Coverage for cronlog.py: 21%

1# 

2# Copyright 2013, Martin Owens <doctormo@gmail.com> 

3# 

4# This library is free software; you can redistribute it and/or 

5# modify it under the terms of the GNU Lesser General Public 

6# License as published by the Free Software Foundation; either 

7# version 3.0 of the License, or (at your option) any later version. 

8# 

9# This library is distributed in the hope that it will be useful, 

10# but WITHOUT ANY WARRANTY; without even the implied warranty of 

11# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 

12# Lesser General Public License for more details. 

13# 

14# You should have received a copy of the GNU Lesser General Public 

15# License along with this library. 

16# 

17""" 

18Access logs in known locations to find information about them. 

19""" 

20 

21import os (empty)

22import re (empty)

23import codecs (empty)

24import platform (empty)

25from dateutil import parser as dateparse (empty)

26 

27MATCHER = r'(?P<date>\w+ +\d+ +\d\d:\d\d:\d\d) (?P<host>\w+) ' + \ (empty)

28 r'CRON\[(?P<pid>\d+)\]: \((?P<user>\w+)\) CMD \((?P<cmd>.*)\)' 

29 

30class LogReader(object): (empty)

31 """Opens a Log file, reading backwards and watching for changes""" 

32 def __init__(self, filename, mass=4096): (empty)

33 self.filename = filename 

34 self.mass = mass 

35 self.size = -1 

36 self.read = -1 

37 self.pipe = None 

38 

39 def __enter__(self): (empty)

40 self.size = os.stat(self.filename)[6] 

41 self.pipe = codecs.open(self.filename, 'r', encoding='utf-8') 

42 return self 

43 

44 def __exit__(self, error_type, value, traceback): (empty)

45 self.pipe.close() 

46 

47 def __iter__(self): (empty)

48 if self.pipe is None: 

49 with self as reader: 

50 for (offset, line) in reader.readlines(): 

51 yield line 

52 else: 

53 for (offset, line) in self.readlines(): 

54 yield line 

55 

56 def readlines(self, until=0): (empty)

57 """Iterator for reading lines from a file backwards""" 

58 if not self.pipe or self.pipe.closed: 

59 raise IOError("Can't readline, no opened file.") 

60 # Always seek to the end of the file, this accounts for file updates 

61 # that happen during our running process. 

62 location = self.size 

63 halfline = '' 

64 

65 while location > until: 

66 location -= self.mass 

67 mass = self.mass 

68 if location < 0: 

69 mass = self.mass + location 

70 location = 0 

71 self.pipe.seek(location) 

72 line = self.pipe.read(mass) + halfline 

73 data = line.split('\n') 

74 if location != 0: 

75 halfline = data.pop(0) 

76 loc = location + mass 

77 data.reverse() 

78 for line in data: 

79 if line.strip() == '': 

80 continue 

81 yield (loc, line) 

82 loc -= len(line) 

83 

84 

85 

86class CronLog(LogReader): (empty)

87 """Use the LogReader to make a Cron specific log reader""" 

88 def __init__(self, filename='/var/log/syslog', user=None): (empty)

89 LogReader.__init__(self, filename) 

90 self.user = user 

91 

92 def for_program(self, command): (empty)

93 """Return log entries for this specific command name""" 

94 return ProgramLog(self, command) 

95 

96 def __iter__(self): (empty)

97 for line in super(CronLog, self).__iter__(): 

98 match = re.match(MATCHER, str(line)) 

99 datum = match and match.groupdict() 

100 if datum and (not self.user or datum['user'] == self.user): 

101 datum['date'] = dateparse.parse(datum['date']) 

102 yield datum 

103 

104 

105class ProgramLog(object): (empty)

106 """Specific log control for a single command/program""" 

107 def __init__(self, log, command): (empty)

108 self.log = log 

109 self.command = command 

110 

111 def __iter__(self): (empty)

112 for entry in self.log: 

113 if entry['cmd'] == str(self.command): 

114 yield entry 

115