xmlstream: make dns_answers private

slixmpp/xmlstream/xmlstream.py

@@ -16,10 +16,12 @@ from typing import (
     Any,
     Callable,
     Iterable,
+    Iterator,
     List,
     Optional,
     Set,
     Union,
+    Tuple,
 )
 
 import functools
@@ -212,7 +214,7 @@ class XMLStream(asyncio.BaseProtocol):
         self._current_connection_attempt = None
 
         #: A list of DNS results that have not yet been tried.
-        self.dns_answers = None
+        self._dns_answers: Optional[Iterator[Tuple[str, str, int]]] = None
 
         #: The service name to check with DNS SRV records. For
         #: example, setting this to ``'xmpp-client'`` would query the
@@ -315,7 +317,7 @@ class XMLStream(asyncio.BaseProtocol):
             self.event('reconnect_delay', self._connect_loop_wait)
             await asyncio.sleep(self._connect_loop_wait, loop=self.loop)
 
-        record = await self.pick_dns_answer(self.default_domain)
+        record = await self._pick_dns_answer(self.default_domain)
         if record is not None:
             host, address, dns_port = record
             port = dns_port if dns_port else self.address[1]
@@ -324,7 +326,7 @@ class XMLStream(asyncio.BaseProtocol):
         else:
             # No DNS records left, stop iterating
             # and try (host, port) as a last resort
-            self.dns_answers = None
+            self._dns_answers = None
 
         if self.use_ssl:
             ssl_context = self.get_ssl_context()
@@ -392,7 +394,7 @@ class XMLStream(asyncio.BaseProtocol):
         self._current_connection_attempt = None
         self.init_parser()
         self.send_raw(self.stream_header)
-        self.dns_answers = None
+        self._dns_answers = None
 
     def data_received(self, data):
         """Called when incoming data is received on the socket.
@@ -777,7 +779,7 @@ class XMLStream(asyncio.BaseProtocol):
             idx += 1
         return False
 
-    async def get_dns_records(self, domain, port=None):
+    async def get_dns_records(self, domain: str, port: Optional[int] = None) -> List[Tuple[str, str, int]]:
         """Get the DNS records for a domain.
 
         :param domain: The domain in question.
@@ -797,7 +799,7 @@ class XMLStream(asyncio.BaseProtocol):
                                     loop=self.loop)
         return result
 
-    async def pick_dns_answer(self, domain, port=None):
+    async def _pick_dns_answer(self, domain: str, port: Optional[int] = None) -> Optional[Tuple[str, str, int]]:
         """Pick a server and port from DNS answers.
 
         Gets DNS answers if none available.
@@ -806,12 +808,12 @@ class XMLStream(asyncio.BaseProtocol):
         :param domain: The domain in question.
         :param port: If the results don't include a port, use this one.
         """
-        if self.dns_answers is None:
+        if self._dns_answers is None:
             dns_records = await self.get_dns_records(domain, port)
-            self.dns_answers = iter(dns_records)
+            self._dns_answers = iter(dns_records)
 
         try:
-            return next(self.dns_answers)
+            return next(self._dns_answers)
         except StopIteration:
             return