Log log file to avoid re-running

Simply write a file when it is running.

If the status in the file is 'running' skip the run

If any exception, write to log as well.

import os

import time

def read_log(path):

    with open(path, 'r') as f:

        return f.read() 

def write_log(path, string):

    with open(path, 'w') as f:

        f.write(string)    

log_file = 'c:\\temp\\test.log'

try:

    if os.path.exists(log_file) and 'running' in read_log(log_file):

        print('i am already running')

    else:

        write_log(log_file, 'Status: running')

        #main job

        for i in range(10):

            print('doing sth {}'.format(i))

            time.sleep(1)

            # test exception

            # if i == 3:

            #     'abc'/2

        print('job finished')

        write_log(log_file, 'Status: finished')

except Exception as e:

    print('finished with exception {}'.format(str(e)))

    write_log(log_file, 'Exception: {}'.format(str(e)))