如何只下载新文件？

Question

所以，我有这个代码可以帮助我下载URL中的所有文件，但是每天都有一个新文件，我如何避免下载URL中的所有文件

for link in soup.select("a[href$='v2.pdf']"):
    filename = os.path.join(folder_location,link['href'].split('/')[-1])
    with open(filename, 'wb') as f:
        f.write(requests.get(urljoin(url,link['href'])).content)

Answer 1

从这个问题How do I list all files of a directory?您可以使用此代码列出所有当前文件和目录

from os import listdir
from os.path import isfile, join
mypath = './'
files = [f for f in listdir(mypath) if isfile(join(mypath, f))]

在列表中获得每个文件后，您可以在下载每个文件时检查每个文件

for link in soup.select("a[href$='v2.pdf']"):
    filename = os.path.join(folder_location,link['href'].split('/')[-1])
    if (not filename in files):
        with open(filename, 'wb') as f:
            f.write(requests.get(urljoin(url,link['href'])).content)