tests/ocpp-server/server.py

   1 import asyncio
   2 import logging
   3 from datetime import datetime, timezone
   4 from threading import Timer
   5
   6 import ocpp.v201
   7 import websockets
   8 from ocpp.routing import on
   9 from ocpp.v201.enums import (
  10     Action,
  11     AuthorizationStatusType,
  12     ClearCacheStatusType,
  13     RegistrationStatusType,
  14     TransactionEventType,
  15 )
  16 from websockets import ConnectionClosed
  17
  18 # Setting up the logging configuration to display debug level messages.
  19 logging.basicConfig(level=logging.DEBUG)
  20
  21 ChargePoints = set()
  22
  23
  24 class RepeatTimer(Timer):
  25     """Class that inherits from the Timer class. It will run a
  26     function at regular intervals."""
  27
  28     def run(self):
  29         while not self.finished.wait(self.interval):
  30             self.function(*self.args, **self.kwargs)
  31
  32
  33 # Define a ChargePoint class inheriting from the OCPP 2.0.1 ChargePoint class.
  34 class ChargePoint(ocpp.v201.ChargePoint):
  35     def __init__(self, charge_point_id, connection):
  36         super().__init__(self, charge_point_id, connection)
  37         self._ws_ping_timer = RepeatTimer(60, self.web_socket_ping)
  38         self._ws_ping_timer.start()
  39
  40     def stop(self):
  41         self._ws_ping_timer.cancel()
  42
  43     def web_socket_ping(self):
  44         try:
  45             self._connection.ping()
  46         except ConnectionClosed:
  47             ChargePoints.remove(self)
  48             self.stop()
  49
  50     # Message handlers to receive OCPP messages.
  51     @on(Action.BootNotification)
  52     async def on_boot_notification(self, charging_station, reason, **kwargs):
  53         logging.info("Received BootNotification")
  54         # Create and return a BootNotification response with the current time,
  55         # an interval of 60 seconds, and an accepted status.
  56         return ocpp.v201.call_result.BootNotification(
  57             current_time=datetime.now(timezone.utc).isoformat(),
  58             interval=60,
  59             status=RegistrationStatusType.accepted,
  60         )
  61
  62     @on(Action.Heartbeat)
  63     async def on_heartbeat(self, **kwargs):
  64         logging.info("Received Heartbeat")
  65         return ocpp.v201.call_result.Heartbeat(
  66             current_time=datetime.now(timezone.utc).isoformat()
  67         )
  68
  69     @on(Action.StatusNotification)
  70     async def on_status_notification(
  71         self, timestamp, evse_id: int, connector_id: int, connector_status, **kwargs
  72     ):
  73         logging.info("Received StatusNotification")
  74         return ocpp.v201.call_result.StatusNotification()
  75
  76     @on(Action.Authorize)
  77     async def on_authorize(self, id_token, **kwargs):
  78         logging.info("Received Authorize")
  79         return ocpp.v201.call_result.Authorize(
  80             id_token_info={"status": AuthorizationStatusType.accepted}
  81         )
  82
  83     @on(Action.TransactionEvent)
  84     async def on_transaction_event(
  85         self,
  86         event_type: TransactionEventType,
  87         timestamp,
  88         trigger_reason,
  89         seq_no: int,
  90         transaction_info,
  91         **kwargs,
  92     ):
  93         match event_type:
  94             case TransactionEventType.started:
  95                 logging.info("Received TransactionEvent Started")
  96                 return ocpp.v201.call_result.TransactionEvent(
  97                     id_token_info={"status": AuthorizationStatusType.accepted}
  98                 )
  99             case TransactionEventType.updated:
 100                 logging.info("Received TransactionEvent Updated")
 101                 return ocpp.v201.call_result.TransactionEvent(total_cost=10)
 102             case TransactionEventType.ended:
 103                 logging.info("Received TransactionEvent Ended")
 104                 return ocpp.v201.call_result.TransactionEvent()
 105
 106     @on(Action.MeterValues)
 107     async def on_meter_values(self, evse_id: int, meter_value, **kwargs):
 108         logging.info("Received MeterValues")
 109         return ocpp.v201.call_result.MeterValues()
 110
 111     # Request handlers to emit OCPP messages.
 112     async def send_clear_cache(self):
 113         request = ocpp.v201.call.ClearCache()
 114         response = await self.call(request)
 115
 116         if response.status == ClearCacheStatusType.accepted:
 117             logging.info("Cache clearing successful")
 118         else:
 119             logging.info("Cache clearing failed")
 120
 121
 122 # Function to handle new WebSocket connections.
 123 async def on_connect(websocket, path):
 124     """For every new charge point that connects, create a ChargePoint instance and start
 125     listening for messages."""
 126     try:
 127         requested_protocols = websocket.request_headers["Sec-WebSocket-Protocol"]
 128     except KeyError:
 129         logging.info("Client hasn't requested any Subprotocol. Closing Connection")
 130         return await websocket.close()
 131
 132     if websocket.subprotocol:
 133         logging.info("Protocols Matched: %s", websocket.subprotocol)
 134     else:
 135         logging.warning(
 136             "Protocols Mismatched | Expected Subprotocols: %s,"
 137             " but client supports %s | Closing connection",
 138             websocket.available_subprotocols,
 139             requested_protocols,
 140         )
 141         return await websocket.close()
 142
 143     charge_point_id = path.strip("/")
 144     cp = ChargePoint(charge_point_id, websocket)
 145     ChargePoints.add(cp)
 146
 147     # Start the ChargePoint instance to listen for incoming messages.
 148     await cp.start()
 149
 150
 151 # Main function to start the WebSocket server.
 152 async def main():
 153     # Create the WebSocket server and specify the handler for new connections.
 154     server = await websockets.serve(
 155         on_connect,
 156         "127.0.0.1",  # Listen on loopback.
 157         9000,  # Port number.
 158         subprotocols=["ocpp2.0", "ocpp2.0.1"],  # Specify OCPP 2.0.1 subprotocols.
 159     )
 160     logging.info("WebSocket Server Started")
 161     # Wait for the server to close (runs indefinitely).
 162     await server.wait_closed()
 163
 164
 165 # Entry point of the script.
 166 if __name__ == "__main__":
 167     # Run the main function to start the server.
 168     asyncio.run(main())