如何在 Python 中将日期时间保存到文件以用于脚本自动化

Question

我正在创建一个脚本，该脚本会定期为服务器抓取已添加的“新”文件。为此，我希望将上次脚本执行的日期时间存储在一个文件中，以便脚本可以处理自该日期时间以来的“所有新文件”。最终目标是通过 Windows 任务计划程序定期运行此脚本。

我可以使用下面的代码来做这个的基本版本。但是，我希望有一种更简洁、更短或更健壮的方法来实现这一目标。欢迎任何建议！

import datetime

fmt = "%Y-%m-%d %H:%M:%S"

last_run = ""

# try loading the datetime of the last run, else print warning

try:

    with open("last_run.txt", mode="r") as file:

        last_run = datetime.datetime.strptime(file.read(), fmt)

        print(last_run)

except:

    print("no file available")

# ... run script code using the last_run variable as input ...

# update the script execution time and save it to the file

with open("last_run.txt", mode="w") as file:

    file.write(datetime.datetime.now().strftime(fmt))

Answer 1

您的解决方案看起来不错。我唯一想建议的是在两个单独的函数中取出读取和写入上次运行时间戳逻辑，并将这两个函数移动到一个单独的模块文件中。这与上述回复中@Tomalak 的建议相同。下面是代码示例。模块文件：last_run.pyimport datetimefmt = "%Y-%m-%d %H:%M:%S"def get_last_run_time_stamp():    """    Get last run time stamp\n    ====\n    When this function called\n    AND  last_run.txt file is present\n    Then open the file and read the time-stamp stored in it\n    ====\n    When this function is called\n    AND last_run.txt file is not present\n    Then print the following message on console: "last_run.txt file is not available"\n    """    # try loading the datetime of the last run, else print warning    try:        with open("last_run.txt", mode="r") as file:            return datetime.datetime.strptime(file.read(), fmt)    except:        # Return with current time-stamp if last_run.txt file is not present        return datetime.datetime.now().strftime(fmt)# ... run script code using the last_run variable as input ...def save_last_run_time_stamp():    """    Save last run time stamp\n    ====\n    When this function called\n    AND  last_run.txt file is present\n    Then Open the file, save it with current time stamp and close the file\n    ====\n    When this function called\n    AND  last_run.txt file is not present\n    Then Create the file, open the file, save it with current time stamp and close the file\n    """    # update the script execution time and save it to the file    with open("last_run.txt", mode="w") as file:        current_timestamp = datetime.datetime.now().strftime(fmt);        file.write(current_timestamp)然后，下面是 schedular 配置和运行的文件：run_latest_scaped_files.py,import last_run as lrlast_run = lr.get_last_run_time_stamp()print(last_run)# ... run script code using the last_run variable as input ...lr.save_last_run_time_stamp()就是这样！！！