tests/ocpp-server/server.py

   1 import asyncio
   2 import logging
   3 from datetime import datetime, timezone
   4 from typing import Sequence
   5
   6 import websockets
   7 from ocpp.routing import on
   8 from ocpp.v201 import ChargePoint as cp
   9 from ocpp.v201 import call_result
  10 from ocpp.v201.enums import RegistrationStatusType
  11
  12 # Setting up the logging configuration to display debug level messages.
  13 logging.basicConfig(level=logging.DEBUG)
  14
  15
  16 # Define a ChargePoint class inheriting from the OCPP 2.0.1 ChargePoint class.
  17 class ChargePoint(cp):
  18     # Message handlers to receive OCPP message.
  19     @on('BootNotification')
  20     async def on_boot_notification(self, charging_station, reason, **kwargs):
  21         logging.info("Received BootNotification")
  22         # Create and return a BootNotification response with the current time,
  23         # an interval of 10 seconds, and an accepted status.
  24         return call_result.BootNotification(
  25             current_time=datetime.now(timezone.utc).isoformat(),
  26             interval=10,
  27             status=RegistrationStatusType.accepted
  28         )
  29
  30     # Request handlers to emit OCPP messages.
  31
  32
  33 # Function to handle new WebSocket connections.
  34 async def on_connect(websocket, path):
  35     """ For every new charge point that connects, create a ChargePoint instance and start
  36     listening for messages."""
  37     try:
  38         requested_protocols = websocket.request_headers['Sec-WebSocket-Protocol']
  39     except KeyError:
  40         logging.info("Client hasn't requested any Subprotocol. Closing Connection")
  41         return await websocket.close()
  42
  43     if websocket.subprotocol:
  44         logging.info("Protocols Matched: %s", websocket.subprotocol)
  45     else:
  46         logging.warning('Protocols Mismatched | Expected Subprotocols: %s,'
  47                         ' but client supports %s | Closing connection',
  48                         websocket.available_subprotocols,
  49                         requested_protocols)
  50         return await websocket.close()
  51
  52     charge_point_id = path.strip('/')
  53     cp = ChargePoint(charge_point_id, websocket)
  54
  55     # Start the ChargePoint instance to listen for incoming messages.
  56     await cp.start()
  57
  58
  59 # Main function to start the WebSocket server.
  60 async def main():
  61     # Create the WebSocket server and specify the handler for new connections.
  62     server = await websockets.serve(
  63         on_connect,
  64         '127.0.0.1',  # Listen on loopback.
  65         9000,  # Port number.
  66         subprotocols=Sequence['ocpp2.0', 'ocpp2.0.1']  # Specify OCPP 2.0.1 subprotocols.
  67     )
  68     logging.info("WebSocket Server Started")
  69     # Wait for the server to close (runs indefinitely).
  70     await server.wait_closed()
  71
  72
  73 # Entry point of the script.
  74 if __name__ == '__main__':
  75     # Run the main function to start the server.
  76     asyncio.run(main())