logging_utils.py

   1 #!/usr/bin/env python3
   2
   3 """Utilities related to logging."""
   4
   5 import contextlib
   6 import datetime
   7 import logging
   8 from logging.handlers import RotatingFileHandler, SysLogHandler
   9 import os
  10 import pytz
  11 import sys
  12
  13 import argparse_utils
  14 import config
  15
  16 cfg = config.add_commandline_args(
  17     f'Logging ({__file__})',
  18     'Args related to logging')
  19 cfg.add_argument(
  20     '--logging_config_file',
  21     type=argparse_utils.valid_filename,
  22     default=None,
  23     metavar='FILENAME',
  24     help='Config file containing the logging setup, see: https://docs.python.org/3/howto/logging.html#logging-advanced-tutorial',
  25 )
  26 cfg.add_argument(
  27     '--logging_level',
  28     type=str,
  29     default='INFO',
  30     choices=['NOTSET', 'DEBUG', 'INFO', 'WARNING', 'ERROR', 'CRITICAL'],
  31     metavar='LEVEL',
  32     help='The level below which to squelch log messages.',
  33 )
  34 cfg.add_argument(
  35     '--logging_format',
  36     type=str,
  37     default='%(levelname)s:%(asctime)s: %(message)s',
  38     help='The format for lines logged via the logger module.'
  39 )
  40 cfg.add_argument(
  41     '--logging_date_format',
  42     type=str,
  43     default='%Y/%m/%dT%H:%M:%S.%f%z',
  44     metavar='DATEFMT',
  45     help='The format of any dates in --logging_format.'
  46 )
  47 cfg.add_argument(
  48     '--logging_console',
  49     action=argparse_utils.ActionNoYes,
  50     default=True,
  51     help='Should we log to the console (stderr)',
  52 )
  53 cfg.add_argument(
  54     '--logging_filename',
  55     type=str,
  56     default=None,
  57     metavar='FILENAME',
  58     help='The filename of the logfile to write.'
  59 )
  60 cfg.add_argument(
  61     '--logging_filename_maxsize',
  62     type=int,
  63     default=(1024*1024),
  64     metavar='#BYTES',
  65     help='The maximum size (in bytes) to write to the logging_filename.'
  66 )
  67 cfg.add_argument(
  68     '--logging_filename_count',
  69     type=int,
  70     default=2,
  71     metavar='COUNT',
  72     help='The number of logging_filename copies to keep before deleting.'
  73 )
  74 cfg.add_argument(
  75     '--logging_syslog',
  76     action=argparse_utils.ActionNoYes,
  77     default=False,
  78     help='Should we log to localhost\'s syslog.'
  79 )
  80 cfg.add_argument(
  81     '--logging_debug_threads',
  82     action=argparse_utils.ActionNoYes,
  83     default=False,
  84     help='Should we prepend pid/tid data to all log messages?'
  85 )
  86 cfg.add_argument(
  87     '--logging_info_is_print',
  88     action=argparse_utils.ActionNoYes,
  89     default=False,
  90     help='logging.info also prints to stdout.'
  91 )
  92
  93
  94 class OnlyInfoFilter(logging.Filter):
  95     def filter(self, record):
  96         return record.levelno == logging.INFO
  97
  98
  99 class MillisecondAwareFormatter(logging.Formatter):
 100     converter = datetime.datetime.fromtimestamp
 101
 102     def formatTime(self, record, datefmt=None):
 103         ct = self.converter(record.created, pytz.timezone("US/Pacific"))
 104         if datefmt:
 105             s = ct.strftime(datefmt)
 106         else:
 107             t = ct.strftime("%Y-%m-%d %H:%M:%S")
 108             s = "%s,%03d" % (t, record.msecs)
 109         return s
 110
 111
 112 def initialize_logging(logger=None) -> logging.Logger:
 113     assert config.has_been_parsed()
 114     if logger is None:
 115         logger = logging.getLogger()       # Root logger
 116
 117     if config.config['logging_config_file'] is not None:
 118         logging.config.fileConfig('logging.conf')
 119         return logger
 120
 121     handlers = []
 122     numeric_level = getattr(
 123         logging,
 124         config.config['logging_level'].upper(),
 125         None
 126     )
 127     if not isinstance(numeric_level, int):
 128         raise ValueError('Invalid level: %s' % config.config['logging_level'])
 129
 130     fmt = config.config['logging_format']
 131     if config.config['logging_debug_threads']:
 132         fmt = f'%(process)d.%(thread)d|{fmt}'
 133
 134     if config.config['logging_syslog']:
 135         if sys.platform in ('win32', 'cygwin'):
 136             print(
 137                 "WARNING: Current platform does not support syslog; IGNORING.",
 138                 file=sys.stderr
 139             )
 140         else:
 141             handler = SysLogHandler()
 142 #            for k, v in encoded_priorities.items():
 143 #                handler.encodePriority(k, v)
 144             handler.setFormatter(
 145                 MillisecondAwareFormatter(
 146                     fmt=fmt,
 147                     datefmt=config.config['logging_date_format'],
 148                 )
 149             )
 150             handler.setLevel(numeric_level)
 151             handlers.append(handler)
 152
 153     if config.config['logging_filename'] is not None:
 154         handler = RotatingFileHandler(
 155             config.config['logging_filename'],
 156             maxBytes = config.config['logging_filename_maxsize'],
 157             backupCount = config.config['logging_filename_count'],
 158         )
 159         handler.setLevel(numeric_level)
 160         handler.setFormatter(
 161             MillisecondAwareFormatter(
 162                 fmt=fmt,
 163                 datefmt=config.config['logging_date_format'],
 164             )
 165         )
 166         handlers.append(handler)
 167
 168     if config.config['logging_console']:
 169         handler = logging.StreamHandler(sys.stderr)
 170         handler.setLevel(numeric_level)
 171         handler.setFormatter(
 172             MillisecondAwareFormatter(
 173                 fmt=fmt,
 174                 datefmt=config.config['logging_date_format'],
 175             )
 176         )
 177         handlers.append(handler)
 178
 179     if len(handlers) == 0:
 180         handlers.append(logging.NullHandler())
 181
 182     for handler in handlers:
 183         logger.addHandler(handler)
 184     if config.config['logging_info_is_print']:
 185         handler = logging.StreamHandler(sys.stdout)
 186         handler.addFilter(OnlyInfoFilter())
 187         logger.addHandler(handler)
 188     logger.setLevel(numeric_level)
 189     logger.propagate = False
 190     return logger
 191
 192
 193 def get_logger(name: str = ""):
 194     logger = logging.getLogger(name)
 195     return initialize_logging(logger)
 196
 197
 198 def tprint(*args, **kwargs) -> None:
 199     if config.config['logging_debug_threads']:
 200         from thread_utils import current_thread_id
 201         print(f'{current_thread_id()}', end="")
 202         print(*args, **kwargs)
 203     else:
 204         pass
 205
 206
 207 def dprint(*args, **kwargs) -> None:
 208     print(*args, file=sys.stderr, **kwargs)
 209
 210
 211 class OutputSink(object):
 212
 213     # Bits in the destination_bitv bitvector.  Used to indicate the
 214     # output destination.
 215     STDOUT = 0x1
 216     STDERR = 0x2
 217     LOG_DEBUG = 0x4          # -\
 218     LOG_INFO = 0x8           #  |
 219     LOG_WARNING = 0x10       #   > Should provide logger to the c'tor.
 220     LOG_ERROR = 0x20         #  |
 221     LOG_CRITICAL = 0x40      # _/
 222     FILENAME = 0x80          # Must provide a filename to the c'tor.
 223     HLOG = 0x100
 224
 225     ALL_LOG_DESTINATIONS = (
 226         LOG_DEBUG | LOG_INFO | LOG_WARNING | LOG_ERROR | LOG_CRITICAL
 227     )
 228     ALL_OUTPUT_DESTINATIONS = 0x1FF
 229
 230     def __init__(self,
 231                  destination_bitv: int,
 232                  *,
 233                  logger=None,
 234                  filename=None):
 235         if logger is None:
 236             logger = logging.getLogger(None)
 237         self.logger = logger
 238
 239         if filename is not None:
 240             self.f = open(filename, "wb", buffering=0)
 241         else:
 242             if self.destination_bitv & OutputSink.FILENAME:
 243                 raise ValueError(
 244                     "Filename argument is required if bitv & FILENAME"
 245                 )
 246             self.f = None
 247         self.set_destination_bitv(destination_bitv)
 248
 249     def get_destination_bitv(self):
 250         return self.destination_bitv
 251
 252     def set_destination_bitv(self, destination_bitv: int):
 253         if destination_bitv & self.FILENAME and self.f is None:
 254             raise ValueError(
 255                 "Filename argument is required if bitv & FILENAME"
 256             )
 257         self.destination_bitv = destination_bitv
 258
 259     def print(self, *args, **kwargs):
 260         from string_utils import sprintf, strip_escape_sequences
 261         end = kwargs.pop("end", None)
 262         if end is not None:
 263             if not isinstance(end, str):
 264                 raise TypeError("end must be None or a string")
 265         sep = kwargs.pop("sep", None)
 266         if sep is not None:
 267             if not isinstance(sep, str):
 268                 raise TypeError("sep must be None or a string")
 269         if kwargs:
 270             raise TypeError("invalid keyword arguments to print()")
 271         buf = sprintf(*args, end="", sep=sep)
 272         if sep is None:
 273             sep = " "
 274         if end is None:
 275             end = "\n"
 276         if self.destination_bitv & self.STDOUT:
 277             print(buf, file=sys.stdout, sep=sep, end=end)
 278         if self.destination_bitv & self.STDERR:
 279             print(buf, file=sys.stderr, sep=sep, end=end)
 280         if end == '\n':
 281             buf += '\n'
 282         if self.destination_bitv & self.FILENAME and self.f is not None:
 283             self.f.write(buf.encode('utf-8'))
 284             self.f.flush()
 285         buf = strip_escape_sequences(buf)
 286         if self.logger is not None:
 287             if self.destination_bitv & self.LOG_DEBUG:
 288                 self.logger.debug(buf)
 289             if self.destination_bitv & self.LOG_INFO:
 290                 self.logger.info(buf)
 291             if self.destination_bitv & self.LOG_WARNING:
 292                 self.logger.warning(buf)
 293             if self.destination_bitv & self.LOG_ERROR:
 294                 self.logger.error(buf)
 295             if self.destination_bitv & self.LOG_CRITICAL:
 296                 self.logger.critical(buf)
 297         if self.destination_bitv & self.HLOG:
 298             hlog(buf)
 299
 300     def close(self):
 301         if self.f is not None:
 302             self.f.close()
 303
 304
 305 class OutputContext(OutputSink, contextlib.ContextDecorator):
 306     def __init__(self,
 307                  destination_bitv: int,
 308                  *,
 309                  logger=None,
 310                  filename=None):
 311         super().__init__(destination_bitv, logger=logger, filename=filename)
 312
 313     def __enter__(self):
 314         return self
 315
 316     def __exit__(self, etype, value, traceback):
 317         super().close()
 318         if etype is not None:
 319             return False
 320         return True
 321
 322
 323 def hlog(message: str) -> None:
 324     message = message.replace("'", "'\"'\"'")
 325     os.system(f"/usr/bin/logger -p local7.info -- '{message}'")