Create a filename with the epoch time / Parse an epoch-filename.

fname_with_epoch.py

#!/usr/bin/env python3
import re
import time
from datetime import datetime, timezone


class FnameWithEpoch:
    """Create a filename with the epoch time / Parse an epoch-filename.
    Reference:
        File Naming Conventions
        https://datamanagement.hms.harvard.edu/plan-design/file-naming-conventions
    """

    @staticmethod
    def fname_with_epoch(prefix, suffix):
        """Create a filename in "prefix_current-epoch_suffix" format.
        Args:
            prefix (str): Prefix of filename.
            suffix (str): Suffix of filename.
        Returns:
            str: Filename in "prefix_epoch_suffix" format.
        """
        now_epoch = int(time.time() * 1000)  # milliseconds
        return f'{prefix}_{now_epoch}{suffix}'

    @staticmethod
    def epoch_fname_to_dttm(fname, trunk=3):
        """Parse prefix_epoch-msec.suffix -> prefix_yyyymmddHHMMSSmsec.suffix in UTC.
        Args:
            trunk (int): Number of chars to be truncated from the dttm string's tail.
            fname (str): Filename in "prefix_epoch_suffix" format.
        Returns:
            str: Filename in "prefix_yyyymmddHHMM.suffix" format.
        Example:
            data_0000003600123.txt -> data_19700101010000123.txt
        Reference:
            Format a datetime into a string with milliseconds
            https://stackoverflow.com/a/18406412/11042987
        """
        pattern = re.compile(r'\D(\d{13})\D')  # epoch time in milliseconds
        pattern_found = pattern.search(fname)
        if pattern_found:
            epoch_string = pattern_found.group(1)
            dttm_string = datetime.fromtimestamp(
                int(epoch_string) / 1000, timezone.utc).strftime('%Y%m%d%H%M%S%f')[:int(-trunk)]
            new_name = fname.replace(epoch_string, dttm_string)
            print(f'\033[93mRenamed:  {fname} -> {new_name}')
            return new_name
        else:
            return fname


def menu():
    print('''
\033[93mMENU
[C]reate fname: New filename in "prefix_current-epoch_suffix" format.
[P]arse fname : "prefix_epoch-msec.suffix" -> "prefix_yyyymmddHHMMSSmsec.suffix".
\033[0m''', end='')
    res = input('Create fname [C] or Parse fname [P]? >> ').lower()

    # noinspection PyCompatibility
    match res:
        case 'c':
            return FnameWithEpoch.fname_with_epoch(input('Prefix? >> '), input('Suffix? >> '))
        case 'p':
            return FnameWithEpoch.epoch_fname_to_dttm(input('Filename? >> '))
        case _:
            raise ValueError(f'Invalid input: {res}')


if __name__ == '__main__':
    print(menu())