Fix: Raise GvmError when the remote closed the connection on send

gvm/connections/_connection.py

@@ -82,11 +82,22 @@ def send(self, data: bytes) -> None:
 
         Args:
             data: Data to be send to the server as bytes.
+
+        Raises:
+            GvmError: If the socket is not connected or the remote server
+                has closed the connection. In the latter case the connection
+                needs to be re-established via :py:meth:`connect`.
         """
         if self._socket is None:
             raise GvmError("Socket is not connected")
 
-        self._socket.sendall(data)
+        try:
+            self._socket.sendall(data)
+        except ConnectionError as e:
+            # Connection was closed by server, e.g. after an error response
+            raise GvmError(
+                f"Remote closed the connection. Error was {e}"
+            ) from e
 
     def read(self) -> bytes:
         """Read data from the remote server
@@ -98,7 +109,13 @@ def read(self) -> bytes:
             time() + self._timeout if self._timeout is not None else None
         )
 
-        data = self._read()
+        try:
+            data = self._read()
+        except ConnectionError as e:
+            # Connection was reset by server
+            raise GvmError(
+                f"Remote closed the connection. Error was {e}"
+            ) from e
 
         if not data:
             # Connection was closed by server

tests/connections/test_gvm_connection.py

@@ -43,6 +43,50 @@ def test_read_no_data(self):
         with self.assertRaises(GvmError, msg="Remote closed the connection"):
             connection.read()
 
+    def test_read_connection_reset(self):
+        read_mock = MagicMock()
+        read_mock.side_effect = ConnectionResetError("Connection reset")
+
+        connection = DummyConnection()
+        connection._read = read_mock
+
+        with self.assertRaisesRegex(
+            GvmError, "^Remote closed the connection. Error was "
+        ):
+            connection.read()
+
+    def test_send_not_connected(self):
+        connection = DummyConnection()
+
+        with self.assertRaisesRegex(GvmError, "^Socket is not connected$"):
+            connection.send(b"<gmp/>")
+
+    def test_send_remote_closed(self):
+        for error in (
+            BrokenPipeError("Broken pipe"),
+            ConnectionResetError("Connection reset"),
+            ConnectionAbortedError("Connection aborted"),
+        ):
+            with self.subTest(error=type(error).__name__):
+                connection = DummyConnection()
+                connection._socket = MagicMock()
+                connection._socket.sendall.side_effect = error
+
+                with self.assertRaisesRegex(
+                    GvmError, "^Remote closed the connection. Error was "
+                ) as cm:
+                    connection.send(b"<gmp/>")
+
+                self.assertIs(cm.exception.__cause__, error)
+
+    def test_send_other_os_error_is_not_wrapped(self):
+        connection = DummyConnection()
+        connection._socket = MagicMock()
+        connection._socket.sendall.side_effect = TimeoutError("timed out")
+
+        with self.assertRaises(TimeoutError):
+            connection.send(b"<gmp/>")
+
     def test_read_trigger_timeout(self):
         # mocking the response into two parts, so we run into the timeout
         # check in the loop