superbird-server.py

#!/usr/bin/env python3
import umsgpack
import time
import threading
import traceback
import common.sb_common as sb_c
import utils.handlers.bt_handler as bt_handler
import utils.wamp.wamp_handler as wamp_h
import utils.handlers.pubsub_handler as pubsub_handler
import utils.bt_utils as bt_utils

# Un-MessagePack messages and send them to their respective handlers
def processMsg(data: bytearray):
    try:
        send = False
        with_event = False
        msg = umsgpack.unpackb(data)
        msg_opcode = sb_c.opCodes(msg[0])
        match msg_opcode:
            case sb_c.opCodes.HELLO: # More info in superbird_util.py
                send, resp, with_event, event = wamp_h.hello_handler(msg)
            case sb_c.opCodes.AUTHENTICATE:
                send, resp, with_event, event = wamp_h.authenticate_handler()
            case sb_c.opCodes.CALL: # More info in superbird_util.py
                send, resp, with_event, event = wamp_h.function_handler(msg)
            case sb_c.opCodes.SUBSCRIBE: # More info in superbird_util.py
                send, resp, with_event, event = wamp_h.subscribe_handler(msg)
            case sb_c.opCodes.UNSUBSCRIBE: 
                send, resp, with_event, event = wamp_h.subscribe_handler(msg, True)
            case _:
                print("Unhandled opcode:", msg_opcode, " Msg:", msg)
        if send:
            bt_handler.addToOutbox(resp)
        if with_event:
            pubsub_handler.update_status()
        # if with_event: # Sometimes we also need to send an event # Might not be needed
        #     bt_handler.addToOutbox(event)
    except Exception:
        print("\n\n~~~~~ Exception Start ~~~~~")
        traceback.print_exc()
        print("~~~~~  Exception End  ~~~~~\n")
        pass

def resetVars():
    wamp_h.last_subscription = 63
    sb_c.superbird_session = {}
    pubsub_handler.pub_id = 1

connected = False
registered = False
stopThreads = threading.Event()
while True:
    if not connected:
        # We advertise the RFCOMM service that Superbird is expecting and accept any connections to it
        server_sock = bt_utils.open_socket()
        time.sleep(1)
        while not registered: # We just need to register the service once
            bt_utils.register_sdp()
            print("Waiting for connection on RFCOMM channel", bt_utils.port)
            registered = True
        client_sock, client_info = server_sock.accept()
        print("Connected")
        outbox_thread = threading.Thread(target=bt_handler.outboxThread, args=(client_sock, stopThreads,), daemon=True)
        sub_handler_thread = threading.Thread(target=pubsub_handler.subHandlerThread, args=(stopThreads,), daemon=True)
        # Start outbox thread
        outbox_thread.start()
        # Start subscription handler thread
        sub_handler_thread.start()
        connected = True

    if connected:
        try:
            while True:
                data = bt_handler.get_msg(client_sock)
                processMsg(data)
                if not data:
                    break
        except KeyboardInterrupt:
            pass
        except Exception:
            print("\n\n~~~~~ Exception Start ~~~~~")
            traceback.print_exc()
            print("~~~~~  Exception End  ~~~~~\n")
            pass
        client_sock.close()
        stopThreads.set()
        time.sleep(2) #allow time for threads to stop
        server_sock.close()
        client_sock.close()
        connected = False
        resetVars()
        print("\n\nDisconnected. Reopening socket in 5s. Press Ctrl + C to stop")
        try:
            time.sleep(5)
            stopThreads.clear()
        except KeyboardInterrupt:
            print("Quitting...")
            raise SystemExit(0)