import logging
import os
import sys
try:
import curses
except ImportError:
curses = None
def _stderr_supports_color():
color = False
if curses and hasattr(sys.stderr, 'isatty') and sys.stderr.isatty():
try:
curses.setupterm()
if curses.tigetnum("colors") > 0:
color = True
except Exception:
pass
return color
class LogFormatter(logging.Formatter):
"""Log formatter originally from Tornado and modified."""
DEFAULT_FORMAT = '%(color)s[%(levelname)1.1s %(asctime)s %(process)d]%(end_color)s %(message)s'
DEFAULT_DATE_FORMAT = '%y%m%d %H:%M:%S'
DEFAULT_COLORS = {
logging.DEBUG: 4, # Blue
logging.INFO: 2, # Green
logging.WARNING: 3, # Yellow
logging.ERROR: 1, # Red
}
def __init__(self, color=True, fmt=DEFAULT_FORMAT, datefmt=DEFAULT_DATE_FORMAT,
colors=DEFAULT_COLORS, precision=3):
r"""
:arg bool color: Enables color support.
:arg string fmt: Log message format.
It will be applied to the attributes dict of log records. The
text between ``%(color)s`` and ``%(end_color)s`` will be colored
depending on the level if color support is on.
:arg dict colors: color mappings from logging level to terminal color
code
:arg string datefmt: Datetime format.
Used for formatting ``(asctime)`` placeholder in ``prefix_fmt``.
.. versionchanged:: 3.2
Added ``fmt`` and ``datefmt`` arguments.
"""
super().__init__()
self.default_time_format = datefmt
self.precision = precision
self.default_msec_format = ''
self._fmt = fmt
self._colors = {}
if color and _stderr_supports_color():
fg_color = (curses.tigetstr('setaf') or
curses.tigetstr('setf') or '')
for levelno, code in colors.items():
self._colors[levelno] = curses.tparm(fg_color, code).decode()
self._normal = curses.tigetstr('sgr0').decode()
else:
self._normal = ''
def format(self, record):
record.message = record.getMessage()
record.asctime = self.formatTime(record)
if record.levelno in self._colors:
record.color = self._colors[record.levelno]
record.end_color = self._normal
else:
record.color = record.end_color = ''
formatted = self._fmt % record.__dict__
if record.exc_info:
if not record.exc_text:
record.exc_text = self.formatException(record.exc_info)
if record.exc_text:
lines = [formatted.rstrip()]
lines.extend(ln for ln in record.exc_text.split('\n'))
formatted = '\n'.join(lines)
return formatted.replace('\n', '\n ')
def formatTime(self, record, datefmt=None):
if not datefmt:
datefmt = self.default_time_format
fmttime = super().formatTime(record, datefmt)
if self.precision >= 4:
return '%s.%06d' % (fmttime, record.msecs*1000)
if self.precision >= 1:
return '%s.%03d' % (fmttime, record.msecs)
return fmttime
def setup_logger(name=None, level=None, formatter_opts=None):
"""Sets up pretty logging using LogFormatter."""
if formatter_opts is None:
formatter_opts = {}
logging.captureWarnings(True)
logger = logging.getLogger(name)
if 'DEBUG' in os.environ:
level = logging.DEBUG
elif level is None:
level = logging.INFO
logger.setLevel(level)
channel = logging.StreamHandler()
formatter = LogFormatter(**formatter_opts)
channel.setFormatter(formatter)
logger.addHandler(channel)
return logger
