logger.py

import logging
import datetime
import random


class Singleton(type):
    _instances = {}

    def __call__(cls, *args, **kwargs):
        if cls not in cls._instances:
            cls._instances[cls] = super(Singleton, cls).__call__(*args, **kwargs)
        return cls._instances[cls]


class TimeHandler(metaclass=Singleton):
    def __init__(self):
        self.now = datetime.datetime.now()
        self.h_file_name = \
            'pipeline-' + \
            str(self.now.year) + "-" + \
            str(self.now.month) + "-" + \
            str(self.now.day) + "--" + \
            str(self.now.hour) + "-" + \
            str(self.now.minute) + "-" + \
            str(self.now.second) + "--" + \
            str(random.randint(0, 10000)) + '.log'
        self.handler = self.return_handler(self.h_file_name)

    @staticmethod
    def return_handler(log_name):
        # create a file handler
        handler = logging.FileHandler(log_name)
        handler.setLevel(logging.INFO)

        # create a logging format
        formatter = logging.Formatter('%(asctime)s - %(name)s - %(levelname)s - %(message)s')
        handler.setFormatter(formatter)
        return handler