logging_utils.py

   1 #!/usr/bin/env python3
   2
   3 """Utilities related to logging."""
   4
   5 import contextlib
   6 import logging
   7 from logging.handlers import RotatingFileHandler, SysLogHandler
   8 import os
   9 import sys
  10
  11 import argparse_utils
  12 import config
  13 import string_utils as su
  14 import thread_utils as tu
  15
  16 parser = config.add_commandline_args(
  17     f'Logging ({__file__})',
  18     'Args related to logging')
  19 parser.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 parser.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 parser.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 parser.add_argument(
  41     '--logging_date_format',
  42     type=str,
  43     default='%Y/%m/%dT%H:%M:%S%z',
  44     metavar='DATEFMT',
  45     help='The format of any dates in --logging_format.'
  46 )
  47 parser.add_argument(
  48     '--logging_console',
  49     action=argparse_utils.ActionNoYes,
  50     default=True,
  51     help='Should we log to the console (stderr)',
  52 )
  53 parser.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 parser.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 parser.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 parser.add_argument(
  75     '--logging_syslog',
  76     action=argparse_utils.ActionNoYes,
  77     default=False,
  78     help='Should we log to localhost\'s syslog.'
  79 )
  80 parser.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 parser.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 def initialize_logging(logger=None) -> logging.Logger:
 100     assert config.has_been_parsed()
 101     if logger is None:
 102         logger = logging.getLogger()       # Root logger
 103
 104     if config.config['logging_config_file'] is not None:
 105         logging.config.fileConfig('logging.conf')
 106         return logger
 107
 108     handlers = []
 109     numeric_level = getattr(
 110         logging,
 111         config.config['logging_level'].upper(),
 112         None
 113     )
 114     if not isinstance(numeric_level, int):
 115         raise ValueError('Invalid level: %s' % config.config['logging_level'])
 116
 117     fmt = config.config['logging_format']
 118     if config.config['logging_debug_threads']:
 119         fmt = f'%(process)d.%(thread)d|{fmt}'
 120
 121     if config.config['logging_syslog']:
 122         if sys.platform in ('win32', 'cygwin'):
 123             print(
 124                 "WARNING: Current platform does not support syslog; IGNORING.",
 125                 file=sys.stderr
 126             )
 127         else:
 128             handler = SysLogHandler()
 129 #            for k, v in encoded_priorities.items():
 130 #                handler.encodePriority(k, v)
 131             handler.setFormatter(
 132                 logging.Formatter(
 133                     fmt=fmt,
 134                     datefmt=config.config['logging_date_format'],
 135                 )
 136             )
 137             handler.setLevel(numeric_level)
 138             handlers.append(handler)
 139
 140     if config.config['logging_filename'] is not None:
 141         handler = RotatingFileHandler(
 142             config.config['logging_filename'],
 143             maxBytes = config.config['logging_filename_maxsize'],
 144             backupCount = config.config['logging_filename_count'],
 145         )
 146         handler.setLevel(numeric_level)
 147         handler.setFormatter(
 148             logging.Formatter(
 149                 fmt=fmt,
 150                 datefmt=config.config['logging_date_format'],
 151             )
 152         )
 153         handlers.append(handler)
 154
 155     if config.config['logging_console']:
 156         handler = logging.StreamHandler(sys.stderr)
 157         handler.setLevel(numeric_level)
 158         handler.setFormatter(
 159             logging.Formatter(
 160                 fmt=fmt,
 161                 datefmt=config.config['logging_date_format'],
 162             )
 163         )
 164         handlers.append(handler)
 165
 166     if len(handlers) == 0:
 167         handlers.append(logging.NullHandler())
 168
 169     for handler in handlers:
 170         logger.addHandler(handler)
 171     if config.config['logging_info_is_print']:
 172         handler = logging.StreamHandler(sys.stdout)
 173         handler.addFilter(OnlyInfoFilter())
 174         logger.addHandler(handler)
 175     logger.setLevel(numeric_level)
 176     logger.propagate = False
 177     return logger
 178
 179
 180 def get_logger(name: str = ""):
 181     logger = logging.getLogger(name)
 182     return initialize_logging(logger)
 183
 184
 185 def tprint(*args, **kwargs) -> None:
 186     if config.config['logging_debug_threads']:
 187         print(f'{tu.current_thread_id()}', end="")
 188         print(*args, **kwargs)
 189     else:
 190         pass
 191
 192
 193 def dprint(*args, **kwargs) -> None:
 194     print(*args, file=sys.stderr, **kwargs)
 195
 196
 197 class OutputSink(object):
 198
 199     # Bits in the destination_bitv bitvector.  Used to indicate the
 200     # output destination.
 201     STDOUT = 0x1
 202     STDERR = 0x2
 203     LOG_DEBUG = 0x4          # -\
 204     LOG_INFO = 0x8           #  |
 205     LOG_WARNING = 0x10       #   > Should provide logger to the c'tor.
 206     LOG_ERROR = 0x20         #  |
 207     LOG_CRITICAL = 0x40      # _/
 208     FILENAME = 0x80          # Must provide a filename to the c'tor.
 209     HLOG = 0x100
 210
 211     ALL_LOG_DESTINATIONS = (
 212         LOG_DEBUG | LOG_INFO | LOG_WARNING | LOG_ERROR | LOG_CRITICAL
 213     )
 214     ALL_OUTPUT_DESTINATIONS = 0x1FF
 215
 216     def __init__(self,
 217                  destination_bitv: int,
 218                  *,
 219                  logger=None,
 220                  filename=None):
 221         if logger is None:
 222             logger = logging.getLogger(None)
 223         self.logger = logger
 224
 225         if filename is not None:
 226             self.f = open(filename, "wb", buffering=0)
 227         else:
 228             if self.destination_bitv & OutputSink.FILENAME:
 229                 raise ValueError(
 230                     "Filename argument is required if bitv & FILENAME"
 231                 )
 232             self.f = None
 233         self.set_destination_bitv(destination_bitv)
 234
 235     def get_destination_bitv(self):
 236         return self.destination_bitv
 237
 238     def set_destination_bitv(self, destination_bitv: int):
 239         if destination_bitv & self.FILENAME and self.f is None:
 240             raise ValueError(
 241                 "Filename argument is required if bitv & FILENAME"
 242             )
 243         self.destination_bitv = destination_bitv
 244
 245     def print(self, *args, **kwargs):
 246         end = kwargs.pop("end", None)
 247         if end is not None:
 248             if not isinstance(end, str):
 249                 raise TypeError("end must be None or a string")
 250         sep = kwargs.pop("sep", None)
 251         if sep is not None:
 252             if not isinstance(sep, str):
 253                 raise TypeError("sep must be None or a string")
 254         if kwargs:
 255             raise TypeError("invalid keyword arguments to print()")
 256         buf = su.sprintf(*args, end="", sep=sep)
 257         if sep is None:
 258             sep = " "
 259         if end is None:
 260             end = "\n"
 261         if self.destination_bitv & self.STDOUT:
 262             print(buf, file=sys.stdout, sep=sep, end=end)
 263         if self.destination_bitv & self.STDERR:
 264             print(buf, file=sys.stderr, sep=sep, end=end)
 265         if end == '\n':
 266             buf += '\n'
 267         if self.destination_bitv & self.FILENAME and self.f is not None:
 268             self.f.write(buf.encode('utf-8'))
 269             self.f.flush()
 270         buf = su.strip_escape_sequences(buf)
 271         if self.logger is not None:
 272             if self.destination_bitv & self.LOG_DEBUG:
 273                 self.logger.debug(buf)
 274             if self.destination_bitv & self.LOG_INFO:
 275                 self.logger.info(buf)
 276             if self.destination_bitv & self.LOG_WARNING:
 277                 self.logger.warning(buf)
 278             if self.destination_bitv & self.LOG_ERROR:
 279                 self.logger.error(buf)
 280             if self.destination_bitv & self.LOG_CRITICAL:
 281                 self.logger.critical(buf)
 282         if self.destination_bitv & self.HLOG:
 283             hlog(buf)
 284
 285     def close(self):
 286         if self.f is not None:
 287             self.f.close()
 288
 289
 290 class OutputContext(OutputSink, contextlib.ContextDecorator):
 291     def __init__(self,
 292                  destination_bitv: int,
 293                  *,
 294                  logger=None,
 295                  filename=None):
 296         super().__init__(destination_bitv, logger=logger, filename=filename)
 297
 298     def __enter__(self):
 299         return self
 300
 301     def __exit__(self, etype, value, traceback):
 302         super().close()
 303         if etype is not None:
 304             return False
 305         return True
 306
 307
 308 def hlog(message: str) -> None:
 309     message = message.replace("'", "'\"'\"'")
 310     os.system(f"/usr/bin/logger -p local7.info -- '{message}'")