re-throw BrokenPipeError as mpd.ConnectionError

Author: Marcel Jira

doc/changes.rst

@@ -11,6 +11,8 @@ Changes in v0.6.0 (unreleased)
 * Introduce MPDClientBase class which provides common MPD communication related
   helpers. Used as base for synchronous and asynchronous clients
 * port argument is optional when connecting via unix sockets
+* python-mpd will now raise mpd.ConnectionError instead of socket.error, when
+  connection is lost
 
 
 Changes in v0.5.5

mpd/base.py

@@ -463,8 +463,24 @@ def _execute(self, command, args, retval):
             return retval
 
     def _write_line(self, line):
-        self._wfile.write("{}\n".format(line))
-        self._wfile.flush()
+        try:
+            self._wfile.write("{}\n".format(line))
+            self._wfile.flush()
+        except socket.error as e:
+            error_message = "Connection to server was reset"
+            logger.info(error_message)
+            self._reset()
+            if IS_PYTHON2:
+                # Utilizing exec is not particularly elegant, however, it seems
+                # to be the only way as Python3 handles exceptions quite
+                # different to Python2. Without exec, the whole script is not
+                # executable in Python3. Also "six" does it the same way:
+                # https://bitbucket.org/gutworth/six/src/ (search "reraise")
+                exec('raise ConnectionError, "' + error_message + '",'
+                     'sys.exc_info()[2]')
+            else:
+                e = ConnectionError(error_message)
+                raise e.with_traceback(sys.exc_info()[2])
 
     def _write_command(self, command, args=[]):
         parts = [command]

mpd/tests.py

@@ -345,16 +345,28 @@ def test_set_timeout_from_connect(self):
             self.assertEqual(len(w), 1)
             self.assertIn('Use MPDClient.timeout', str(w[0].message))
 
+    @unittest.skipIf(sys.version_info < (3, 3), "BrokenPipeError was introduced in python 3.3")
+    def test_broken_pipe_error(self):
+        self.MPDWillReturn('volume: 63\n', 'OK\n')
+        self.client._wfile.write.side_effect = BrokenPipeError
+        self.socket_mock.error = Exception
+
+        with self.assertRaises(mpd.ConnectionError):
+            self.client.status()
+
     def test_connection_lost(self):
         # Simulate a connection lost: the socket returns empty strings
         self.MPDWillReturn('')
+        self.socket_mock.error = Exception
 
         with self.assertRaises(mpd.ConnectionError):
             self.client.status()
+            self.socket_mock.unpack.assert_called()
 
         # consistent behaviour, solves bug #11 (github)
         with self.assertRaises(mpd.ConnectionError):
             self.client.status()
+            self.socket_mock.unpack.assert_called()
 
         self.assertIs(self.client._sock, None)