How to hide a domain?

Question

Domain name market

I have a task to hide the full domain name by mask.
for example

https://toster.ru -> https://t***r.ru
http://google.com -> http://g***e.com

those. leave only the first and last letters of the name and leave the zone completely. Tried preg_replace, but something doesn't work. Can you help with the rule?

Answer 1

preg_replace('/^(https?:\/\/.).*(.\..*)$/','\1***\2', 'http://google.com');

So?