api.py 文件源码

def api_has_bwctl(host, timeout=5, bind=None):
    """
    Determine if a host is running the BWCTL daemon
    """

    # Null implies localhost
    if host is None:
        host = "localhost"

    # HACK: BWTCLBC
    # If the environment says to bind to a certain address, do it.
    if bind is None:
        bind = os.environ.get('PSCHEDULER_LEAD_BIND_HACK', None)

    for family in [socket.AF_INET, socket.AF_INET6]:
        try:
            with closing(socket.socket(family, socket.SOCK_STREAM)) as sock:
                if bind is not None:
                    sock.bind((bind, 0))
                sock.settimeout(timeout)
                return sock.connect_ex((host, 4823)) == 0
        except socket.error:
            pass

    return False