Files
drb-core-server/app/server.py
2025-05-11 20:33:57 -04:00

203 lines
7.7 KiB
Python

import asyncio
import websockets
import json
import uuid
from quart import Quart, jsonify, request
from routers.systems import systems_bp
# --- WebSocket Server Components ---
# Dictionary to store active clients: {client_id: websocket}
active_clients = {}
async def register_client(websocket, client_id):
"""Registers a new client connection."""
active_clients[client_id] = websocket
print(f"Client {client_id} connected.")
async def unregister_client(client_id):
"""Unregisters a disconnected client."""
if client_id in active_clients:
del active_clients[client_id]
print(f"Client {client_id} disconnected.")
async def send_command_to_client(client_id, command_name, *args):
"""Sends a command to a specific client."""
if client_id in active_clients:
websocket = active_clients[client_id]
message = json.dumps({"type": "command", "name": command_name, "args": args})
try:
await websocket.send(message)
print(f"Sent command '{command_name}' to client {client_id}")
except websockets.exceptions.ConnectionClosedError:
print(f"Failed to send to client {client_id}: connection closed.")
await unregister_client(client_id)
else:
print(f"Client {client_id} not found.")
async def send_command_to_all_clients(command_name, *args):
"""Sends a command to all connected clients."""
message = json.dumps({"type": "command", "name": command_name, "args": args})
# Use a list of items to avoid issues if clients disconnect during iteration
clients_to_send = list(active_clients.items())
for client_id, websocket in clients_to_send:
try:
await websocket.send(message)
print(f"Sent command '{command_name}' to client {client_id}")
except websockets.exceptions.ConnectionClosedError:
print(f"Failed to send to client {client_id}: connection closed.")
await unregister_client(client_id)
async def websocket_server_handler(websocket):
"""Handles incoming WebSocket connections and messages from clients."""
client_id = None
try:
# Handshake: Receive the first message which should contain the client ID
handshake_message = await websocket.recv()
handshake_data = json.loads(handshake_message)
if handshake_data.get("type") == "handshake" and "id" in handshake_data:
client_id = handshake_data["id"]
await register_client(websocket, client_id)
await websocket.send(json.dumps({"type": "handshake_ack", "status": "success"})) # Acknowledge handshake
# Keep the connection alive and listen for potential messages from the client
# (Though in this server-commanded model, clients might not send much)
# We primarily wait for the client to close the connection
await websocket.wait_closed()
else:
print(f"Received invalid handshake from {websocket.remote_address}. Closing connection.")
await websocket.close()
except websockets.exceptions.ConnectionClosedError:
print(f"Client connection closed unexpectedly for {client_id}.")
except json.JSONDecodeError:
print(f"Received invalid JSON from {client_id or 'an unknown client'}.")
except Exception as e:
print(f"An error occurred with client {client_id}: {e}")
finally:
if client_id:
await unregister_client(client_id)
# --- Radio Channel Data (Placeholder) ---
# In a real app, this would likely come from a database
channels = {
"channel_1": {
"id": "channel_1",
"name": "Local News Radio",
"frequency_list_khz": ["98500"],
"decode_mode": "P25",
"location": "Cityville",
"tags": [],
"tag_whitelist": [1,2,3],
"avail_on_nodes": ["client-abc123", "client-def456"], # List of client IDs that can tune this channel
"description": "Your source for local news and weather."
},
"channel_2": {
"id": "channel_2",
"name": "Music Mix FM",
"frequency_list_khz": [101300],
"decode_mode": "P25",
"location": "Townsville",
"tags": [],
"tag_whitelist": [6,7,8],
"avail_on_nodes": ["client-def456", "client-ghi789"],
"description": "Playing the hits, all day long."
}
# Add more channels here
}
# --- Quart API Components ---
app = Quart(__name__)
# Store the websocket server instance
websocket_server_instance = None
@app.before_serving
async def startup_websocket_server():
"""Starts the WebSocket server when the Quart app starts."""
global websocket_server_instance
websocket_server_address = "0.0.0.0"
websocket_server_port = 8765
# Start the WebSocket server task
websocket_server_instance = await websockets.serve(
websocket_server_handler,
websocket_server_address,
websocket_server_port
)
print(f"WebSocket server started on ws://{websocket_server_address}:{websocket_server_port}")
@app.after_serving
async def shutdown_websocket_server():
"""Shuts down the WebSocket server when the Quart app stops."""
global websocket_server_instance
if websocket_server_instance:
websocket_server_instance.close()
await websocket_server_instance.wait_closed()
print("WebSocket server shut down.")
app.register_blueprint(systems_bp, url_prefix="/systems")
@app.route('/')
async def index():
return "Welcome to the Radio App Server API!"
@app.route('/clients', methods=['GET'])
async def list_clients():
"""API endpoint to list currently connected client IDs."""
return jsonify(list(active_clients.keys()))
@app.route('/request_token', methods=['POST'])
async def request_token():
"""API endpoint to list currently connected client IDs."""
# TODO - Add DB logic
return jsonify({
"token": "MTE5NjAwNTM2ODYzNjExMjk3Nw.GuCMXg.24iNNofNNumq46FIj68zMe9RmQgugAgfrvelEA"
})
# --- Example API endpoint to trigger a WebSocket command ---
# This is a simple example. More complex logic might be needed
# to validate commands or arguments before sending.
@app.route('/command/<client_id>/<command_name>', methods=['POST'])
async def api_send_command(client_id, command_name):
"""
API endpoint to send a command to a specific client via WebSocket.
Expects JSON body with 'args': [...]
e.g., POST to /command/client-abc123/print_message with body {"args": ["Hello!"]}
"""
if client_id not in active_clients:
return jsonify({"error": f"Client {client_id} not found"}), 404
# if command_name not in ["join_server", "leave_server", "set_status", "run_task"]: # Basic validation
# return jsonify({"error": f"Unknown command: {command_name}"}), 400
try:
request_data = await request.get_json()
args = request_data.get("args", [])
if not isinstance(args, list):
return jsonify({"error": "'args' must be a list"}), 400
# Send the command asynchronously
await send_command_to_client(client_id, command_name, *args)
return jsonify({"status": "command sent", "client_id": client_id, "command": command_name}), 200
except Exception as e:
return jsonify({"error": f"Failed to send command: {e}"}), 500
# --- Main Execution ---
if __name__ == "__main__":
# Quart's app.run() will start the asyncio event loop and manage it.
# The @app.before_serving decorator ensures the websocket server starts within that loop.
# We removed asyncio.run(main()) and the main() function itself.
print("Starting Quart API server...")
app.run(
host="0.0.0.0",
port=5000,
debug=False # Set to True for development
)
print("Quart API server stopped.")