common.py

#-------------------------------------------------------------------------------
# Name:        module1
# Purpose:
#
# Author:      User
#
# Created:     04-11-2018
# Copyright:   (c) User 2018
# Licence:     <your licence>
#-------------------------------------------------------------------------------
# StdLib
import os
import logging
import logging.handlers
import datetime
# Remote libraries
# local




# logging setup
def setup_logging(log_file_path, timestamp_filename=True, max_log_size=104857600,console_level=logging.DEBUG):
    """Setup logging (Before running any other code)
    http://inventwithpython.com/blog/2012/04/06/stop-using-print-for-debugging-a-5-minute-quickstart-guide-to-pythons-logging-module/
    """
    assert( len(log_file_path) > 1 )
    assert( type(log_file_path) == type("") )
    global logger

    # Make sure output dir(s) exists
    log_file_folder =  os.path.dirname(log_file_path)
    if log_file_folder is not None:
        if not os.path.exists(log_file_folder):
            os.makedirs(log_file_folder)

    # Add timetamp for filename if needed
    if timestamp_filename:
        # http://stackoverflow.com/questions/8472413/add-utc-time-to-filename-python
        # '2015-06-30-13.44.15'
        timestamp_string = datetime.datetime.utcnow().strftime("%Y-%m-%d %H.%M.%S%Z")
        # Full log
        log_file_path = add_timestamp_to_log_filename(log_file_path,timestamp_string)

    logger = logging.getLogger()
    logger.setLevel(logging.DEBUG)
    # 2018-10-02 18:16:15,229 - INFO - f.auto_failover.py - ln.117 - Logging started.
    formatter = logging.Formatter("%(asctime)s - %(levelname)s - f.%(filename)s - ln.%(lineno)d - %(message)s")

    # File 1, log everything
    # https://docs.python.org/2/library/logging.handlers.html
    # Rollover occurs whenever the current log file is nearly maxBytes in length; if either of maxBytes or backupCount is zero, rollover never occurs.
    fh = logging.handlers.RotatingFileHandler(
        filename=log_file_path,
        # https://en.wikipedia.org/wiki/Binary_prefix
        # 104857600 100MiB
        maxBytes=max_log_size,
        backupCount=2,# Two files worth of logs should be plenty.
        )
    fh.setLevel(logging.DEBUG)# Store all messages in the logfile so we can debug problems
    fh.setFormatter(formatter)
    logger.addHandler(fh)

    # Console output
    ch = logging.StreamHandler()
    ch.setLevel(console_level)
    ch.setFormatter(formatter)
    logger.addHandler(ch)

    logging.info("Logging started. log_file_path = {0!r}".format(log_file_path))
    return logger

def add_timestamp_to_log_filename(log_file_path, timestamp_string):
    """Insert a string before a file extention"""
    base, ext = os.path.splitext(log_file_path)
    return base+"_"+timestamp_string+ext
# /logging setup






def main():
    pass

if __name__ == '__main__':
    main()