Extract domain name from url Python

问题

I am tring to extract the domain names out of a list of urls. just like in Extract domain name from the url
My problem is that the urls can be about everything, few examples:
m.google.com => google
m.docs.google.com => google
www.someisotericdomain.innersite.mall.co.uk => mall
www.ouruniversity.department.mit.ac.us => mit
www.somestrangeurl.shops.relevantdomain.net => relevantdomain
www.example.info => example
And so on..
The diversity of the domains doesn't allow me to use a regex as shown in how to get domain name from URL (because my script will be running on real time network traffic, the regex will have to be enormous in order to catch all kinds of domains as mentioned).
Unfortunately my web research the didn't provide any efficient solution.
Does any one have an idea of how to do this ?
Any help will be appreciated !
Thank you

回答1:

Use tldextract which is more efficient version of urlparse, tldextract accurately separates the gTLD or ccTLD (generic or country code top-level domain) from the registered domain and subdomains of a URL.

>>> import tldextract
>>> ext = tldextract.extract('http://forums.news.cnn.com/')
ExtractResult(subdomain='forums.news', domain='cnn', suffix='com')
>>> ext.domain
'cnn'

回答2:

It seems you can use urlparse https://docs.python.org/3/library/urllib.parse.html for that url, and then extract the netloc.

And from the netloc you could easily extract the domain name by using split

回答3:

With regex, you could use something like this:

(?<=\.)([^.]+)(?:\.(?:co\.uk|ac\.us|[^.]+(?:$|\n)))

https://regex101.com/r/WQXFy6/5

Notice, you'll have to watch out for special cases such as co.uk.

来源：https://stackoverflow.com/questions/44021846/extract-domain-name-from-url-python