Source code for snapshotlog

# Back In Time
# Copyright (C) 2016-2017 Germar Reitze
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License along
# with this program; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

import os
import re
import gettext

import logger
import snapshots
import tools

_=gettext.gettext


[docs]class LogFilter(object): """ A Filter for snapshot logs which will both decode log lines and filter them for the requested ``mode``. Args: mode (int): which filter should be used. Possible values: :py:data:`NO_FILTER`, :py:data:`ERROR`, :py:data:`CHANGES`, :py:data:`INFORMATION` or :py:data:`ERROR_AND_CHANGES` decode (encfstools.Decode): instance used for decoding lines or ``None`` """ NO_FILTER = 0 ERROR = 1 CHANGES = 2 INFORMATION = 3 ERROR_AND_CHANGES = 4 REGEX = {None: None, NO_FILTER: None, ERROR: re.compile(r'^(?:\[E\]|[^\[])'), CHANGES: re.compile(r'^(?:\[C\]|[^\[])'), INFORMATION: re.compile(r'^(?:\[I\]|[^\[])'), ERROR_AND_CHANGES: re.compile(r'^(?:\[E\]|\[C\]|[^\[])')} def __init__(self, mode = 0, decode = None): self.regex = self.REGEX[mode] self.decode = decode if decode: self.header = _('### This log has been decoded with automatic search pattern\n'\ '### If some paths are not decoded you can manually decode them with:\n') self.header += '### \'backintime --quiet ' if int(decode.config.currentProfile()) > 1: self.header += '--profile "%s" ' %decode.config.profileName() self.header += '--decode <path>\'\n\n' else: self.header = ''
[docs] def filter(self, line): """ Filter and decode ``line`` with predefined ``mode`` and ``decode`` instance. Args: line (str): log line read from disk Returns: str: decoded ``line`` or ``None`` if the line was filtered """ if not line: #keep empty lines return line if self.regex and not self.regex.match(line): return if self.decode: return self.decode.log(line) else: return line
[docs]class SnapshotLog(object): """ Read and write Snapshot log to "~/.local/share/backintime/takesnapshot_<N>.log". Where <N> is the profile ID ``profile``. Args: cfg (config.Config): current config profile (int): profile that should be used to indentify the log """ NONE = 0 ERRORS = 1 CHANGES_AND_ERRORS = 2 ALL = 3 def __init__(self, cfg, profile = None): self.config = cfg if profile: self.profile = profile else: self.profile = cfg.currentProfile() self.logLevel = cfg.logLevel() self.logFileName = cfg.takeSnapshotLogFile(self.profile) self.logFile = None self.timer = tools.Alarm(self.flush, overwrite = False) def __del__(self): if self.logFile: self.logFile.close()
[docs] def get(self, mode = None, decode = None, skipLines = 0): """ Read the log, filter and decode it and yield its lines. Args: mode (int): Mode used for filtering. Take a look at :py:class:`snapshotlog.LogFilter` decode (encfstools.Decode): instance used for decoding lines or ``None`` skipLines (int): skip ``n`` lines before yielding lines. This is used to append only new lines to LogView Yields: str: filtered and decoded log lines """ logFilter = LogFilter(mode, decode) count = logFilter.header.count('\n') try: with open(self.logFileName, 'rt') as f: if logFilter.header and not skipLines: yield logFilter.header for line in f.readlines(): line = logFilter.filter(line.rstrip('\n')) if not line is None: count += 1 if count <= skipLines: continue yield line except Exception as e: msg = ('Failed to get take_snapshot log from {}:'.format(self.logFile), str(e)) logger.debug(' '.join(msg), self) for line in msg: yield line
[docs] def new(self, date): """ Create a new log file or - if the last new_snapshot can be continued - add a note to the current log. Args: date (datetime.datetime): current date """ if snapshots.NewSnapshot(self.config).saveToContinue: msg = "Last snapshot didn't finish but can be continued.\n\n" msg += "======== continue snapshot (profile %s): %s ========\n" else: if os.path.exists(self.logFileName): if self.logFile: self.logFile.close() self.logFile = None os.remove(self.logFileName) msg = "========== Take snapshot (profile %s): %s ==========\n" self.append(msg %(self.profile, date.strftime('%c')), 1)
[docs] def append(self, msg, level): """ Append ``msg`` to the log if ``level`` is lower than configured log level. Args: msg (str): message line that should be added to the log level (int): verbosity level of current line. msg will only be added to log if level is lower than configured log level :py:func:`config.Config.logLevel`. Posible Values: :py:data:`SnapshotLog.ERRORS`, :py:data:`SnapshotLog.CHANGES_AND_ERRORS` or :py:data:`SnapshotLog.ALL` """ if level > self.logLevel: return if not self.logFile: self.logFile = open(self.logFileName, 'at') self.logFile.write(msg + '\n') self.timer.start(5)
[docs] def flush(self): """ Force write log to file. """ if self.logFile: self.logFile.flush()