Localhost no longer recognized

[23pointsNorth]

Setup:
python3 -m pip install --upgrade validators==0.22.0

Code to reproduce:

import validators
validators.url("http://127.0.0.1:80/")
validators.url("http://localhost:80/")

Expected outcome:
Both calls to return true.

Similar to the other issue, this commit c43826c seems to comment the tests for localhost

[yozachar]

Hi @23pointsNorth, please refer #285 (comment)

[23pointsNorth]

Right, thanks for pointing it out. I remember the documentation noted that it was introduced as of 0.11.x as a new feature.

A problem with the suggested solution is that simple_host=True also allows for

>>> validators.url("http://l:8000/", simple_host=True)
True

which is not a valid "default" hostname. So in essence, we still need to regex localhost in the target URL?

[yozachar]

It is true, that l or 13 are not common hostnames, but they are valid though.

In a (W)LAN, I could have my hosts named as a, b, c, ... or even 1, 2, 3, ... etc. It's not a clever naming scheme (and not recommended) but definitely legal. So a GET http://13:8080 from host c to host 13 is quite valid indeed.

---

Currently URL validation accepts all of these parameters:

def url(
    value: str,
    /,
    *,
    skip_ipv6_addr: bool = False,
    skip_ipv4_addr: bool = False,
    may_have_port: bool = True,
    simple_host: bool = False,
    strict_query: bool = True,
    rfc_1034: bool = False,
    rfc_2782: bool = False,
):

It is possible to add another boolean parameter say only_localhost, but I think it might not be good for the following reasons:

• simple_host must be True for only_localhost to work. - complexity
• should only_localhost refer to literal localhost string or all hostnames defined in /etc/hosts? - confusion
• AFAIK, hostnames such as abc, xyz, etc. are very uncommon. - viability

---

Instead, if an user want to ensure that an URL is strictly localhost, one could:

from validators import url as is_valid_url
from urllib.parse import urlsplit

if is_valid_url(given_url, simple_host=False) and urlsplit(given_url).netloc == 'localhost' :
    # do something

[23pointsNorth]

Thanks, I understand the perspective, just assumed some stability of the API.

Happy for you to close the issues as resolved.

[yozachar]

Thanks for using validators. Feel free to ping this thread if any ideas pop up.