Logging outputs to a text file

Question

can logging outputs which appear on the terminal be redirected to a text file? I have tried

                z = open('/mnt/sdc1/Ryan/Marx/newfile.txt'.format(file), 'w')
                sys.stdout= sys.stderr = z
                print ('Running the Algoritm Now for case {}'.format(file))
                run_liver_mpct_algorithms(data_paths, model_paths,[0], int(data_paths['batch_size']), data_paths['task_str']))
                z.close()

In th file z This gives me only the traceback of the error and print statements ,inside of the run_liver_mpct_algorithms there are many logging outputs which i would also like to go in the file.

Any ideas would be helpful,Thanks !

Do you have control over `run_liver_mpct_algorithms`? If yes, see `logging` library. If not, also look at this answer: https://stackoverflow.com/questions/19425736 — pawamoy, Mar 12 '18 at 11:52
Use the logging module from the stdlib and output redirections from your OS / shell... — bruno desthuilliers, Mar 12 '18 at 11:52

score 2 · Accepted Answer · answered Mar 12 '18 at 11:44

2

Why not use the logging module from the standard library? Here's a simple example:

import logging
log_file = 'my_log_file.log'
log_fh = logging.FileHandler(log_file)
log_sh = logging.StreamHandler(sys.stdout)
log_format = '%(asctime)s %(levelname)s: %(message)s'
# Possible levels: DEBUG, INFO, WARNING, ERROR, CRITICAL    
log_level = 'INFO' 
logging.basicConfig(format=log_format, level=log_level, 
    handlers=[log_sh, log_fh])

You create logging messages like this:

logging.info('This is a log message on level INFO')
logging.warning('This is a log message on level WARNING')

Messages will be written to the console and to the file you specified.

answered Mar 12 '18 at 11:44

uwain12345

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You could even dispense with the FileHandler and just use output redirections from the OS / shell. – bruno desthuilliers Mar 12 '18 at 11:53
@bruno desthuilliers: from my understanding of the question OP wants to do both console and file output. By leaving out the relevant log handler, it's easy to choose which kind of output you want. – uwain12345 Mar 12 '18 at 12:47
Don't know about Windows but on unix-type systems you can have both the console and redirection using `tee`. – bruno desthuilliers Mar 12 '18 at 12:49
So you're saying my approach is more portable? ;) – uwain12345 Mar 12 '18 at 13:00
Not necessarily - we'd need some input from a Windows power user ;) – bruno desthuilliers Mar 12 '18 at 13:26

Logging outputs to a text file

1 Answers1