main.py

import os
import signal
import sys
import time
from concurrent import futures

import grpc
from pbr.version import VersionInfo

from server import backgroundworker
from server import config
from server import log
from server import server_pb2_grpc
from server.character import CharacterManager
from server.session import Session

_v = VersionInfo('main').semantic_version()
__version__ = _v.release_string()
version_info = _v.version_tuple()


class GracefulKiller:
    kill_now = False

    def __init__(self):
        signal.signal(signal.SIGINT, self.exit_gracefully)
        signal.signal(signal.SIGTERM, self.exit_gracefully)

    def exit_gracefully(self, signum, frame):
        self.kill_now = True


def serve():
    killer = GracefulKiller()
    logger = log.setup_custom_logger("cos301-DND")

    if os.getuid() == 0:
        sys.exit("Should not be run as root!")

    logger.info("Starting...")

    logger.info("Version: " + __version__)

    if os.environ["ENV"] == "prod":
        logger.info("In production environment!")
    else:
        logger.info("In development environment!")

    # Change between development environment and production.
    # In production
    server = grpc.server(futures.ThreadPoolExecutor(max_workers=int(config.val['server']['max_worker_threads'])))
    server_pb2_grpc.add_SessionsManagerServicer_to_server(Session(), server)
    server_pb2_grpc.add_CharactersManagerServicer_to_server(CharacterManager(), server)
    server.add_insecure_port("[::]:50051")
    server.start()

    # Background daemon
    bw = backgroundworker.BackgroundWorker()
    bw.start()

    logger.info("Started!")

    try:
        while True:
            if killer.kill_now:
                logger.info("Received kill, stopping...")
                break
            time.sleep(1)

    except KeyboardInterrupt:
        server.stop(0)
        logger.info("Stopped!")
    finally:
        server.stop(0)
        logger.info("Stopped!")


if __name__ == "__main__":
    serve()