import functools
import itertools
import logging
import re
import threading
from collections import namedtuple
from inspect import isclass
from multiprocessing import current_process
from os import PathLike
from os.path import basename, normcase, splitext
from threading import current_thread
from colorama import AnsiToWin32
from . import _defaults
from ._datetime import now
from ._file_sink import FileSink
from ._get_frame import get_frame
from ._handler import Handler
from ._recattrs import ExceptionRecattr, FileRecattr, LevelRecattr, ProcessRecattr, ThreadRecattr
Level = namedtuple("Level", ["no", "color", "icon"])
start_time = now()
[docs]class Logger:
"""An object to dispatch logging messages to configured handlers.
The |Logger| is the core objet of `loguru`, every logging configuration and usage pass through
a call to one of its methods. There is only one logger, so there is no need to retrieve one
before usage.
Handlers to which send log messages are added using the |start| method. Note that you can
use the |Logger| right after import as it comes pre-configured. Messages can be logged with
different severity levels and using braces attributes like the |str.format| method do.
Once a message is logged, a "record" is associated with it. This record is a dict wich contains
several information about the logging context: time, function, file, line, thread, level...
It also contains the ``__name__`` of the module, this is why you don't need named loggers.
You should not instantiate a |Logger| by yourself, use ``from loguru import logger`` instead.
.. |Logger| replace:: :class:`~Logger`
.. |start| replace:: :meth:`~Logger.start()`
.. |stop| replace:: :meth:`~Logger.stop()`
.. |catch| replace:: :meth:`~Logger.catch()`
.. |bind| replace:: :meth:`~Logger.bind()`
.. |opt| replace:: :meth:`~Logger.opt()`
.. |log| replace:: :meth:`~Logger.log()`
.. |level| replace:: :meth:`~Logger.level()`
.. |enable| replace:: :meth:`~Logger.enable()`
.. |disable| replace:: :meth:`~Logger.disable()`
.. |str| replace:: :class:`str`
.. |int| replace:: :class:`int`
.. |bool| replace:: :class:`bool`
.. |tuple| replace:: :class:`tuple`
.. |list| replace:: :class:`list`
.. |dict| replace:: :class:`dict`
.. |str.format| replace:: :meth:`str.format()`
.. |Path| replace:: :class:`pathlib.Path`
.. |match.groupdict| replace:: :meth:`re.Match.groupdict()`
.. |Handler| replace:: :class:`logging.Handler`
.. |sys.stderr| replace:: :data:`sys.stderr`
.. |sys.exc_info| replace:: :func:`sys.exc_info()`
.. |time| replace:: :class:`datetime.time`
.. |datetime| replace:: :class:`datetime.datetime`
.. |timedelta| replace:: :class:`datetime.timedelta`
.. |open| replace:: :func:`open()`
.. |logging| replace:: :mod:`logging`
.. |Thread.run| replace:: :meth:`threading.Thread.run()`
.. |Exception| replace:: :class:`Exception`
.. |file-like object| replace:: ``file-like object``
.. _file-like object: https://docs.python.org/3/glossary.html#term-file-object
.. |class| replace:: ``class``
.. _class: https://docs.python.org/3/tutorial/classes.html
.. |function| replace:: ``function``
.. _function: https://docs.python.org/3/library/functions.html#callable
.. |re.Pattern| replace:: ``re.Pattern``
.. _re.Pattern: https://docs.python.org/3/library/re.html#re-objects
.. |re.Match| replace:: ``re.Match``
.. _re.Match: https://docs.python.org/3/library/re.html#match-objects
.. _Pendulum: https://pendulum.eustace.io/docs/#tokens
.. _ansimarkup: https://github.com/gvalkov/python-ansimarkup
.. _better_exceptions: https://github.com/Qix-/better-exceptions
.. _@sdispater: https://github.com/sdispater
.. _@gvalkov: https://github.com/gvalkov
.. _@Qix-: https://github.com/Qix-
"""
_levels = {
"TRACE": Level(
_defaults.LOGURU_TRACE_NO, _defaults.LOGURU_TRACE_COLOR, _defaults.LOGURU_TRACE_ICON
),
"DEBUG": Level(
_defaults.LOGURU_DEBUG_NO, _defaults.LOGURU_DEBUG_COLOR, _defaults.LOGURU_DEBUG_ICON
),
"INFO": Level(
_defaults.LOGURU_INFO_NO, _defaults.LOGURU_INFO_COLOR, _defaults.LOGURU_INFO_ICON
),
"SUCCESS": Level(
_defaults.LOGURU_SUCCESS_NO,
_defaults.LOGURU_SUCCESS_COLOR,
_defaults.LOGURU_SUCCESS_ICON,
),
"WARNING": Level(
_defaults.LOGURU_WARNING_NO,
_defaults.LOGURU_WARNING_COLOR,
_defaults.LOGURU_WARNING_ICON,
),
"ERROR": Level(
_defaults.LOGURU_ERROR_NO, _defaults.LOGURU_ERROR_COLOR, _defaults.LOGURU_ERROR_ICON
),
"CRITICAL": Level(
_defaults.LOGURU_CRITICAL_NO,
_defaults.LOGURU_CRITICAL_COLOR,
_defaults.LOGURU_CRITICAL_ICON,
),
}
_handlers_count = itertools.count()
_handlers = {}
_extra_class = {}
_min_level = float("inf")
_enabled = {}
_activation_list = []
_lock = threading.Lock()
def __init__(self, extra, exception, record, lazy, ansi, raw, depth):
self._extra = extra
self._record = record
self._exception = exception
self._lazy = lazy
self._ansi = ansi
self._raw = raw
self._depth = depth
[docs] def start(
self,
sink,
*,
level=_defaults.LOGURU_LEVEL,
format=_defaults.LOGURU_FORMAT,
filter=_defaults.LOGURU_FILTER,
colorize=_defaults.LOGURU_COLORIZE,
serialize=_defaults.LOGURU_SERIALIZE,
backtrace=_defaults.LOGURU_BACKTRACE,
enqueue=_defaults.LOGURU_ENQUEUE,
catch=_defaults.LOGURU_CATCH,
**kwargs
):
r"""Start sending log messages to a sink adequately configured.
Parameters
----------
sink : |file-like object|_, |str|, |Path|, |function|_, |Handler| or |class|_
An object in charge of receiving formatted logging messages and propagating them to an
appropriate endpoint.
level : |int| or |str|, optional
The minimum severity level from which logged messages should be send to the sink.
format : |str| or |function|_, optional
The template used to format logged messages before being sent to the sink.
filter : |function|_ or |str|, optional
A directive used to optionally filter out logged messages before they are send to the
sink.
colorize : |bool|, optional
Whether or not the color markups contained in the formatted message should be converted
to ansi codes for terminal coloration, ore stripped otherwise. If ``None``, the choice
is automatically made based on the sink being a tty or not.
serialize : |bool|, optional
Whether or not the logged message and its records should be first converted to a JSON
string before being sent to the sink.
backtrace : |bool|, optional
Whether or not the formatted exception should use stack trace to display local
variables values. This probably should be set to ``False`` in production to avoid
leaking sensitive data.
enqueue : |bool|, optional
Whether or not the messages to be logged should first pass through a multiprocess-safe
queue before reaching the sink. This is useful while logging to a file through multiple
processes.
catch : |bool|, optional
Whether or not errors occuring while sink handles logs messages should be caught or not.
If ``True``, an exception message is displayed on |sys.stderr| but the exception is not
propagated to the caller, preventing sink from stopping working.
**kwargs
Additional parameters that will be passed to the sink while creating it or while
logging messages (the exact behavior depends on the sink type).
If and only if the sink is a file, the following parameters apply:
Parameters
----------
rotation : |str|, |int|, |time|, |timedelta| or |function|_, optional
A condition indicating whenever the current logged file should be closed and a new one
started.
retention : |str|, |int|, |timedelta| or |function|_, optional
A directive filtering old files that should be removed during rotation or end of
program.
compression : |str| or |function|_, optional
A compression or archive format to which log files should be converted at closure.
delay : |bool|, optional
Whether or not the file should be created as soon as the sink is configured, or delayed
until first logged message. It defaults to ``False``.
mode : |str|, optional
The openning mode as for built-in |open| function. It defaults to ``"a"`` (open the
file in appending mode).
buffering : |int|, optional
The buffering policy as for built-in |open| function. It defaults to ``1`` (line
buffered file).
encoding : |str|, optional
The file encoding as for built-in |open| function. If ``None``, it defaults to
``locale.getpreferredencoding()``.
**kwargs
Others parameters are passed to the built-in |open| function.
Returns
-------
:class:`int`
An identifier associated with the starteds sink and which should be used to
|stop| it.
Notes
-----
Extended summary follows.
.. _sink:
.. rubric:: The sink parameter
The ``sink`` handles incomming log messages and proceed to their writing somewhere and
somehow. A sink can take many forms:
- A |file-like object|_ like ``sys.stderr`` or ``open("somefile.log", "w")``. Anything with
a ``.write()`` method is considered as a file-like object. If it has a ``.flush()``
method, it will be automatically called after each logged message. If it has a ``.stop()``
method, it will be automatically called at sink termination.
- A file path as |str| or |Path|. It can be parametrized with some additional parameters,
see bellow.
- A simple |function|_ like ``lambda msg: print(msg)``. This allows for logging
procedure entirely defined by user preferences and needs.
- A built-in |Handler| like ``logging.StreamHandler``. In such a case, the `Loguru` records
are automatically converted to the structure expected by the |logging| module.
- A |class|_ object that will be used to instantiate the sink using ``**kwargs`` attributes
passed. Hence the class should instantiate objects which are therefore valid sinks.
.. _message:
.. rubric:: The logged message
The logged message passed to all started sinks is nothing more than a string of the
formatted log, to which a special attribute is associated: the ``.record`` which is a dict
containing all contextual information possibly needed (see bellow).
Logged messages are formatted according to the ``format`` of the started sink. This format
is usually a string containing braces fields to display attributes from the record dict.
If fine-grained control is needed, the ``format`` can also be a function which takes the
record as parameter and return the format template string. However, note that in such a
case, you should take care of appending the line ending and exception field to the returned
format, while ``"\n{exception}"`` is automatically appended for convenience if ``format`` is
a string.
The ``filter`` attribute can be used to control which messages are effectively passed to the
sink and which one are ignored. A function can be used, accepting the record as an
argument, and returning ``True`` if the message should be logged, ``False`` otherwise. If
a string is used, only the records with the same ``name`` and its children will be allowed.
.. _record:
.. rubric:: The record dict
The record is just a Python dict, accessible from sinks by ``message.record``, and usable
for formatting as ``"{key}"``. Some record's values are objects with two or more attibutes,
those can be formatted with ``"{key.attr}"`` (``"{key}"`` would display one by default).
Formatting directives like ``"{key: >3}"`` also works and is specially useful for time (see
bellow).
+------------+---------------------------------+----------------------------+
| Key | Description | Attributes |
+============+=================================+============================+
| elapsed | The time elapsed since the | See |timedelta| |
| | start of the program | |
+------------+---------------------------------+----------------------------+
| exception | The formatted exception if any, | ``type``, ``value``, |
| | ``None`` otherwise | ``traceback`` |
+------------+---------------------------------+----------------------------+
| extra | The dict of attributes | None |
| | bound by the user | |
+------------+---------------------------------+----------------------------+
| file | The file where the logging call | ``name`` (default), |
| | was made | ``path`` |
+------------+---------------------------------+----------------------------+
| function | The function from which the | None |
| | logging call was made | |
+------------+---------------------------------+----------------------------+
| level | The severity used to log the | ``name`` (default), |
| | the message | ``no``, ``icon`` |
+------------+---------------------------------+----------------------------+
| line | The line number in the source | None |
| | code | |
+------------+---------------------------------+----------------------------+
| message | The logged message (not yet | None |
| | formatted) | |
+------------+---------------------------------+----------------------------+
| module | The module where the logging | None |
| | call was made | |
+------------+---------------------------------+----------------------------+
| name | The ``__name__`` where the | None |
| | logging call was made | |
+------------+---------------------------------+----------------------------+
| process | The process in which the | ``name``, ``id`` (default) |
| | logging call was made | |
+------------+---------------------------------+----------------------------+
| thread | The thread in which the | ``name``, ``id`` (default) |
| | logging call was made | |
+------------+---------------------------------+----------------------------+
| time | The local time when the logging | See |datetime| |
| | call was made | |
+------------+---------------------------------+----------------------------+
.. _time:
.. rubric:: The time formatting
The time field can be formatted using more human-friendly tokens. Those constitute a subset
of the one used by the `Pendulum`_ library by `@sdispater`_. To escape a token, just add
square brackets around it.
+------------------------+---------+----------------------------------------+
| | Token | Output |
+========================+=========+========================================+
| Year | YYYY | 2000, 2001, 2002 ... 2012, 2013 |
| +---------+----------------------------------------+
| | YY | 00, 01, 02 ... 12, 13 |
+------------------------+---------+----------------------------------------+
| Quarter | Q | 1 2 3 4 |
+------------------------+---------+----------------------------------------+
| Month | MMMM | January, February, March ... |
| +---------+----------------------------------------+
| | MMM | Jan, Feb, Mar ... |
| +---------+----------------------------------------+
| | MM | 01, 02, 03 ... 11, 12 |
| +---------+----------------------------------------+
| | M | 1, 2, 3 ... 11, 12 |
+------------------------+---------+----------------------------------------+
| Day of Year | DDDD | 001, 002, 003 ... 364, 365 |
| +---------+----------------------------------------+
| | DDD | 1, 2, 3 ... 364, 365 |
+------------------------+---------+----------------------------------------+
| Day of Month | DD | 01, 02, 03 ... 30, 31 |
| +---------+----------------------------------------+
| | D | 1, 2, 3 ... 30, 31 |
+------------------------+---------+----------------------------------------+
| Day of Week | dddd | Monday, Tuesday, Wednesday ... |
| +---------+----------------------------------------+
| | ddd | Mon, Tue, Wed ... |
| +---------+----------------------------------------+
| | d | 0, 1, 2 ... 6 |
+------------------------+---------+----------------------------------------+
| Days of ISO Week | E | 1, 2, 3 ... 7 |
+------------------------+---------+----------------------------------------+
| Hour | HH | 00, 01, 02 ... 23, 24 |
| +---------+----------------------------------------+
| | H | 0, 1, 2 ... 23, 24 |
| +---------+----------------------------------------+
| | hh | 01, 02, 03 ... 11, 12 |
| +---------+----------------------------------------+
| | h | 1, 2, 3 ... 11, 12 |
+------------------------+---------+----------------------------------------+
| Minute | mm | 00, 01, 02 ... 58, 59 |
| +---------+----------------------------------------+
| | m | 0, 1, 2 ... 58, 59 |
+------------------------+---------+----------------------------------------+
| Second | ss | 00, 01, 02 ... 58, 59 |
| +---------+----------------------------------------+
| | s | 0, 1, 2 ... 58, 59 |
+------------------------+---------+----------------------------------------+
| Fractional Second | S | 0 1 ... 8 9 |
| +---------+----------------------------------------+
| | SS | 00, 01, 02 ... 98, 99 |
| +---------+----------------------------------------+
| | SSS | 000 001 ... 998 999 |
| +---------+----------------------------------------+
| | SSSS... | 000[0..] 001[0..] ... 998[0..] 999[0..]|
| +---------+----------------------------------------+
| | SSSSSS | 000000 000001 ... 999998 999999 |
+------------------------+---------+----------------------------------------+
| AM / PM | A | AM, PM |
+------------------------+---------+----------------------------------------+
| Timezone | Z | -07:00, -06:00 ... +06:00, +07:00 |
| +---------+----------------------------------------+
| | ZZ | -0700, -0600 ... +0600, +0700 |
| +---------+----------------------------------------+
| | zz | EST CST ... MST PST |
+------------------------+---------+----------------------------------------+
| Seconds timestamp | X | 1381685817, 1234567890.123 |
+------------------------+---------+----------------------------------------+
| Microseconds timestamp | x | 1234567890123 |
+------------------------+---------+----------------------------------------+
.. _file:
.. rubric:: The file sinks
If the sink is a |str| or a |Path|, the corresponding file will be opened for writing logs.
The path can also contains a special ``"{time}"`` field that will be formatted with the
current date at file creation.
The ``rotation`` check is made before logging each messages. If there is already an existing
file with the same name that the file to be created, then the existing file is renamed by
appending the date to its basename to prevent file overwritting. This parameter accepts:
- an |int| which corresponds to the maximum file size in bytes before that the current
logged file is closed and a new one started over.
- a |timedelta| which indicates the frequency of each new rotation.
- a |time| which specifies the hour when the daily rotation should occur.
- a |str| for human-friendly parametrization of one of the previously enumerated types.
Examples: ``"100 MB"``, ``"0.5 GB"``, ``"1 month 2 weeks"``, ``"4 days"``, ``"10h"``,
``"monthly"``, ``"18:00"``, ``"sunday"``, ``"w0"``, ``"monday at 12:00"``, ...
- a |function|_ which will be called before logging. It should accept two
arguments: the logged message and the file object, and it should return ``True`` if
the rotation should happen now, ``False`` otherwise.
The ``retention`` occurs at rotation or at sink stop if rotation is ``None``. Files are
selected according to their basename, if it is the same that the sink file, with possible
time field being replaced with ``.*``. This parameter accepts:
- an |int| which indicates the number of log files to keep, while older files are removed.
- a |timedelta| which specifies the maximum age of files to keep.
- a |str| for human-friendly parametrization of the maximum age of files to keep.
Examples: ``"1 week, 3 days"``, ``"2 months"``, ...
- a |function|_ which will be called before the retention process. It should accept the list
of log files as argument and process to whatever it wants (moving files, removing them,
etc.).
The ``compression`` happens at rotation or at sink stop if rotation is ``None``. This
parameter acccepts:
- a |str| which corresponds to the compressed or archived file extension. This can be one
of: ``"gz"``, ``"bz2"``, ``"xz"``, ``"lzma"``, ``"tar"``, ``"tar.gz"``, ``"tar.bz2"``,
``"tar.xz"``, ``"zip"``.
- a |function|_ which will be called before file termination. It should accept the path
of the log file as argument and process to whatever it wants (custom compression,
network sending, removing it, etc.).
.. _color:
.. rubric:: The color markups
To add colors to your logs, you just have to enclose your format string with the appropriate
tags. This is based on the great `ansimarkup`_ library from `@gvalkov`_. Those tags are
removed if the sink don't support ansi codes.
The special tag ``<level>`` (abbreviated with ``<lvl>``) is transformed according to
the configured color of the logged message level.
Here are the available tags (note that compatibility may vary depending on terminal):
+------------------------------------+--------------------------------------+
| Color (abbr) | Styles (abbr) |
+====================================+======================================+
| Black (k) | Bold (b) |
+------------------------------------+--------------------------------------+
| Blue (e) | Dim (d) |
+------------------------------------+--------------------------------------+
| Cyan (c) | Normal (n) |
+------------------------------------+--------------------------------------+
| Green (g) | Italic (i) |
+------------------------------------+--------------------------------------+
| Magenta (m) | Underline (u) |
+------------------------------------+--------------------------------------+
| Red (r) | Strike (s) |
+------------------------------------+--------------------------------------+
| White (w) | Reverse (r) |
+------------------------------------+--------------------------------------+
| Yellow (y) | Blink (l) |
+------------------------------------+--------------------------------------+
| | Hide (h) |
+------------------------------------+--------------------------------------+
Usage:
+-----------------+-------------------------------------------------------------------+
| Description | Examples |
| +---------------------------------+---------------------------------+
| | Foreground | Background |
+=================+=================================+=================================+
| Basic colors | ``<red>``, ``<r>`` | ``<GREEN>``, ``<G>`` |
+-----------------+---------------------------------+---------------------------------+
| Light colors | ``<light-blue>``, ``<le>`` | ``<LIGHT-CYAN>``, ``<LC>`` |
+-----------------+---------------------------------+---------------------------------+
| Xterm colors | ``<fg 86>``, ``<fg 255>`` | ``<bg 42>``, ``<bg 9>`` |
+-----------------+---------------------------------+---------------------------------+
| Hex colors | ``<fg #00005f>``, ``<fg #EE1>`` | ``<bg #AF5FD7>``, ``<bg #fff>`` |
+-----------------+---------------------------------+---------------------------------+
| RGB colors | ``<fg 0,95,0>`` | ``<bg 72,119,65>`` |
+-----------------+---------------------------------+---------------------------------+
| Stylizing | ``<bold>``, ``<b>`` , ``<underline>``, ``<u>`` |
+-----------------+-------------------------------------------------------------------+
| Shorthand | ``<red, yellow>``, ``<r, y>`` |
| (FG, BG) | |
+-----------------+-------------------------------------------------------------------+
| Shorthand | ``<bold, cyan, white>``, ``<b,,w>``, ``<b,c,>`` |
| (Style, FG, BG) | |
+-----------------+-------------------------------------------------------------------+
.. _env:
.. rubric:: The environment variables
The default values of sink parameters can be entirely customized. This is particularly
useful if you don't like the log format of the pre-configured sink.
Each of the |start| default parameter can be modified by setting the ``LOGURU_[PARAM]``
environment variable. For example on Linux: ``export LOGURU_FORMAT="{time} - {message}"``
or ``export LOGURU_ENHANCE=NO``.
The default levels attributes can also be modified by setting the ``LOGURU_[LEVEL]_[ATTR]``
environment variable. For example, on Windows: ``setx LOGURU_DEBUG_COLOR="<blue>"``
or ``setx LOGURU_TRACE_ICON="๐"``.
If you want to disable the pre-configured sink, you can set the ``LOGURU_AUTOINIT``
variable to ``False``.
Examples
--------
>>> logger.start(sys.stdout, format="{time} - {level} - {message}", filter="sub.module")
>>> logger.start("file_{time}.log", level="TRACE", rotation="100 MB")
>>> def my_sink(message):
... record = message.record
... update_db(message, time=record.time, level=record.level)
...
>>> logger.start(my_sink)
>>> from logging import StreamHandler
>>> logger.start(StreamHandler(sys.stderr), format="{message}")
>>> class RandomStream:
... def __init__(self, seed, threshold):
... self.threshold = threshold
... random.seed(seed)
... def write(self, message):
... if random.random() > self.threshold:
... print(message)
...
>>> stream_object = RandomStream(seed=12345, threhold=0.25)
>>> logger.start(stream_object, level="INFO")
>>> logger.start(RandomStream, level="DEBUG", seed=34567, threshold=0.5)
"""
if colorize is None and serialize:
colorize = False
if isclass(sink):
sink = sink(**kwargs)
return self.start(
sink,
level=level,
format=format,
filter=filter,
colorize=colorize,
serialize=serialize,
backtrace=backtrace,
enqueue=enqueue,
catch=catch,
)
elif isinstance(sink, (str, PathLike)):
path = sink
sink = FileSink(path, **kwargs)
return self.start(
sink,
level=level,
format=format,
filter=filter,
colorize=colorize,
serialize=serialize,
backtrace=backtrace,
enqueue=enqueue,
catch=catch,
)
elif hasattr(sink, "write") and callable(sink.write):
if colorize is False:
stream = sink
else:
try:
converter = AnsiToWin32(sink, convert=None, strip=False)
isatty = converter.stream.isatty()
except Exception:
if colorize is None:
colorize = False
stream = sink
else:
if colorize is None:
colorize = isatty
if converter.should_wrap() and colorize:
stream = converter.stream
else:
stream = sink
stream_write = stream.write
if kwargs:
def write(m):
return stream_write(m, **kwargs)
else:
write = stream_write
if hasattr(stream, "flush") and callable(stream.flush):
stream_flush = stream.flush
def writer(m):
write(m)
stream_flush()
else:
writer = write
if hasattr(stream, "stop") and callable(stream.stop):
stopper = stream.stop
else:
def stopper():
return None
elif isinstance(sink, logging.Handler):
def writer(m):
r = m.record
exc = r["exception"]
record = logging.root.makeRecord(
r["name"],
r["level"].no,
r["file"].path,
r["line"],
r["message"],
(),
(exc.type, exc.value, exc.traceback) if exc else None,
r["function"],
r["extra"],
**kwargs
)
sink.handle(record)
stopper = sink.close
if colorize is None:
colorize = False
elif callable(sink):
if kwargs:
def writer(m):
return sink(m, **kwargs)
else:
writer = sink
def stopper():
return None
if colorize is None:
colorize = False
else:
raise ValueError("Cannot log to objects of type '%s'." % type(sink).__name__)
if filter is None or filter == "":
filter_func = None
elif isinstance(filter, str):
parent = filter + "."
length = len(parent)
def filter_func(r):
return (r["name"] + ".")[:length] == parent
elif callable(filter):
filter_func = filter
else:
raise ValueError(
"Invalid filter, it should be a function or a string, not: '%s'"
% type(filter).__name__
)
if isinstance(level, str):
levelno = self.level(level).no
elif isinstance(level, int):
levelno = level
else:
raise ValueError(
"Invalid level, it should be an integer or a string, not: '%s'"
% type(level).__name__
)
if levelno < 0:
raise ValueError(
"Invalid level value, it should be a positive integer, not: %d" % levelno
)
if isinstance(format, str):
formatter = format + "\n{exception}"
is_formatter_dynamic = False
elif callable(format):
formatter = format
is_formatter_dynamic = True
else:
raise ValueError(
"Invalid format, it should be a string or a function, not: '%s'"
% type(format).__name__
)
try:
encoding = sink.encoding
except AttributeError:
encoding = "ascii"
with self._lock:
colors = [lvl.color for lvl in self._levels.values()] + [""]
handler = Handler(
writer=writer,
stopper=stopper,
levelno=levelno,
formatter=formatter,
is_formatter_dynamic=is_formatter_dynamic,
filter_=filter_func,
colorize=colorize,
serialize=serialize,
backtrace=backtrace,
catch=catch,
enqueue=enqueue,
encoding=encoding,
colors=colors,
)
handler_id = next(self._handlers_count)
self._handlers[handler_id] = handler
self.__class__._min_level = min(self.__class__._min_level, levelno)
return handler_id
[docs] def stop(self, handler_id=None):
"""Stop logging to a previously started sink.
Parameters
----------
handler_id : |int| or ``None``
The id of the sink to stop, as it was returned by the |start| method. If ``None``,
all sinks are stopped. The pre-configured sink is guaranteed to have the index ``0``.
Examples
--------
>>> i = logger.start(sys.stderr, format="{message}")
>>> logger.info("Logging")
Logging
>>> logger.stop(i)
>>> logger.info("No longer logging")
"""
with self._lock:
if handler_id is None:
for handler in self._handlers.values():
handler.stop()
self._handlers.clear()
else:
try:
handler = self._handlers.pop(handler_id)
except KeyError:
raise ValueError("There is no started handler with id '%s'" % handler_id)
handler.stop()
levelnos = (h.levelno for h in self._handlers.values())
self.__class__._min_level = min(levelnos, default=float("inf"))
[docs] def catch(
self,
exception=Exception,
*,
level="ERROR",
reraise=False,
message="An error has been caught in function '{record[function]}', "
"process '{record[process].name}' ({record[process].id}), "
"thread '{record[thread].name}' ({record[thread].id}):"
):
"""Return a decorator to automatically log possibly caught error in wrapped function.
This is useful to ensure unexpected exceptions are logged, the entire program can be
wrapped by this method. This is also very useful to decorate |Thread.run| methods while
using threads to propagate errors to the main logger thread.
Note that the visibility of variables values (which uses the cool `better_exceptions`_
library from `@Qix-`_) depends on the ``backtrace`` option of each configured sinks.
The returned object can also be used as a context manager.
Parameters
----------
exception : |Exception|, optional
The type of exception to intercept. If several types should be caught, a tuple of
exceptions can be used too.
level : |str| or |int|, optional
The level name or severity with which the message should be logged.
reraise : |bool|, optional
Whether or not the exception should be raised again and hence propagated to the caller.
message : |str|, optional
The message that will be automatically logged if an exception occurs. Note that it will
be formatted with the ``record`` attribute.
Returns
-------
decorator / context manager
An object that can be used to decorate a function or as a context manager to log
exceptions possibly caught.
Examples
--------
>>> @logger.catch
... def f(x):
... 100 / x
...
>>> def g():
... f(10)
... f(0)
...
>>> g()
ERROR - An error has been caught in function 'g', process 'Main' (367), thread 'ch1' (1398):
Traceback (most recent call last, catch point marked):
File "program.py", line 12, in <module>
g()
โ <function g at 0x7f225fe2bc80>
> File "program.py", line 10, in g
f(0)
โ <function f at 0x7f225fe2b9d8>
File "program.py", line 6, in f
100 / x
โ 0
ZeroDivisionError: division by zero
>>> with logger.catch(message="Because we never know..."):
... main() # No exception, no logs
...
"""
if callable(exception) and (
not isclass(exception) or not issubclass(exception, BaseException)
):
return self.catch()(exception)
class Catcher:
def __init__(self, as_decorator):
self._as_decorator = as_decorator
def __enter__(self_):
return None
def __exit__(self_, type_, value, traceback_):
if type_ is None:
return
if not issubclass(type_, exception):
return False
if self_._as_decorator:
back, decorator = 2, True
else:
back, decorator = 1, False
logger_ = self.opt(
exception=True,
record=True,
lazy=self._lazy,
ansi=self._ansi,
raw=self._raw,
depth=self._depth + back,
)
log = logger_._make_log_function(level, decorator)
log(logger_, message)
return not reraise
def __call__(self_, function):
catcher = Catcher(True)
@functools.wraps(function)
def catch_wrapper(*args, **kwargs):
with catcher:
return function(*args, **kwargs)
return catch_wrapper
return Catcher(False)
[docs] def opt(self, *, exception=None, record=False, lazy=False, ansi=False, raw=False, depth=0):
r"""Parametrize a logging call to slightly change generated log message.
Parameters
----------
exception : |bool|, |tuple| or |Exception|, optional
It if does not evaluate as ``False``, the passed exception is formatted and added to the
log message. It could be an |Exception| object or a ``(type, value, traceback)`` tuple,
otherwise the exception information is retrieved from |sys.exc_info|.
record : |bool|, optional
If ``True``, the record dict contextualizing the logging call can be used to format the
message by using ``{record[key]}`` in the log message.
lazy : |bool|, optional
If ``True``, the logging call attribute to format the message should be functions which
will be called only if the level is high enough. This can be used to avoid expensive
functions if not necessary.
ansi : |bool|, optional
If ``True``, logged message will be colorized according to the markups it possibly
contains.
raw : |bool|, optional
If ``True``, the formatting of each sink will be bypassed and the message will be send
as is.
depth : |int|, optional
Specify which stacktrace should be used to contextualize the logged message. This is
useful while using the logger from inside a wrapped function to retrieve worthwhile
information.
Returns
-------
:class:`~Logger`
A logger wrapping the core logger, but transforming logged message adequately before
sending.
Examples
--------
>>> try:
... 1 / 0
... except ZeroDivisionError:
... logger.opt(exception=True).debug("Exception logged with debug level:")
...
[18:10:02] DEBUG in '<module>' - Exception logged with debug level:
Traceback (most recent call last, catch point marked):
> File "<stdin>", line 2, in <module>
ZeroDivisionError: division by zero
>>> logger.opt(record=True).info("Current line is: {record[line]}")
[18:10:33] INFO in '<module>' - Current line is: 1
>>> logger.opt(lazy=True).debug("If sink <= DEBUG: {x}", x=lambda: math.factorial(2**5))
[18:11:19] DEBUG in '<module>' - If sink <= DEBUG: 263130836933693530167218012160000000
>>> logger.opt(ansi=True).warning("We got a <red>BIG</red> problem")
[18:11:30] WARNING in '<module>' - We got a BIG problem
>>> logger.opt(raw=True).debug("No formatting\n")
No formatting
>>> def wrapped():
... logger.opt(depth=1).info("Get parent context")
...
>>> def func():
... wrapped()
...
>>> func()
[18:11:54] DEBUG in 'func' - Get parent context
"""
return Logger(self._extra, exception, record, lazy, ansi, raw, depth)
[docs] def bind(_self, **kwargs):
"""Bind attributes to the ``extra`` dict of each logged message record.
This is used to add custom context to each logging call.
Parameters
----------
**kwargs
Mapping between keys and values that will be added to the ``extra`` dict.
Returns
-------
:class:`~Logger`
A logger wrapping the core logger, but which sends record with the customized ``extra``
dict.
Examples
--------
>>> logger.start(sys.stderr, format="{extra[ip]} - {message}")
1
>>> class Server:
... def __init__(self, ip):
... self.ip = ip
... self.logger = logger.bind(ip=ip)
... def call(self, message):
... self.logger.info(message)
...
>>> instance_1 = Server("192.168.0.200")
>>> instance_2 = Server("127.0.0.1")
>>> instance_1.call("First instance")
192.168.0.200 - First instance
>>> instance_2.call("Second instance")
127.0.0.1 - Second instance
"""
return Logger(
{**_self._extra, **kwargs},
_self._exception,
_self._record,
_self._lazy,
_self._ansi,
_self._raw,
_self._depth,
)
[docs] def level(self, name, no=None, color=None, icon=None):
"""Add, update or retrieve a logging level.
Logging levels are defined by their ``name`` to which a severity ``no``, an ansi ``color``
and an ``icon`` are associated and possibly modified at run-time. To |log| to a custom
level, you should necessarily use its name, the severity number is not linked back to levels
name (this implies that several levels can share the same severity).
To add a new level, all parameters should be passed so it can be properly configured.
To update an existing level, pass its ``name`` with the parameters to be changed.
To retrieve level information, the ``name`` solely suffices.
Parameters
----------
name : |str|
The name of the logging level.
no : |int|
The severity of the level to be added or updated.
color : |str|
The color markup of the level to be added or updated.
icon : |str|
The icon of the level to be added or updated.
Returns
-------
``Level``
A namedtuple containing information about the level.
Examples
--------
>>> level = logger.level("ERROR")
Level(no=40, color='<red><bold>', icon='โ')
>>> logger.start(sys.stderr, format="{level.no} {icon} {message}")
>>> logger.level("CUSTOM", no=15, color="<blue>", icon="@")
>>> logger.log("CUSTOM", "Logging...")
15 @ Logging...
>>> logger.level("WARNING", icon=r"/!\\")
>>> logger.warning("Updated!")
30 /!\\ Updated!
"""
if not isinstance(name, str):
raise ValueError(
"Invalid level name, it should be a string, not: '%s'" % type(name).__name__
)
if no is color is icon is None:
try:
return self._levels[name]
except KeyError:
raise ValueError("Level '%s' does not exist" % name)
if name not in self._levels:
if no is None:
raise ValueError(
"Level '%s' does not exist, you have to create it by specifying a level no"
% name
)
else:
old_no, old_color, old_icon = None, "", " "
else:
old_no, old_color, old_icon = self.level(name)
if no is None:
no = old_no
if color is None:
color = old_color
if icon is None:
icon = old_icon
if not isinstance(no, int):
raise ValueError(
"Invalid level no, it should be an integer, not: '%s'" % type(no).__name__
)
if no < 0:
raise ValueError("Invalid level no, it should be a positive integer, not: %d" % no)
self._levels[name] = Level(no, color, icon)
with self._lock:
for handler in self._handlers.values():
handler.update_format(color)
return self.level(name)
[docs] def disable(self, name):
"""Disable logging of messages comming from ``name`` module and its children.
Developers of library using `Loguru` should absolutely disable it to avoid disrupting
users with unrelated logs messages.
Parameters
----------
name : |str|
The name of the parent module to disable.
Examples
--------
>>> logger.info("Allowed message by default")
[22:21:55] Allowed message by default
>>> logger.disable("my_library")
>>> logger.info("While publishing a library, don't forget to disable logging")
"""
self._change_activation(name, False)
[docs] def enable(self, name):
"""Enable logging of messages comming from ``name`` module and its children.
Logging is generally disabled by imported library using `Loguru`, hence this function
allows users to receive these messages anyway.
Parameters
----------
name : |str|
The name of the parent module to re-allow.
Examples
--------
>>> logger.disable("__main__")
>>> logger.info("Disabled, so nothing is logged.")
>>> logger.enable("__main__")
>>> logger.info("Re-enabled, messages are logged.")
[22:46:12] Re-enabled, messages are logged.
"""
self._change_activation(name, True)
def _change_activation(self, name, status):
if not isinstance(name, str):
raise ValueError("Invalid name, it should be a string, not: '%s'" % type(name).__name__)
if name != "":
name += "."
with self._lock:
activation_list = [(n, s) for n, s in self._activation_list if n[: len(name)] != name]
parent_status = next((s for n, s in activation_list if name[: len(n)] == n), None)
if parent_status != status and not (name == "" and status == True):
activation_list.append((name, status))
def key_sort(x):
return x[0].count(".")
activation_list.sort(key=key_sort, reverse=True)
with self._lock:
for n in self._enabled:
if (n + ".")[: len(name)] == name:
self._enabled[n] = status
self._activation_list[:] = activation_list
[docs] @staticmethod
def parse(file, pattern, *, cast={}, chunk=2 ** 16):
"""
Parse raw logs and extract each entry as a |dict|.
The logging format has to be specified as the regex ``pattern``, it will then be
used to parse the ``file`` and retrieve each entries based on the named groups present
in the regex.
Parameters
----------
file : |str|, |Path| or |file-like object|_
The path of the log file to be parsed, or alternatively an already opened file object.
pattern : |str| or |re.Pattern|_
The regex to use for logs parsing, it should contain named groups which will be included
in the returned dict.
cast : |function|_ or |dict|, optional
A function that should convert in-place the regex groups parsed (a dict of string
values) to more appropiate types. If a dict is passed, its should be a mapping between
keys of parsed log dict and the function that should be used to convert the associated
value.
chunk : |int|, optional
The number of bytes read while iterating through the logs, this avoid having to load the
whole file in memory.
Yields
------
:class:`dict`
The dict mapping regex named groups to matched values, as returned by |match.groupdict|
and optionally converted according to ``cast`` argument.
Examples
--------
>>> reg = r"(?P<lvl>[0-9]+): (?P<msg>.*)" # If log format is "{level.no} - {message}"
>>> for e in logger.parse("file.log", reg): # A file line could be "10 - A debug message"
... print(e) # => {'lvl': '10', 'msg': 'A debug message'}
...
>>> caster = dict(lvl=int) # Parse 'lvl' key as an integer
>>> for e in logger.parse("file.log", reg, cast=caster):
... print(e) # => {'lvl': 10, 'msg': 'A debug message'}
>>> def cast(groups):
... if "date" in groups:
... groups["date"] = datetime.strptime(groups["date"], "%Y-%m-%d %H:%M:%S")
...
>>> with open("file.log") as file:
... for log in logger.parse(file, reg, cast=cast):
... print(log["date"], log["something_else"])
"""
if isinstance(file, (str, PathLike)):
should_close = True
fileobj = open(str(file))
elif hasattr(file, "read") and callable(file.read):
should_close = False
fileobj = file
else:
raise ValueError(
"Invalid file, it should be a string path or a file object, not: '%s'"
% type(file).__name__
)
if isinstance(cast, dict):
def cast_function(groups):
for key, converter in cast.items():
if key in groups:
groups[key] = converter(groups[key])
elif callable(cast):
cast_function = cast
else:
raise ValueError(
"Invalid cast, it should be a function or a dict, not: '%s'" % type(cast).__name__
)
try:
regex = re.compile(pattern)
except TypeError:
raise ValueError(
"Invalid pattern, it should be a string or a compiled regex, not: '%s'"
% type(pattern).__name__
)
matches = Logger._find_iter(fileobj, regex, chunk)
for match in matches:
groups = match.groupdict()
cast_function(groups)
yield groups
if should_close:
fileobj.close()
@staticmethod
def _find_iter(fileobj, regex, chunk):
buffer = fileobj.read(0)
while 1:
text = fileobj.read(chunk)
buffer += text
matches = list(regex.finditer(buffer))
if not text:
yield from matches
break
if len(matches) > 1:
end = matches[-2].end()
buffer = buffer[end:]
yield from matches[:-1]
@staticmethod
@functools.lru_cache()
def _make_log_function(level, decorated=False):
if isinstance(level, str):
level_id = level_name = level
elif isinstance(level, int):
if level < 0:
raise ValueError(
"Invalid level value, it should be a positive integer, not: %d" % level
)
level_id = None
level_name = "Level %d" % level
else:
raise ValueError(
"Invalid level, it should be an integer or a string, not: '%s'"
% type(level).__name__
)
def log_function(_self, _message, *args, **kwargs):
if not _self._handlers:
return
frame = get_frame(_self._depth + 1)
name = frame.f_globals["__name__"]
try:
if not _self._enabled[name]:
return
except KeyError:
dotted_name = name + "."
for dotted_module_name, status in _self._activation_list:
if dotted_name[: len(dotted_module_name)] == dotted_module_name:
if status:
break
_self._enabled[name] = False
return
_self._enabled[name] = True
current_datetime = now()
if level_id is None:
level_no, level_color, level_icon = level, "", " "
else:
try:
level_no, level_color, level_icon = _self._levels[level_name]
except KeyError:
raise ValueError("Level '%s' does not exist" % level_name)
if level_no < _self._min_level:
return
code = frame.f_code
file_path = normcase(code.co_filename)
file_name = basename(file_path)
thread = current_thread()
process = current_process()
elapsed = current_datetime - start_time
level_recattr = LevelRecattr(level_name)
level_recattr.no, level_recattr.name, level_recattr.icon = (
level_no,
level_name,
level_icon,
)
file_recattr = FileRecattr(file_name)
file_recattr.name, file_recattr.path = file_name, file_path
thread_ident = thread.ident
thread_recattr = ThreadRecattr(thread_ident)
thread_recattr.id, thread_recattr.name = thread_ident, thread.name
process_ident = process.ident
process_recattr = ProcessRecattr(process_ident)
process_recattr.id, process_recattr.name = process_ident, process.name
if _self._exception:
exception = ExceptionRecattr(_self._exception, decorated)
else:
exception = None
record = {
"elapsed": elapsed,
"exception": exception,
"extra": {**_self._extra_class, **_self._extra},
"file": file_recattr,
"function": code.co_name,
"level": level_recattr,
"line": frame.f_lineno,
"message": _message,
"module": splitext(file_name)[0],
"name": name,
"process": process_recattr,
"thread": thread_recattr,
"time": current_datetime,
}
if _self._lazy:
args = [arg() for arg in args]
kwargs = {key: value() for key, value in kwargs.items()}
if _self._record:
record["message"] = _message.format(*args, **kwargs, record=record)
elif args or kwargs:
record["message"] = _message.format(*args, **kwargs)
for handler in _self._handlers.values():
handler.emit(record, level_color, _self._ansi, _self._raw)
doc = r"Log ``_message.format(*args, **kwargs)`` with severity ``'%s'``." % level_name
log_function.__doc__ = doc
return log_function
trace = _make_log_function.__func__("TRACE")
debug = _make_log_function.__func__("DEBUG")
info = _make_log_function.__func__("INFO")
success = _make_log_function.__func__("SUCCESS")
warning = _make_log_function.__func__("WARNING")
error = _make_log_function.__func__("ERROR")
critical = _make_log_function.__func__("CRITICAL")
[docs] def log(_self, _level, _message, *args, **kwargs):
r"""Log ``_message.format(*args, **kwargs)`` with severity ``_level``."""
logger = _self.opt(
exception=_self._exception,
record=_self._record,
lazy=_self._lazy,
ansi=_self._ansi,
raw=_self._raw,
depth=_self._depth + 1,
)
logger._make_log_function(_level)(logger, _message, *args, **kwargs)
[docs] def exception(_self, _message, *args, **kwargs):
r"""Convenience method for logging an ``'ERROR'`` with exception information."""
logger = _self.opt(
exception=True,
record=_self._record,
lazy=_self._lazy,
ansi=_self._ansi,
raw=_self._raw,
depth=_self._depth + 1,
)
logger._make_log_function("ERROR")(logger, _message, *args, **kwargs)