initial commit

Author: ruthwikdasyam

dimos/teleop/phone/web/fastapi_server.py

@@ -0,0 +1,118 @@
+#!/usr/bin/env python3
+# Copyright 2025-2026 Dimensional Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""
+Phone Teleop FastAPI Server.
+
+Replaces the Deno WebSocket-to-LCM bridge with a Python FastAPI server.
+Extends RobotWebInterface to serve the phone teleop web app and forward
+WebSocket binary LCM packets to the LCM network via UDP multicast.
+"""
+
+from __future__ import annotations
+
+from pathlib import Path
+import socket
+import struct
+
+from fastapi import WebSocket, WebSocketDisconnect
+from fastapi.responses import HTMLResponse
+from fastapi.staticfiles import StaticFiles
+
+from dimos.utils.logging_config import setup_logger
+from dimos.web.robot_web_interface import RobotWebInterface
+
+logger = setup_logger()
+
+# LCM default multicast group and port
+LCM_MULTICAST_GROUP = "239.255.76.67"
+LCM_MULTICAST_PORT = 7667
+
+STATIC_DIR = Path(__file__).parent / "static"
+
+
+class PhoneTeleopServer(RobotWebInterface):
+    """Phone teleoperation server built on RobotWebInterface.
+
+    Adds a WebSocket endpoint that bridges binary LCM packets from the
+    phone browser to the LCM UDP multicast network.
+    """
+
+    def __init__(
+        self,
+        port: int = 8444,
+        lcm_multicast_group: str = LCM_MULTICAST_GROUP,
+        lcm_multicast_port: int = LCM_MULTICAST_PORT,
+    ) -> None:
+        super().__init__(port=port)
+        self.lcm_multicast_group = lcm_multicast_group
+        self.lcm_multicast_port = lcm_multicast_port
+        self._udp_sock: socket.socket | None = None
+
+        self._setup_teleop_routes()
+
+    # ------------------------------------------------------------------
+    # LCM UDP socket
+    # ------------------------------------------------------------------
+
+    def _ensure_udp_socket(self) -> socket.socket:
+        """Create (or reuse) a UDP socket for LCM multicast publishing."""
+        if self._udp_sock is None:
+            sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM, socket.IPPROTO_UDP)
+            sock.setsockopt(socket.IPPROTO_IP, socket.IP_MULTICAST_TTL, struct.pack("b", 1))
+            self._udp_sock = sock
+            logger.info("LCM UDP multicast socket created")
+        return self._udp_sock
+
+    def _publish_lcm_packet(self, data: bytes) -> None:
+        """Send a raw LCM packet to the multicast group."""
+        sock = self._ensure_udp_socket()
+        sock.sendto(data, (self.lcm_multicast_group, self.lcm_multicast_port))
+
+    # ------------------------------------------------------------------
+    # Routes
+    # ------------------------------------------------------------------
+
+    def _setup_teleop_routes(self) -> None:
+        """Add phone-teleop-specific routes on top of the base interface."""
+
+        @self.app.get("/teleop", response_class=HTMLResponse)
+        async def teleop_index() -> HTMLResponse:
+            index_path = STATIC_DIR / "index.html"
+            return HTMLResponse(content=index_path.read_text())
+
+        if STATIC_DIR.is_dir():
+            self.app.mount("/static", StaticFiles(directory=str(STATIC_DIR)), name="teleop_static")
+
+        @self.app.websocket("/ws")
+        async def websocket_endpoint(ws: WebSocket) -> None:
+            await ws.accept()
+            logger.info("Phone client connected")
+            try:
+                while True:
+                    data = await ws.receive_bytes()
+                    try:
+                        self._publish_lcm_packet(data)
+                    except Exception:
+                        logger.exception("Failed to forward LCM packet")
+            except WebSocketDisconnect:
+                logger.info("Phone client disconnected")
+            except Exception:
+                logger.exception("WebSocket error")
+
+
+if __name__ == "__main__":
+    server = PhoneTeleopServer()
+    server.run()