1# (c) Stefan Countryman, 2019 

2 

3""" 

4Launch the GCN Notice listener. 

5""" 

6 

7import os 

8import logging 

9import gcn 

10from llama.utils import ( 

11 __version__, 

12 LOGDIR, 

13) 

14from llama.listen import Parsers as ListenParsers 

15from llama.cli import Parsers 

16from llama.listen.gcn import ( 

17 LlamaHandlers, 

18 GCN_ARCHIVE, 

19 DEFAULT_HOST, 

20 PUBLIC_GCN_PORT, 

21 PRIVATE_GCN_PORT, 

22) 

23from llama.cli import ( 

24 log_exceptions_and_recover, 

25 get_logging_cli, 

26 CliParser, 

27) 

28 

29GCN_LOGFILE = os.path.join(LOGDIR, 'gcn.log') 

30LOGGER = logging.getLogger(__name__) 

31 

32# TODO Handle loggers properly as part of a unified daemonizing procedure. 

33 

34 

35def get_parser(): 

36 """Get CLI.""" 

37 parser = CliParser( 

38 description=__doc__, 

39 parents=( 

40 get_logging_cli(GCN_LOGFILE, 'debug'), 

41 ListenParsers.rundir, 

42 Parsers.erralert, 

43 ), 

44 ) 

45 parser.add_argument("-L", "--lvc-private", action="store_true", help=""" 

46 If provided, listen for private LIGO GCN circulars on port 8099. This 

47 argument will OVERRIDE the -p/--port argument.""") 

48 parser.add_argument("-g", "--gcn-archive", default=GCN_ARCHIVE, help=""" 

49 Change the GCN archive directory (i.e. where all GCN Notices are 

50 archived too for recordkeeping). Creates the directory if it does not 

51 already exist.""") 

52 parser.add_argument("-i", "--host", default=DEFAULT_HOST, help=""" 

53 The host to listen to. Defaults to the main GCN server: 

54 {}""".format(DEFAULT_HOST)) 

55 parser.add_argument("-p", "--port", default=PUBLIC_GCN_PORT, help=""" 

56 The port on the GCN server to connect to. Default: 

57 {}""".format(PUBLIC_GCN_PORT)) 

58 return parser 

59 

60 

61def main(): 

62 """Run a GCN VOEvent listener with ``all_llama_handlers``.""" 

63 parser = get_parser() 

64 args = parser.parse_args() 

65 if args.lvc_private: 

66 args.port = PRIVATE_GCN_PORT 

67 for opt in 'rundir', 'gcn_archive': 

68 dirpath = getattr(args, opt) 

69 if not os.path.isdir(dirpath): 

70 LOGGER.info("specified %s does not exist, creating: %s", 

71 opt, dirpath) 

72 os.makedirs(dirpath) 

73 # pylint: disable=no-member 

74 LOGGER.info("Starting GCN Listener, llama version %s.", __version__) 

75 handler = log_exceptions_and_recover()( 

76 LlamaHandlers(rundir=args.rundir, gcn_archive=args.gcn_archive) 

77 ) 

78 gcn.listen(host=args.host, port=args.port, handler=handler) 

79 

80 

81if __name__ == "__main__": 

82 main()