How to check if content of webpage has been changed?

Question

Basically I\'m trying to run some code (Python 2.7) if the content on a website changes, otherwise wait for a bit and check it later.

I\'m thinking of comparing

Answer 1

You should do an HTTP HEAD request (so you don't download the file) and look at the "Last-modified" header in the response.

import requests

response = requests.head(url)
datetime_str = response.headers["last-modified"]

And keep checking if that field changes in a while loop and compare the datetime difference.

I did a little program on Python to do that:

https://github.com/javierdechile/check_updates_http