 @@
 -- want to duplicate work across multiple sync workers.
 
 CREATE TABLE IF NOT EXISTS users_to_send_full_presence_to(
+    -- The user ID to send full presence to.
     user_id TEXT PRIMARY KEY,
-    added_ms BIGINT NOT NULL
-);
-
--- For checking expired entries
-CREATE INDEX IF NOT EXISTS users_to_send_full_presence_to_added_ms
-    ON users_to_send_full_presence_to(added_ms);
\ No newline at end of file
+    FOREIGN KEY (user_id)
+        REFERENCES users (name)
+);
\ No newline at end of file