Add proxy for running alongside QGroundControl

tools/pyflix/flix.py

@@ -53,9 +53,9 @@ class Flix:
         except OSError as e:
             if e.errno != errno.EADDRINUSE:
                 raise
-            # Port busy with QGC - using forwarding
+            # Port busy - using proxy
-            logger.debug('Listening on port 14445 (QGC forwarding)')
+            logger.debug('Listening on port 14560 (proxy)')
-            self.connection: mavutil.mavfile = mavutil.mavlink_connection('udpin:0.0.0.0:14445', source_system=254)  # type: ignore
+            self.connection: mavutil.mavfile = mavutil.mavlink_connection('udpin:0.0.0.0:14555', source_system=254)  # type: ignore
         self.connection.target_system = mav_id
         self.mavlink: mavlink.MAVLink = self.connection.mav
         self._event_listeners: dict[str, List[Callable[..., Any]]] = {}

tools/pyflix/proxy.py

@@ -0,0 +1,37 @@
+#!/usr/bin/env python3
+
+"""Proxy for running pyflix library alongside QGroundControl app."""
+
+import socket
+
+LOCAL = ('0.0.0.0', 14550)  # from Flix
+TARGETS = (
+    ('127.0.0.1', 14560),  # to QGroundControl
+    ('127.0.0.1', 14555),  # to pyflix
+)
+
+def main():
+    sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
+    sock.bind(LOCAL)
+
+    source_addr = None
+    packets = 0
+
+    print('Proxy started - run QGroundControl')
+
+    while True:
+        data, addr = sock.recvfrom(1024)  # read entire UDP packet
+        if addr in TARGETS:  # packet from target
+            if source_addr is None:
+                continue
+            sock.sendto(data, source_addr)
+        else:  # packet from source
+            source_addr = addr
+            for target in TARGETS:
+                sock.sendto(data, target)
+
+        packets += 1
+        print(f'\rPackets: {packets}', end='')
+
+if __name__ == '__main__':
+    main()

tools/pyproject.toml

@@ -10,6 +10,9 @@ dependencies = [
     "pymavlink",
 ]
 
+[project.scripts]
+flixproxy = "pyflix.proxy:main"
+
 [build-system]
 requires = ["setuptools>=61.0"]
 build-backend = "setuptools.build_meta"