replies and debugging

db.py

@@ -1,3 +1,4 @@
+from BTrees.IIBTree import IIBTree
 from ZODB import DB
 from ZODB.Connection import Connection
 from ZODB.FileStorage import FileStorage
@@ -13,6 +14,15 @@ def get_conn(read_only=False) -> Connection:
     conn = db.open()
     if not hasattr(conn.root, 'subscribers'):
         conn.root.subscribers = PersistentMapping()
+    # migration 1
+    if not hasattr(conn.root, 'counter'):
+        conn.root.counter = 0
+    for user in conn.root.subscribers.values():  # type: Subscriber
+        if not hasattr(user, 'messages_forward') or not isinstance(user.messages_forward, IIBTree):
+            user.messages_forward = IIBTree()
+            user.messages_reverse = IIBTree()
+    # end migrations
+    commit()
     return conn
 
 
@@ -20,6 +30,8 @@ class Subscriber(Persistent):
     def __init__(self, user_id, name):
         self.uid = user_id
         self.name = name
+        self.messages_forward = IIBTree()
+        self.messages_reverse = IIBTree()
 
     def update_from_message(self, m: Message):
         self.name = Subscriber.get_name(m.chat)