Polish mrbridge and add ftpserve

mrbridge.py

@@ -4,12 +4,29 @@ import threading
 import time
 import websocket
 
+kDefaultSerialPort = None
+kDefaultBaudrate = 115200
+
+
+def getserial(port=None, baudrate=None, **kwargs):
+    if port is not None:
+        return serial.Serial(port, baudrate)
+
+    # return first /dev/ttyACMx found
+    for i in range(10):
+        try:
+            return serial.Serial(f"/dev/ttyACM{i}", baudrate)
+        except serial.SerialException:
+            pass
+    raise RuntimeError("No serial device available.")
+
 
 def parse_args():
     parser = argparse.ArgumentParser(description="Bridge a serial port to a websocket")
-    parser.add_argument("port", help="path to the serial port")
-    parser.add_argument("--baudrate", default=115200)
-    parser.add_argument("--escape", action='store_true')
+    parser.add_argument(
+        "--port", help="path to the serial port", default=kDefaultSerialPort
+    )
+    parser.add_argument("--baudrate", default=kDefaultBaudrate)
     parser.add_argument("ws", help="URL of the websocket")
     return parser.parse_args()
 
@@ -28,28 +45,23 @@ def slowwrite(device, data):
 
 def ws_thread(device, ws):
     while True:
-        data = ws.recv();
-        slowwrite(device, data.replace(b'\n', b'\r\n'))
+        data = ws.recv()
+        slowwrite(device, data.replace(b"\n", b"\r\n"))
 
 
 def main():
     args = parse_args()
-    device = serial.Serial(args.port, baudrate=args.baudrate)
+    device = getserial(**vars(args))
     ws = websocket.create_connection(args.ws)
 
     wst = threading.Thread(target=ws_thread, args=(device, ws), daemon=True)
     wst.start()
 
-    if args.escape:
-        device.write([0x03])
-    try:
-        device_thread(device, ws)
-    except KeyboardInterrupt:
-        pass
-    finally:
-        if args.escape:
-            device.write([0x02])
+    device_thread(device, ws)
 
 
 if __name__ == "__main__":
-    main()
+    try:
+        main()
+    except KeyboardInterrupt:
+        pass