fix: use servername callback instead of sni callback

tests/test_cert_manager.py

@@ -161,24 +161,26 @@ class TestRegistry(BaseTestCase):
             lambda: self.cert_manager.get_key("example.com"),
         )
 
-    def test_sni_callback_no_host(self) -> None:
+    def test_servername_callback_no_host(self) -> None:
         self._make_self_signed("example.com")
         with (
             self.patch("ssl.create_default_context", count=0),
         ):
-            self.cert_manager.sni_callback(self.socket_mock, None, self.context_mock)
+            self.cert_manager.servername_callback(
+                self.socket_mock, None, self.context_mock
+            )
 
-    def test_sni_callback_fail(self) -> None:
+    def test_servername_callback_fail(self) -> None:
         self._make_self_signed("example.com")
         with (
             self.patch("shutil.which", count=3),
             self.patch("ssl.create_default_context", count=0),
         ):
-            self.cert_manager.sni_callback(
+            self.cert_manager.servername_callback(
                 self.socket_mock, "example.fr", self.context_mock
             )
 
-    def test_sni_callback_create_context(self) -> None:
+    def test_servername_callback_create_context(self) -> None:
         self._make_self_signed("example.com")
         with (
             self.patch("ssl.create_default_context", return_value=self.context_mock),
@@ -191,18 +193,18 @@ class TestRegistry(BaseTestCase):
             ),
             self.patch("shutil.which", count=0),
         ):
-            self.cert_manager.sni_callback(
+            self.cert_manager.servername_callback(
                 self.socket_mock, "example.com", self.context_mock
             )
 
-    def test_sni_callback_create_context_fail(self) -> None:
+    def test_servername_callback_create_context_fail(self) -> None:
         self._make_self_signed("example.com")
         with (
             self.patch("ssl.create_default_context", return_value=self.context_mock),
             self.patch("shutil.which", count=0),
         ):
             self.context_mock.load_cert_chain.side_effect = Exception
-            self.cert_manager.sni_callback(
+            self.cert_manager.servername_callback(
                 self.socket_mock, "example.com", self.context_mock
             )
             self.context_mock.load_cert_chain.assert_called_once_with(

tests/test_server.py

@@ -65,7 +65,7 @@ class TestStaplerServer(BaseTestCase):
 
     def test_run_https(self) -> None:
         self.token_manager.detect_file_change.side_effect = KeyboardInterrupt
-        self.cert_manager.sni_callback = unittest.mock.Mock()
+        self.cert_manager.servername_callback = unittest.mock.Mock()
         with (
             self.mock_call(self.registry.load_pages),
             self.mock_call(self.cert_manager.init),
@@ -74,6 +74,7 @@ class TestStaplerServer(BaseTestCase):
             self.patch("ssl.create_default_context", return_value=self.context_mock),
             self.patch("http.server.ThreadingHTTPServer", self.server_mock, 2),
             self.mock_call_unchecked(self.context_mock.wrap_socket),
+            self.mock_call_unchecked(self.context_mock.set_servername_callback),
             self.mock_calls_unchecked(self.server_mock.serve_forever, 2),
             self.mock_call(self.server_mock.shutdown),
             self.seal_mocks(),