a python server accepting MLLP-wrapped requests for PANACEA IMP

mllp_panacea_imp.py

import socket
import threading
import socketserver
import sys
import time

def send_command(command:str)->str:
    HOST = '127.0.0.1'
    PORT = 27016
    with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
        s.connect((HOST, PORT))
        s.sendall(command.encode('utf-8'))
        data = []
        while True:
            msg = s.recv(1024)
            if not msg:
                break
            print(f"Got '{msg}'")
            data.append(msg.decode("utf-8", "strict"))
        return "\n".join(data)

def debug(msg:str):
    print('\033[32m' + msg+ '\033[0m', file=sys.stderr)

tries = [min(2, i) for i in range(1, 8)]

def acquire_credentials():
    response = send_command('Launch capture')
    if response == 'command received':
        debug('Capture cmd submitted.. polling for result')
        response = send_command('Matching result')
        for k, t in enumerate(tries):
            debug(f"Try {k+1}, got '{response}'")
            if response != "0":
                [username, password] = response.splitlines()[:2]
                print(f"Username: {username} Password: '{password}'")
                return (username, password)
            debug(f"Sleeping for {t} seconds")
            time.sleep(t)
            response = send_command('Matching result')
    else:
        debug(f"Error, got '{response}'")
    send_command("Stop capture")
    return None

HOST = ''
PORT = 27017


header = b'\x0b'
trailer = b'\x1c\x0d'
class ThreadedTCPRequestHandler(socketserver.BaseRequestHandler):
    def handle(self):
        while True:
            req = self.request.recv(1024)
            if not req:
                return
            msg = req.removeprefix(header).removesuffix(trailer).decode()
            print(f"Got {msg}")
            creds = acquire_credentials()
            if creds:
                data = "\n".join(creds)
            else:
                data = ""
            response = bytearray(header) + bytearray(data.encode("utf-8")) + bytearray(trailer)
            self.request.sendall(response)

class ThreadedTCPServer(socketserver.ThreadingMixIn, socketserver.TCPServer):
    pass

def client(port, message):
    with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as sock:
        sock.connect(('127.0.0.1', port))
        sock.sendall(bytearray(header) + bytearray(message.encode("utf-8")) + bytearray(trailer))
        response = sock.recv(1024).removeprefix(header).removesuffix(trailer).decode()
        print("Received: {}".format(response))

if __name__ == "__main__":
    server = ThreadedTCPServer((HOST, PORT), ThreadedTCPRequestHandler)
    with server:
        ip, port = server.server_address
        print(f"Server started in {ip}:{port}")

        server.serve_forever()