lo99ing 0.1.4

Logger Behavior

Default behavior when using lo99ing:

• logs to stderr only

• log level (of each individual logger) defaults to:

• WARNING for “installed” modules (site-packages and dist-packages)

• INFO for “local” modules (in user’s local dev env)

• message format: %(asctime)s:%(levelname)s:%(name)s: %(message)s

Message Logging Behavior

• logger.exception() automatically extracts and prints exception attributes

• When logging an exception object, automatically adds exception type:

• logger.error('exception raised: %s', KeyError(0)) # prints: 'exception raised: KeyError -- 0'

• if logging messages fails formatting, also logs the location of the problematic call:

• logger.info('forgot the percent sign', 555) # includes: 'Logged from /path/to/file.py:LINENUM'

Usage and Other Features

• Get a logger using get_logger(logger_name, ...)

• Get a logger with current module’s (or script’s) basename using: get_logger(__file__)

• Log to a file, using enable_file(filename)

• Create an “independent” (i.e., propagate=False) file-logger, using get_file_logger(filename)

• Disable/re-enable logging to stderr (on root logger), using enable_stderr() and disable_stderr()

• Change logging clock “converter” to UTC using use_utc()

• Change logging clock to a custom clock using use_clock(clock)

• This is useful when “replaying past events”, and you want timestamps to appear accordingly

• log-level overrides: set and reset (“undo”) log levels using overrides:

• logger.set_log_level_override(level) or set_log_level_override(name, level),

• reset using set_log_level_override(name, None)

• Create a logger-like object, which adds a prefix to messages it logs, using logger.prefixed('PREFIX:')

• Log a “trace” message with current filename and line number, using logger.TRACE()

• useful for “tracing” / “printf-debugging”

Usage Notes

• Should avoid using logging.getLogger() directly. Instead, use lo99ing.get_logger()

• Should not use logger.setLevel() directly. Instead, use get_logger(..., level=LEVEL, ...) or set_log_level_override()

Installation

Using pip:

pip install lo99ing