docker_django_management.py 文件源码

def setup_docker_sigterm_handler():  # type: () -> None
    '''
    'manage.py runserver' is not set up to deal with a SIGTERM signal,
    and instead expects a Ctrl-C to come to its child process. So we'll
    add a SIGTERM handler here that finds all our children and gracefully
    shuts them down, which provides a quick graceful exit from Docker.
    '''

    def get_children():  # type: () -> Iterator[int]
        output = subprocess.check_output(
            "ps --ppid=%d -o pid | awk 'NR>1' | xargs echo" % os.getpid(),
            shell=True
        )
        return map(int, output.split())

    def handler(signum, frame):  # type: (int, Any) -> None
        for child_pid in get_children():
            try:
                os.kill(child_pid, signal.SIGTERM)
                os.waitpid(child_pid, 0)
            except OSError:
                pass
        sys.exit(0)

    info("Setting up Docker SIGTERM handler for quick, graceful exit.")
    signal.signal(signal.SIGTERM, handler)