Make curve keys private and typed

Author: krassowski

ipykernel/heartbeat.py

@@ -48,8 +48,8 @@ def __init__(self, context, addr=None, *, curve_publickey=None, curve_secretkey=
         self.context = context
         self.transport, self.ip, self.port = addr
         self.original_port = self.port
-        self.curve_publickey = curve_publickey
-        self.curve_secretkey = curve_secretkey
+        self._curve_publickey = curve_publickey
+        self._curve_secretkey = curve_secretkey
         if self.original_port == 0:
             self.pick_port()
         self.addr = (self.ip, self.port)
@@ -109,9 +109,9 @@ def run(self):
         self.name = "Heartbeat"
         self.socket = self.context.socket(zmq.ROUTER)
         self.socket.linger = 1000
-        if self.curve_secretkey is not None:
-            self.socket.curve_secretkey = self.curve_secretkey
-            self.socket.curve_publickey = self.curve_publickey
+        if self._curve_secretkey is not None:
+            self.socket.curve_secretkey = self._curve_secretkey
+            self.socket.curve_publickey = self._curve_publickey
             self.socket.curve_server = True
         try:
             self._bind_socket()
@@ -141,3 +141,6 @@ def run(self):
                 raise
             else:
                 break
+
+    _curve_publickey: bytes | None
+    _curve_secretkey: bytes | None