Receive complete OSC UDP datagrams larger than 8192 bytes

pythonosc/osc_server.py

@@ -59,6 +59,9 @@ def _is_valid_request(request: _RequestType) -> bool:
 class OSCUDPServer(socketserver.UDPServer):
     """Superclass for different flavors of OSC UDP servers"""
 
+    # Receive complete UDP datagrams instead of socketserver's 8192-byte default.
+    max_packet_size = 65535
+
     def __init__(
         self,
         server_address: Tuple[str, int],

pythonosc/test/test_osc_server.py

@@ -2,7 +2,7 @@
 import unittest
 import unittest.mock
 
-from pythonosc import dispatcher, osc_server
+from pythonosc import dispatcher, osc_bundle_builder, osc_message_builder, osc_server
 
 _SIMPLE_PARAM_INT_MSG = b"/SYNC\x00\x00\x00,i\x00\x00\x00\x00\x00\x04"
 
@@ -114,6 +114,36 @@ def respond(*args, **kwargs):
 
 
 class TestOscUdpServer(unittest.TestCase):
+    @unittest.mock.patch("socket.socket")
+    def test_receive_large_datagrams(self, mock_socket_ctor):
+        message_builder = osc_message_builder.OscMessageBuilder("/large")
+        message_builder.add_arg(b"x" * 9000)
+        message = message_builder.build()
+        bundle_builder = osc_bundle_builder.OscBundleBuilder(
+            osc_bundle_builder.IMMEDIATELY
+        )
+        bundle_builder.add_content(message)
+        bundle = bundle_builder.build()
+        client_address = ("127.0.0.1", 8080)
+
+        for packet in (message, bundle):
+            with self.subTest(packet=type(packet).__name__):
+                # Model recvfrom's truncation when its buffer is too small.
+                mock_socket_ctor.return_value.recvfrom.side_effect = lambda size: (
+                    packet.dgram[:size],
+                    client_address,
+                )
+                callback = unittest.mock.Mock(return_value=None)
+                dispatch = dispatcher.Dispatcher()
+                dispatch.map("/large", callback)
+                with osc_server.BlockingOSCUDPServer(
+                    ("127.0.0.1", 0), dispatch
+                ) as server:
+                    request, address = server.get_request()
+                    self.assertEqual(request[0], packet.dgram)
+                    osc_server._UDPHandler(request, address, server)
+                    callback.assert_called_once_with("/large", b"x" * 9000)
+
     @unittest.mock.patch("socket.socket")
     def test_init_timeout(self, mock_socket_ctor):
         dispatcher = unittest.mock.Mock()