How do you add datetime to a logfile name?
Question:
When I create my logfile, I want the name to contain the datetime.
In Python you can get the current datetime as:
>>> from datetime import datetime
>>> datetime.now()
datetime.datetime(2012, 2, 3, 21, 35, 9, 559000)
The str version is
>>> str(datetime.now())
'2012-02-03 21:35:22.247000'
Not a very nice str to append to the logfile name! I would like my logfile to be something like:
mylogfile_21_35_03_02_2012.log
Is there something Python can do to make this easy? I am creating the log file as:
fh = logging.FileHandler("mylogfile" + datetimecomp + ".log")
Answers:
Yes. Have a look at the datetime API, in particular strftime
.
from datetime import datetime
print datetime.now().strftime("%d_%m_%Y")
You need datetime.strftime()
, this allows you to format the timestamp using all of the directives of C’s strftime()
. In your specific case:
>>> datetime.now().strftime('mylogfile_%H_%M_%d_%m_%Y.log')
'mylogfile_08_48_04_02_2012.log'
You could also use a TimedRotatingFileHandler
that will handle the date and the rollover every day (or whenever you want) for you.
from logging.handlers import TimedRotatingFileHandler
fh = TimedRotatingFileHandler('mylogfile', when='midnight')
By default the format will be depending on the rollover interval:
The system will save old log files by appending extensions to the filename. The extensions are date-and-time based, using the strftime format %Y-%m-%d_%H-%M-%S
or a leading portion thereof, depending on the rollover interval.
But you can modify that as showed here, by doing something like:
from logging.handlers import TimedRotatingFileHandler
fh = TimedRotatingFileHandler('mylogfile', when='midnight')
fh.suffix = '%Y_%m_%d.log'
from time import strftime
fh = logging.FileHandler(strftime("mylogfile_%H_%M_%m_%d_%Y.log"))
To print hour
, minutes
, day
, month
and year
, use the following statement
from datetime
import datetime
print datetime.now().strftime("%H_%M_%d_%m_%Y")
We can use datetime.now() to get current timestamp. Here is my code that I am using to create log file with timestamp –
import logging
from datetime import datetime
LOG_FILENAME = datetime.now().strftime('D:/log/logfile_%H_%M_%S_%d_%m_%Y.log')
for handler in logging.root.handlers[:]:
logging.root.removeHandler(handler)
logging.basicConfig(filename=LOG_FILENAME,level=logging.DEBUG)
logging.info('Forecastiong Job Started...')
logging.debug('abc method started...')
Another Solution using format():
#generates a date for a generic filename
import datetime
date_raw = datetime.datetime.now()
date_processed = "{}-{}-{}_{}-{}-{}".format(date_raw.year, date_raw.month,
date_raw.day, date_raw.hour, date_raw.minute, date_raw.second)
#example value: date_processed = 2020-1-7_17-17-48
I used this in my own project
edit: as I found out about f(ormatted)-strings, this would be another solution:
date_processed = f"{date_raw.year}-{date_raw.month}-{date_raw.day}_{date_raw.hour}-{date_raw.minute}-{date_raw.second}"
When I create my logfile, I want the name to contain the datetime.
In Python you can get the current datetime as:
>>> from datetime import datetime
>>> datetime.now()
datetime.datetime(2012, 2, 3, 21, 35, 9, 559000)
The str version is
>>> str(datetime.now())
'2012-02-03 21:35:22.247000'
Not a very nice str to append to the logfile name! I would like my logfile to be something like:
mylogfile_21_35_03_02_2012.log
Is there something Python can do to make this easy? I am creating the log file as:
fh = logging.FileHandler("mylogfile" + datetimecomp + ".log")
Yes. Have a look at the datetime API, in particular strftime
.
from datetime import datetime
print datetime.now().strftime("%d_%m_%Y")
You need datetime.strftime()
, this allows you to format the timestamp using all of the directives of C’s strftime()
. In your specific case:
>>> datetime.now().strftime('mylogfile_%H_%M_%d_%m_%Y.log')
'mylogfile_08_48_04_02_2012.log'
You could also use a TimedRotatingFileHandler
that will handle the date and the rollover every day (or whenever you want) for you.
from logging.handlers import TimedRotatingFileHandler
fh = TimedRotatingFileHandler('mylogfile', when='midnight')
By default the format will be depending on the rollover interval:
The system will save old log files by appending extensions to the filename. The extensions are date-and-time based, using the strftime format
%Y-%m-%d_%H-%M-%S
or a leading portion thereof, depending on the rollover interval.
But you can modify that as showed here, by doing something like:
from logging.handlers import TimedRotatingFileHandler
fh = TimedRotatingFileHandler('mylogfile', when='midnight')
fh.suffix = '%Y_%m_%d.log'
from time import strftime
fh = logging.FileHandler(strftime("mylogfile_%H_%M_%m_%d_%Y.log"))
To print hour
, minutes
, day
, month
and year
, use the following statement
from datetime
import datetime
print datetime.now().strftime("%H_%M_%d_%m_%Y")
We can use datetime.now() to get current timestamp. Here is my code that I am using to create log file with timestamp –
import logging
from datetime import datetime
LOG_FILENAME = datetime.now().strftime('D:/log/logfile_%H_%M_%S_%d_%m_%Y.log')
for handler in logging.root.handlers[:]:
logging.root.removeHandler(handler)
logging.basicConfig(filename=LOG_FILENAME,level=logging.DEBUG)
logging.info('Forecastiong Job Started...')
logging.debug('abc method started...')
Another Solution using format():
#generates a date for a generic filename
import datetime
date_raw = datetime.datetime.now()
date_processed = "{}-{}-{}_{}-{}-{}".format(date_raw.year, date_raw.month,
date_raw.day, date_raw.hour, date_raw.minute, date_raw.second)
#example value: date_processed = 2020-1-7_17-17-48
I used this in my own project
edit: as I found out about f(ormatted)-strings, this would be another solution:
date_processed = f"{date_raw.year}-{date_raw.month}-{date_raw.day}_{date_raw.hour}-{date_raw.minute}-{date_raw.second}"