refactor: prepare src/database/key_value.rs from src/service/rooms/state/data.rs

src/database/key_value.rs

@@ -0,0 +1,16 @@
+pub trait Data {
+    fn get_room_shortstatehash(room_id: &RoomId);
+}
+
+    /// Returns the last state hash key added to the db for the given room.
+    #[tracing::instrument(skip(self))]
+    pub fn current_shortstatehash(&self, room_id: &RoomId) -> Result<Option<u64>> {
+        self.roomid_shortstatehash
+            .get(room_id.as_bytes())?
+            .map_or(Ok(None), |bytes| {
+                Ok(Some(utils::u64_from_bytes(&bytes).map_err(|_| {
+                    Error::bad_database("Invalid shortstatehash in roomid_shortstatehash")
+                })?))
+            })
+    }
+