X-Git-Url: https://wannabe.guru.org/gitweb/?a=blobdiff_plain;f=logging_utils.py;h=de69046c30a82914b04e288982fcf93455fcb965;hb=d2478310649d51e14f8ece57651ca9d925d98793;hp=eec07984b282b9a0ef1e4adea7ab6951a0abc71e;hpb=eb9e6df32ed696158bf34dba6464277b648f5c74;p=python_utils.git diff --git a/logging_utils.py b/logging_utils.py index eec0798..de69046 100644 --- a/logging_utils.py +++ b/logging_utils.py @@ -10,12 +10,12 @@ import io import logging from logging.handlers import RotatingFileHandler, SysLogHandler import os -import pytz import random import sys from typing import Callable, Iterable, Mapping, Optional from overrides import overrides +import pytz # This module is commonly used by others in here and should avoid # taking any unnecessary dependencies back on them. @@ -43,8 +43,8 @@ cfg.add_argument( cfg.add_argument( '--logging_format', type=str, - default='%(levelname).1s:%(asctime)s: %(message)s', - help='The format for lines logged via the logger module.' + default=None, + help='The format for lines logged via the logger module. See: https://docs.python.org/3/library/logging.html#formatter-objects' ) cfg.add_argument( '--logging_date_format', @@ -76,7 +76,7 @@ cfg.add_argument( cfg.add_argument( '--logging_filename_count', type=int, - default=2, + default=7, metavar='COUNT', help='The number of logging_filename copies to keep before deleting.' ) @@ -86,12 +86,28 @@ cfg.add_argument( default=False, help='Should we log to localhost\'s syslog.' ) +cfg.add_argument( + '--logging_syslog_facility', + type=str, + default = 'USER', + choices=['NOTSET', 'AUTH', 'AUTH_PRIV', 'CRON', 'DAEMON', 'FTP', 'KERN', 'LPR', 'MAIL', 'NEWS', + 'SYSLOG', 'USER', 'UUCP', 'LOCAL0', 'LOCAL1', 'LOCAL2', 'LOCAL3', 'LOCAL4', 'LOCAL5', + 'LOCAL6', 'LOCAL7'], + metavar='SYSLOG_FACILITY_LIST', + help='The default syslog message facility identifier', +) cfg.add_argument( '--logging_debug_threads', action=argparse_utils.ActionNoYes, default=False, help='Should we prepend pid/tid data to all log messages?' ) +cfg.add_argument( + '--logging_debug_modules', + action=argparse_utils.ActionNoYes, + default=False, + help='Should we prepend module/function data to all log messages?' +) cfg.add_argument( '--logging_info_is_print', action=argparse_utils.ActionNoYes, @@ -99,13 +115,13 @@ cfg.add_argument( help='logging.info also prints to stdout.' ) cfg.add_argument( - '--logging_squelch_repeats_enabled', + '--logging_squelch_repeats', action=argparse_utils.ActionNoYes, default=True, help='Do we allow code to indicate that it wants to squelch repeated logging messages or should we always log?' ) cfg.add_argument( - '--logging_probabilistically_enabled', + '--logging_probabilistically', action=argparse_utils.ActionNoYes, default=True, help='Do we allow probabilistic logging (for code that wants it) or should we always log?' @@ -127,9 +143,20 @@ cfg.add_argument( 'module:function, or :function and is a logging level (e.g. INFO, DEBUG...)' ) ) - +cfg.add_argument( + '--logging_clear_preexisting_handlers', + action=argparse_utils.ActionNoYes, + default=False, + help=( + 'Should logging code clear preexisting global logging handlers and thus insist that is ' + + 'alone can add handlers. Use this to work around annoying modules that insert global ' + + 'handlers with formats and logging levels you might now want. Caveat emptor, this may ' + + 'cause you to miss logging messages.' + ) +) built_in_print = print +logging_initialized = False def function_identifier(f: Callable) -> str: @@ -187,7 +214,11 @@ class SquelchRepeatedMessagesFilter(logging.Filter): This filter only affects logging messages that repeat more than a threshold number of times from functions that are tagged with - the @logging_utils.squelched_logging_ok decorator. + the @logging_utils.squelched_logging_ok decorator; others are + ignored. + + This functionality is enabled by default but can be disabled via + the --no_logging_squelch_repeats commandline flag. """ def __init__(self) -> None: @@ -207,8 +238,8 @@ class SquelchRepeatedMessagesFilter(logging.Filter): class DynamicPerScopeLoggingLevelFilter(logging.Filter): - """Only interested in seeing logging messages from an allow list of - module names or module:function names. Block others. + """This filter only allows logging messages from an allow list of + module names or module:function names. Blocks others. """ @staticmethod @@ -295,6 +326,10 @@ def logging_is_probabilistic(probability_of_logging: float) -> Callable: (i.e. they do not always unconditionally log) but rather are probabilistic (i.e. they log N% of the time randomly). + Note that this functionality can be disabled (forcing all logged + messages to produce output) via the --no_logging_probabilistically + cmdline argument. + This affects *ALL* logging statements within the marked function. """ @@ -338,7 +373,8 @@ class OnlyInfoFilter(logging.Filter): class MillisecondAwareFormatter(logging.Formatter): """ - A formatter for adding milliseconds to log messages. + A formatter for adding milliseconds to log messages which, for + whatever reason, the default python logger doesn't do. """ converter = datetime.datetime.fromtimestamp @@ -357,9 +393,20 @@ class MillisecondAwareFormatter(logging.Formatter): def initialize_logging(logger=None) -> logging.Logger: - assert config.has_been_parsed() + global logging_initialized + if logging_initialized: + return + logging_initialized = True + if logger is None: - logger = logging.getLogger() # Root logger + logger = logging.getLogger() + + preexisting_handlers_count = 0 + assert config.has_been_parsed() + if config.config['logging_clear_preexisting_handlers']: + while logger.hasHandlers(): + logger.removeHandler(logger.handlers[0]) + preexisting_handlers_count += 1 if config.config['logging_config_file'] is not None: logging.config.fileConfig('logging.conf') @@ -376,13 +423,24 @@ def initialize_logging(logger=None) -> logging.Logger: if not isinstance(default_logging_level, int): raise ValueError('Invalid level: %s' % config.config['logging_level']) - fmt = config.config['logging_format'] + if config.config['logging_format']: + fmt = config.config['logging_format'] + else: + if config.config['logging_syslog']: + fmt = '%(levelname).1s:%(filename)s[%(process)d]: %(message)s' + else: + fmt = '%(levelname).1s:%(asctime)s: %(message)s' if config.config['logging_debug_threads']: fmt = f'%(process)d.%(thread)d|{fmt}' + if config.config['logging_debug_modules']: + fmt = f'%(filename)s:%(funcName)s:%(lineno)s|{fmt}' if config.config['logging_syslog']: if sys.platform not in ('win32', 'cygwin'): - handler = SysLogHandler() + if config.config['logging_syslog_facility']: + facility_name = 'LOG_' + config.config['logging_syslog_facility'] + facility = SysLogHandler.__dict__.get(facility_name, SysLogHandler.LOG_USER) + handler = SysLogHandler(facility=facility, address='/dev/log') handler.setFormatter( MillisecondAwareFormatter( fmt=fmt, @@ -426,11 +484,11 @@ def initialize_logging(logger=None) -> logging.Logger: handler.addFilter(OnlyInfoFilter()) logger.addHandler(handler) - if config.config['logging_squelch_repeats_enabled']: + if config.config['logging_squelch_repeats']: for handler in handlers: handler.addFilter(SquelchRepeatedMessagesFilter()) - if config.config['logging_probabilistically_enabled']: + if config.config['logging_probabilistically']: for handler in handlers: handler.addFilter(ProbabilisticFilter()) @@ -457,6 +515,56 @@ def initialize_logging(logger=None) -> logging.Logger: built_in_print(*arg, **kwarg) builtins.print = print_and_also_log + # At this point the logger is ready, handlers are set up, + # etc... so log about the logging configuration. + + level_name = logging._levelToName.get(default_logging_level, str(default_logging_level)) + logger.debug( + f'Initialized global logging; default logging level is {level_name}.' + ) + if config.config['logging_clear_preexisting_handlers'] and preexisting_handlers_count > 0: + logger.warning( + 'Logging cleared {preexisting_handlers_count} global handlers (--logging_clear_preexisting_handlers)' + ) + logger.debug(f'Logging format specification is "{fmt}"') + if config.config['logging_debug_threads']: + logger.debug('...Logging format spec captures tid/pid (--logging_debug_threads)') + if config.config['logging_debug_modules']: + logger.debug('...Logging format spec captures files/functions/lineno (--logging_debug_modules)') + if config.config['logging_syslog']: + logger.debug(f'Logging to syslog as {facility_name} with priority mapping based on level') + if config.config['logging_filename']: + logger.debug(f'Logging to filename {config.config["logging_filename"]}') + logger.debug(f'...with {config.config["logging_filename_maxsize"]} bytes max file size.') + logger.debug(f'...and {config.config["logging_filename_count"]} rotating backup file count.') + if config.config['logging_console']: + logger.debug('Logging to the console (stderr).') + if config.config['logging_info_is_print']: + logger.debug( + 'Logging logger.info messages will be repeated on stdout (--logging_info_is_print)' + ) + if config.config['logging_squelch_repeats']: + logger.debug( + 'Logging code allowed to request repeated messages be squelched (--logging_squelch_repeats)' + ) + else: + logger.debug( + 'Logging code forbidden to request messages be squelched; all messages logged (--no_logging_squelch_repeats)' + ) + if config.config['logging_probabilistically']: + logger.debug( + 'Logging code is allowed to request probabilistic logging (--logging_probabilistically)' + ) + else: + logger.debug( + 'Logging code is forbidden to request probabilistic logging; messages always logged (--no_logging_probabilistically)' + ) + if config.config['lmodule']: + logger.debug( + 'Logging dynamic per-module logging enabled (--lmodule={config.config["lmodule"]})' + ) + if config.config['logging_captures_prints']: + logger.debug('Logging will capture printed data as logger.info messages (--logging_captures_prints)') return logger @@ -466,8 +574,11 @@ def get_logger(name: str = ""): def tprint(*args, **kwargs) -> None: - """Legacy function for printing a message augmented with thread id.""" + """Legacy function for printing a message augmented with thread id + still needed by some code. Please use --logging_debug_threads in + new code. + """ if config.config['logging_debug_threads']: from thread_utils import current_thread_id print(f'{current_thread_id()}', end="") @@ -477,8 +588,11 @@ def tprint(*args, **kwargs) -> None: def dprint(*args, **kwargs) -> None: - """Legacy function used to print to stderr.""" + """Legacy function used to print to stderr still needed by some code. + Please just use normal logging with --logging_console which + accomplishes the same thing in new code. + """ print(*args, file=sys.stderr, **kwargs) @@ -486,7 +600,8 @@ class OutputMultiplexer(object): """ A class that broadcasts printed messages to several sinks (including various logging levels, different files, different file handles, - the house log, etc...) + the house log, etc...). See also OutputMultiplexerContext for an + easy usage pattern. """ class Destination(enum.IntEnum): @@ -645,8 +760,13 @@ class OutputMultiplexerContext(OutputMultiplexer, contextlib.ContextDecorator): def hlog(message: str) -> None: - """Write a message to the house log.""" + """Write a message to the house log (syslog facility local7 priority + info) by calling /usr/bin/logger. This is pretty hacky but used + by a bunch of code. Another way to do this would be to use + --logging_syslog and --logging_syslog_facility but I can't + actually say that's easier. + """ message = message.replace("'", "'\"'\"'") os.system(f"/usr/bin/logger -p local7.info -- '{message}'")