urlparse不会引发无效网址的异常

Question

I have the following code, which is supposed to check if an entered url is valid:

#!/usr/bin/env python3

import sys
import urllib.parse

# ...

def checkValidURL(someURL):
    try:
        parsed_url = urllib.parse.urlparse(someURL)
        isURL = True
    except ValueError:
        print("Invalid URL!")
        sys.exit(0)

# ...

if __name__ == "__main__":
    checkValidURL(someURL)

If an invalid URL is entered, for example: someURL="http://ijfjiör@@@a:43244434::" it should raise a ValueError as described here :

Characters in the netloc attribute that decompose under NFKC normalization (as used by the IDNA encoding) into any of /, ?, #, @, or : will raise a ValueError. If the URL is decomposed before parsing, no error will be raised.

However, no exception is raised and the URL seems to be valid.

Is there anything I am doing wrong or is there any other way to check the validity of an URL?

Answer 1

Your URL doesn't decompose into a string which contains a prohibited character, so the quotation is not at all relevant here.

The language in the quote is strictly about disallowing the use of internationalized domain name encoding like http://xn--foo/ to produce something like http://?/ and since you are not doing that here, no ValueError is generated or indeed to be expected.

(Sorry, not in a place where I can create a genuine working example.)

Answer 2

I'm not sure if the python validators module would be a better fit for your use case?

$ python3

>>> 
>>> 
>>> import validators
>>> 
>>> validators.url("http://ijfjiör@@@a:43244434::")
ValidationFailure(func=url, args={'value': 'http://ijfjiör@@@a:43244434::', 'public': False})
>>> 
>>> validators.url("http://www.google.com:8080/")
True
>>> 
>>> validators.url("http://www.我愛你.com:8080/你好")
True