1# (c) Stefan Countryman 

2 

3""" 

4Poll GraceDB for new superevents that have been marked EM_READY and have had a 

5GCN Notice VOEvent generated. Download and handle those GCN Notices. Runs as a 

6script checking for new VOEvents when called from the command line. 

7""" 

8 

9import os 

10from math import ceil 

11import logging 

12from llama.utils import ( 

13 DEFAULT_RUN_DIR, 

14 LOGDIR, 

15 COLOR, 

16) 

17from llama.event import Event 

18from llama.files.lvc_skymap import ( 

19 SKYMAP_FILENAMES, 

20 SkymapNotFoundError, 

21) 

22 

23GRACEDB_POLL_LOGFILE = os.path.join(LOGDIR, "llama.poll.gracedb.log") 

24LOGGER = logging.getLogger(__name__) 

25LOGGER.setLevel(logging.DEBUG) 

26 

27# number of seconds to look back; set to ~2 days 

28LOOKBACK = 2*10**5 

29 

30 

31def gpsnow(): 

32 """ 

33 Get the current GPS time (rounded up to the nearest integer for 

34 GraceDB's querying interface). 

35 """ 

36 import astropy 

37 return ceil(astropy.time.Time.now().gps) 

38 

39 

40def gracedb_query(gps, lookback=LOOKBACK): 

41 """ 

42 Get a GraceDB-compatible query string for finding recent superevents 

43 that happened in the last ``lookback`` seconds before the GPS time ``gps``. 

44 """ 

45 # TODO This doesn't work as advertised on 

46 # https://gracedb.ligo.org/documentation/queries.html 

47 return "label: EM_READY gpstime: {} .. {}".format(gps, gps-LOOKBACK) 

48 

49 

50def superevents(): 

51 """ 

52 Get a generator of superevents with skymaps that stops iterating once 

53 we've gone through all the events in the last ``LOOKBACK`` seconds. 

54 """ 

55 from llama.com.gracedb import GraceDb 

56 earliest_gps = gpsnow() - LOOKBACK 

57 for superevent in GraceDb().superevents("SKYMAP_READY"): 

58 if superevent['t_start'] < earliest_gps: 

59 return superevent 

60 yield superevent 

61 

62 

63def get_skymap_name(superevent): 

64 """Get candidate skymap filenames for this superevent dictionary.""" 

65 from llama.com.gracedb import GraceDb 

66 files = GraceDb().files(superevent['preferred_event']).json() 

67 for fname in files: 

68 if fname.endswith(".fits") or fname.endswith(".fits.gz"): 

69 if fname in SKYMAP_FILENAMES: 

70 return fname 

71 raise SkymapNotFoundError("Could not find skymap in {}".format(files)) 

72 

73 

74def fetch_recent(rundir=DEFAULT_RUN_DIR): 

75 """Fetch and store recent superevents.""" 

76 for superevent in superevents(): 

77 superid = superevent['superevent_id'] 

78 LOGGER.debug("Checking superevent: %s", superid) 

79 LOGGER.info("FAR: %s", superevent['far']) 

80 event = Event(superid, rundir=rundir) 

81 if event.exists(): 

82 LOGGER.info("Event directory exists for %s...", superid) 

83 if event.files.SkymapInfo.exists(): 

84 LOGGER.info("SkymapInfo exists for %s, SKIPPING.", superid) 

85 continue 

86 else: 

87 LOGGER.info(COLOR.blue("NEW SUPEREVENT: %s"), superid) 

88 LOGGER.debug("Initializing eventdir for %s", superid) 

89 event.init() 

90 LOGGER.debug("...done. Setting ROLE flag to observation.") 

91 event.flags['ROLE'] = 'observation' 

92 LOGGER.debug("...done. Making ``SkymapInfo`` for %s", superid) 

93 try: 

94 event.files.SkymapInfo.generate_from_gracedb_superevent( 

95 superid, 

96 get_skymap_name(superevent) 

97 ) 

98 except SkymapNotFoundError as err: 

99 LOGGER.error("No valid skymap found for %s: %s", superid, err) 

100 LOGGER.info(COLOR.green("Done with %s"), superid) 

101 # TODO add a VOEvent puller