network: Catch and react on TimeoutError

This is low level timeout error, which can happend outside of socket.timeout,
see https://docs.python.org/3/library/exceptions.html#TimeoutError

/reviewed-on nexedi/surykatka!8

src/surykatka/network.py

@@ -88,7 +88,7 @@ def isTcpPortOpen(db, ip, port, status_id, timeout=TIMEOUT):
         is_open = True
     except ConnectionRefusedError:
         state = "closed"
-    except socket.timeout:
+    except (socket.timeout, TimeoutError):
         state = "filtered"
     except OSError as e:
         if e.errno == errno.EHOSTUNREACH:

tests/test_network.py

@@ -271,6 +271,37 @@ class SurykatkaNetworkTestCase(unittest.TestCase):
         assert self.db.NetworkChange.get().status_id == status_id
         assert result == False
 
+    def test_isTcpPortOpen_timeouterror(self):
+        ip = "127.0.0.1"
+        port = 1234
+        status_id = logStatus(self.db, "foo")
+
+        with mock.patch("surykatka.network.socket.socket") as mock_socket:
+
+            def sideEffect(*args, **kw):
+                raise TimeoutError
+
+            mock_socket.return_value.connect.side_effect = sideEffect
+
+            result = isTcpPortOpen(self.db, ip, port, status_id)
+            assert mock_socket.call_count == 1
+
+            assert mock_socket.return_value.settimeout.call_count == 1
+            mock_socket.return_value.settimeout.assert_called_with(2)
+
+            assert mock_socket.return_value.connect.call_count == 1
+            mock_socket.return_value.connect.assert_called_with((ip, port))
+
+            assert mock_socket.return_value.close.call_count == 1
+
+        assert self.db.NetworkChange.select().count() == 1
+        assert self.db.NetworkChange.get().ip == ip
+        assert self.db.NetworkChange.get().port == port
+        assert self.db.NetworkChange.get().transport == "TCP"
+        assert self.db.NetworkChange.get().state == "filtered"
+        assert self.db.NetworkChange.get().status_id == status_id
+        assert result == False
+
     def test_isTcpPortOpen_noRoute(self):
         ip = "127.0.0.1"
         port = 1234