Get subdomain from URL using Python

We can use https://github.com/john-kurkowski/tldextract for this problem...

It's easy.

>>> ext = tldextract.extract('http://forums.bbc.co.uk')
>>> (ext.subdomain, ext.domain, ext.suffix)
('forums', 'bbc', 'co.uk')

tldextract separate the TLD from the registered domain and subdomains of a URL.

Installation

pip install tldextract

For the current question:

import tldextract

address = 'http://lol1.domain.com:8888/some/page'
domain = tldextract.extract(address).domain
print("Extracted domain name : ", domain)

The output:

Extracted domain name :  domain

In addition, there is a number of examples which is extremely related with the usage of tldextract.extract side.

First of All import tldextract, as this splits the URL into its constituents like: subdomain. domain, and suffix.

import tldextract

Then declare a variable (say ext) that stores the results of the query. We also have to provide it with the URL in parenthesis with double quotes. As shown below:

ext = tldextract.extract("http://lol1.domain.com:8888/some/page")

If we simply try to run ext variable, the output will be:

ExtractResult(subdomain='lol1', domain='domain', suffix='com')

Then if you want to use only subdomain or domain or suffix, then use any of the below code, respectively.

ext.subdomain

The result will be:

'lol1'

ext.domain

The result will be:

'domain'

ext.suffix

The result will be:

'com'

Also, if you want to store the results only of subdomain in a variable, then use the code below:

Sub_Domain = ext.subdomain

Then Print Sub_Domain

Sub_Domain

The result will be:

'lol1'

Using python 3 (I'm using 3.9 to be specific), you can do the following:

from urllib.parse import urlparse

address = 'http://lol1.domain.com:8888/some/page'

url = urlparse(address)

url.hostname.split('.')[0]

import re

def extract_domain(domain):
   domain = re.sub('http(s)?://|(\:|/)(.*)|','', domain)
   matches = re.findall("([a-z0-9][a-z0-9\-]{1,63}\.[a-z\.]{2,6})$", domain)
   if matches:
       return matches[0]
   else:
       return domain

def extract_subdomains(domain):
   subdomains = domain = re.sub('http(s)?://|(\:|/)(.*)|','', domain)
   domain = extract_domain(subdomains)
   subdomains = re.sub('\.?'+domain,'', subdomains)
   return subdomains

Example to fetch subdomains:

print(extract_subdomains('http://lol1.domain.com:8888/some/page'))
print(extract_subdomains('kota-tangerang.kpu.go.id'))

Outputs:

lol1
kota-tangerang

Example to fetch domain

print(extract_domain('http://lol1.domain.com:8888/some/page'))
print(extract_domain('kota-tangerang.kpu.go.id'))

Outputs:

domain.com
kpu.go.id

Standardize all domains to start with www. unless they have a subdomain.

from urllib.parse import urlparse
    
def has_subdomain(url):
    if len(url.split('.')) > 2:
        return True
    else:
        return False 

domain = urlparse(url).netloc
        
if not has_subdomain(url):
        domain_name = 'www.' + domain
        url = urlparse(url).scheme + '://' + domain