介紹 Python Logging Framework 的元件、設定與使用 - logger, handler - level, filter, format - config (dict, file) - logging flow

1. Python Logging

2. Me?
•
== Chen Chun-Chia
== CCC
• MitraCloud
>>> Python/Django
>>> Android
2

3. • logger, handler
• level, filter, formatter
• config
• logging flow

4. Python 3.4
4

5. >>> import logging
>>> logging.warning('haha')
WARNING:root:haha
5

6. >>> import logging
>>> logging.warning('haha')
WARNING:root:haha
Log level
6

7. >>> import logging
>>> logging.warning('haha')
WARNING:root:haha
Log message
7

8. >>> import logging
>>> logging.warning('haha')
WARNING:root:haha
Log level
8

9. >>> import logging
>>> logging.warning('haha')
WARNING:root:haha
Log message
9

10. >>> import logging
>>> logging.warning('haha')
WARNING:root:haha
... logger
10

11. >>> import logging
>>> logging.warning('haha')
WARNING:root:haha
IN
OUT
11

12. Logging
12

13. Logger Handler
13

14. Logger Handler
level
filter
level
filter
formatter
14

15. Handler
Logger Handler
level
filter
level
filter
formatter
config
Logger
15

16. level
16

17. >>> import logging
>>> logging.warning('haha')
WARNING:root:haha
Log level
17

18. level
level
———————
CRITICAL
ERROR
WARNING
INFO
DEBUG
50
40
30
20
10
18

19. level
logging.basicConfig(level=logging.ERROR)
logging.critical('critical')
logging.error('error')
logging.warning('warning')
logging.info('info')
logging.debug('debug')
CRITICAL:root:critical
ERROR:root:error
level
———————
CRITICAL
ERROR
WARNING
INFO
DEBUG
19

20. level
logging.basicConfig(level=logging.INFO)
logging.critical('critical')
logging.error('error')
logging.warning('warning')
logging.info('info')
logging.debug('debug')
CRITICAL:root:critical
ERROR:root:error
WARNING:root:warning
INFO:root:info
level
———————
CRITICAL
ERROR
WARNING
INFO
DEBUG
20

21. level
level
———————
CRITICAL
ERROR
WARNING
INFO
DEBUG
level WARNING
21

22. Logger Handler
Logger Handlerfilter filter
formatter
config
level level
22

23. Logger
23

24. getLogger Logger
import logging
logging.basicConfig()
logger = logging.getLogger('mylogger')
logger.error('haha')
ERROR:mylogger:haha
24

25. Logger
root
app1 app2
app1.a app1.b app2.c
25

26. Logger
root
app1 app2
app1.a app1.b app2.c
import logging
logging.basicConfig()
a = logging.getLogger('app1.a')
a.error('haha')
ERROR:app1.a:haha
26

27. Logger
root
app1 app2
app1.a app1.b app2.c
27

28. Handler
Logger Handler
Logger filter filter
formatter
config
level level
28

29. log
format
29

30. format
import logging
logging.basicConfig(format='*** %(message)s ***’)
logging.error('haha')
*** haha ***
30

31. format
1
2
3
4
5
6
7
import logging
logging.basicConfig(
format='%(filename)s:%(lineno)s %(message)s’
)
logging.error('haha')
a.py:7 haha
a.py
31

32. format
import logging
logging.basicConfig(format='*** %(message)s ***')
logging.error('haha')
*** haha ***
32

33. format
import logging
logging.basicConfig(format='*** %(message)s ***')
logging.error('haha')
*** haha ***
33

34. format
import logging
logging.basicConfig(format='*** %(message)s ***')
logging.error('haha')
*** haha ***https://docs.python.org/3.5/library/logging.html#logrecord-attributes
34

35. Handler
Logger Handler
Logger filter filter
formatter
config
level level
35

36. log
36

37. handler
import logging
a = logging.getLogger('mylogger')
handler = logging.FileHandler('a.log')
a.addHandler(handler)
a.error('hahaha')
hahaha
a.log
37

38. handler
import logging
a = logging.getLogger('mylogger')
h1 = logging.FileHandler('1.log')
h2 = logging.FileHandler('2.log')
a.addHandler(h1)
a.addHandler(h2)
a.error('hahaha')
hahaha
1.log
hahaha
2.log
38

39. handler
StreamHandler DatagramHandler
FileHandler SysLogHandler
NullHandler NTEventLogHandler
WatchedFileHandler SMTPHandler
BaseRotatingHandler MemoryHandler
RotatingFileHandler HTTPHandler
TimedRotatingFileHandler QueueHandler
SocketHandler
https://docs.python.org/3.5/library/logging.handlers.html
39

40. Handler
Handler
Logger filter filter
formatter
config
level level
Logger
40

41. handler
format
41

42. format
a = logging.getLogger('mylogger')
h1 = logging.FileHandler('1.log')
h2 = logging.FileHandler('2.log')
h1.setFormatter(
logging.Formatter('*** %(message)s ***'))
h2.setFormatter(
logging.Formatter('%(levelname)s:%(message)s'))
a.addHandler(h1)
a.addHandler(h2)
a.error('haha')
*** haha ***1.log
ERROR:haha2.log
42

43. Handler
Logger Handler
Logger filter filter
formatter
config
level level
43

44. level
handler
44

45. level
a = logging.getLogger('mylogger')
h1 = logging.FileHandler('1.log')
h2 = logging.FileHandler('2.log')
h1.setLevel(logging.ERROR)
h2.setLevel(logging.WARNING)
a.addHandler(h1)
a.addHandler(h2)
a.error('error')
a.warning('warning')
error1.log
error
warning
2.log
45

46. Handler
Logger Handler
Logger filter filter
formatter
config
level level
46

47. Handler
Logger Handler
Logger filter filter
formatter
config
level level
Logger Handler level
log
47

48. Filter log
48

49. Filter
class IpFilter(logging.Filter):
def filter(self, record):
record.ip = '192.168.1.2'
return True
logging.basicConfig(format='[%(ip)s] %(message)s')
a = logging.getLogger('mylogger')
f = IpFilter()
a.addFilter(f)
a.error('hahaha')
49
record: LogRecord
log
log LogRecord

50. Filter
class IpFilter(logging.Filter):
def filter(self, record):
record.ip = '192.168.1.2'
return True
logging.basicConfig(format='[%(ip)s] %(message)s')
a = logging.getLogger('mylogger')
f = IpFilter()
a.addFilter(f)
a.error('hahaha')
50

51. Filter
class IpFilter(logging.Filter):
def filter(self, record):
record.ip = '192.168.1.2'
return True
logging.basicConfig(format='[%(ip)s] %(message)s')
a = logging.getLogger('mylogger')
f = IpFilter()
a.addFilter(f)
a.error('hahaha')
[192.168.1.2] hahaha
51

52. Handler
Logger Handler
Logger
formatter
config
level level
filter filter
52

53. handler
...
53

54. handler
54

55. Handler emit
class MyHandler(logging.Handler):
def __init__(self, widget):
super(MyHandler, self).__init__()
self._widget = widget
def emit(self, record):
msg = self.format(record)
cursor = self._widget.textCursor()
cursor.insertText(msg)
cursor.insertText('n')
55

56. QPlainTextEdit
class MyHandler(logging.Handler):
def __init__(self, widget):
super(MyHandler, self).__init__()
self._widget = widget
def emit(self, record):
msg = self.format(record)
cursor = self._widget.textCursor()
cursor.insertText(msg)
cursor.insertText('n')
PyQt
56

57. 57
app = QApplication(sys.argv)
a = logging.getLogger('a')
widget = QPlainTextEdit()
h = MyHandler(widget)
a.addHandler(h)
widget.show()
a.error('hihi')
a.warning('lol')
sys.exit(app.exec_())

58. Handler
Logger Handler
Logger
formatter
config
level level
filter filter
58

59. logging
...
59

60. dict
60

61. ...
f = logging.Formatter(‘*** %(name)s:%(message)s ***’)
my_handler = logging.FileHandler('a.log')
my_handler.setLevel(logging.DEBUG)
my_handler.setFormatter(f)
a = logging.getLogger('my_logger')
a.setLevel(logging.INFO)
a.addHandler(my_handler)
a.error('error')
a.info('info')
61

62. Dict Logging
f = logging.Formatter(‘*** %(name)s:%(message)s ***’)
my_handler = logging.FileHandler('a.log')
my_handler.setLevel(logging.DEBUG)
my_handler.setFormatter(f)
a = logging.getLogger('my_logger')
a.setLevel(logging.INFO)
a.addHandler(my_handler)
a.error('error')
a.info('info')
config = {
'version': 1,
'formatters': {
'my_formatter': {
'format': '*** %(name)s:%(message)s ***'
},
},
'handlers': {
'my_handler': {
'level': 'DEBUG',
'class': 'logging.FileHandler',
'filename': 'a.log',
'formatter': 'my_formatter',
}
},
'loggers': {
'my_logger': {
'level': 'INFO',
'handlers': ['my_handler'],
}
},
}
62

63. Dict Logging
f = logging.Formatter(‘*** %(name)s:%(message)s ***’)
my_handler = logging.FileHandler('a.log')
my_handler.setLevel(logging.DEBUG)
my_handler.setFormatter(f)
a = logging.getLogger('my_logger')
a.setLevel(logging.INFO)
a.addHandler(my_handler)
a.error('error')
a.info('info')
config = {
'version': 1,
'formatters': {
'my_formatter': {
'format': '*** %(name)s:%(message)s ***'
},
},
'handlers': {
'my_handler': {
'level': 'DEBUG',
'class': 'logging.FileHandler',
'filename': 'a.log',
'formatter': 'my_formatter',
}
},
'loggers': {
'my_logger': {
'level': 'INFO',
'handlers': ['my_handler'],
}
},
}
from logging.config import dictConfig
dictConfig(config)
63

64. ...
from logging.config import dictConfig
dictConfig(config)
a = logging.getLogger('my_logger')
a.error('error')
a.info('info')
64

65. 65

66. ...
f = logging.Formatter(‘*** %(name)s:%(message)s ***’)
my_handler = logging.FileHandler('a.log')
my_handler.setLevel(logging.DEBUG)
my_handler.setFormatter(f)
a = logging.getLogger('my_logger')
a.setLevel(logging.INFO)
a.addHandler(my_handler)
a.error('error')
a.info('info')
66

67. logging
f = logging.Formatter(‘*** %(name)s:%(message)s ***’)
my_handler = logging.FileHandler('a.log')
my_handler.setLevel(logging.DEBUG)
my_handler.setFormatter(f)
a = logging.getLogger('my_logger')
a.setLevel(logging.INFO)
a.addHandler(my_handler)
a.error('error')
a.info('info')
[formatters]
keys=my_formatter
[handlers]
keys=my_handler
[loggers]
keys=root,my_logger
[formatter_my_formatter]
format=*** %(name)s:%(message)s ***
[handler_my_handler]
level=DEBUG
class=FileHandler
formatter=my_formatter
args=('a.log',)
[logger_my_logger]
level=INFO
handlers=my_handler
qualname=my_logger
[logger_root]
handlers=
my_logging.cfg
67

68. logging
f = logging.Formatter(‘*** %(name)s:%(message)s ***’)
my_handler = logging.FileHandler('a.log')
my_handler.setLevel(logging.DEBUG)
my_handler.setFormatter(f)
a = logging.getLogger('my_logger')
a.setLevel(logging.INFO)
a.addHandler(my_handler)
a.error('error')
a.info('info')
[formatters]
keys=my_formatter
[handlers]
keys=my_handler
[loggers]
keys=root,my_logger
[formatter_my_formatter]
format=*** %(name)s:%(message)s ***
[handler_my_handler]
level=DEBUG
class=FileHandler
formatter=my_formatter
args=('a.log',)
[logger_my_logger]
level=INFO
handlers=my_handler
qualname=my_logger
[logger_root]
handlers=
my_logging.cfg
from logging.config import fileConfig
fileConfig('my_logging.cfg')
68

69. ...
from logging.config import fileConfig
fileConfig('my_logging.cfg')
a = logging.getLogger('my_logger')
a.error('error')
a.info('info')
69

70. 70

71. %(xxx)s
defaults
71

72. [formatters]
keys=my_formatter
[handlers]
keys=my_handler
[loggers]
keys=root,my_logger
[formatter_my_formatter]
format=*** %(name)s:%(message)s ***
[handler_my_handler]
level=DEBUG
class=FileHandler
formatter=my_formatter
args=('a.log',)
[logger_my_logger]
level=INFO
handlers=my_handler
qualname=my_logger
[logger_root]
handlers=
72

73. [formatters]
keys=my_formatter
[handlers]
keys=my_handler
[loggers]
keys=root,my_logger
[formatter_my_formatter]
format=*** %(name)s:%(message)s ***
[handler_my_handler]
level=DEBUG
class=FileHandler
formatter=my_formatter
args=('%(my_log_file)s',)
[logger_my_logger]
level=INFO
handlers=my_handler
qualname=my_logger
[logger_root]
handlers=
%(xxx)s
73

74. [formatters]
keys=my_formatter
[handlers]
keys=my_handler
[loggers]
keys=root,my_logger
[formatter_my_formatter]
format=*** %(name)s:%(message)s ***
[handler_my_handler]
level=DEBUG
class=FileHandler
formatter=my_formatter
args=('%(my_log_file)s',)
[logger_my_logger]
level=INFO
handlers=my_handler
qualname=my_logger
[logger_root]
handlers=
fileConfig(
'my_logging.cfg',
defaults={'my_log_file': 'a.log'}
)
defaults
74

75. ...
75

76. basicConfig
76

77. basicConfig
StreamHandler + default Formatter
root logger
level, format, filename, …
77

78. basicConfig
logging.basicConfig(level=logging.ERROR)
level
logging.basicConfig(format='*** %(message)s ***')
format
logging.basicConfig(filename='a.log')
filename
78

79. basicConfig
logging.basicConfig(
level=logging.ERROR,
format='*** %(message)s ***',
filename='a.log'
)
level format filename
79

80. Handler
Logger Handler
level
filter
level
filter
formatter
config
Logger
80

81. logging
log
81

82. LogRecord
logger.info('xxx') logger
level
logger filter
record
YES
YES
NO
NO
bye
bye
handler
YES
bye bye
NO
parent logger
YES
NO logger
propagate
parent logger
82

83. YES
handler
YES logger
propagate
YES
NO
bye
YES
NO
bye
handler
level
handler filter
record
83

84. https://docs.python.org/3.5/howto/logging.html#logging-flow
84

85. Basic Tutorial & Advanced Tutorial
https://docs.python.org/3.5/howto/logging.html
Logging Cookbook
https://docs.python.org/3.5/howto/logging-cookbook.html
Python Library Document
https://docs.python.org/3.5/library/logging.html
85

86. Thank You