Extract top domain from string php - php

Question

I need to extract the domain name out of a string which could be anything. Such as:
$sitelink="http://www.somewebsite.com/product/3749875/info/overview.html";
or
$sitelink="http://subdomain.somewebsite.com/blah/blah/whatever.php";
In any case, I'm looking to extract the 'somewebsite.com' portion (which could be anything), and discard the rest.

Answer 1

With parse_url($url)
<?php
$url = 'http://username:password#hostname/path?arg=value#anchor';
print_r(parse_url($url));
?>
The above example will output:
Array
(
[scheme] => http
[host] => hostname
[user] => username
[pass] => password
[path] => /path
[query] => arg=value
[fragment] => anchor
)
Using thos values
echo parse_url($url, PHP_URL_HOST); //hostname
or
$url_info = parse_url($url);
echo $url_info['host'];//hostname

Answer 2

here it is
<?php
$sitelink="http://www.somewebsite.com/product/3749875/info/overview.html";
$domain_pieces = explode(".", parse_url($sitelink, PHP_URL_HOST));
$l = sizeof($domain_pieces);
$secondleveldomain = $domain_pieces[$l-2] . "." . $domain_pieces[$l-1];
echo $secondleveldomain;
note that this is not probably the behavior you are looking for, because, for hosts like
stackoverflow.co.uk
it will echo "co.uk"
see:
http://publicsuffix.org/learn/
http://www.dkim-reputation.org/regdom-libs/
http://www.dkim-reputation.org/regdom-lib-downloads/ <-- downloads here, php included

Answer 3

2 complexe url
$url="https://www.example.co.uk/page/section/younameit";
or
$url="https://example.co.uk/page/section/younameit";
To get "www.example.co.uk":
$host=parse_url($url, PHP_URL_HOST);
To get "example.co.uk" only
$parts = explode('www.',$host);
$domain = $parts[1];
// ...or...
$domain = ltrim($host, 'www.')
If your url includes "www." or not you get the same end result, i.e. "example.co.uk"
Voilà!

Answer 4

You need package that uses Public Suffix List, only in this way you can correctly extract domains with two-, third-level TLDs (co.uk, a.bg, b.bg, etc.) and multilevel subdomains. Regex, parse_url() or string functions will never produce absolutely correct result.
I recomend use TLD Extract. Here example of code:
$extract = new LayerShifter\TLDExtract\Extract();
$result = $extract->parse('http://www.somewebsite.com/product/3749875/info/overview.html');
$result->getSubdomain(); // will return (string) 'www'
$result->getHostname(); // will return (string) 'somewebsite'
$result->getSuffix(); // will return (string) 'com'
$result->getRegistrableDomain(); // will return (string) 'somewebsite.com'

Answer 5

For a string that could be anything, new approach:
function extract_plain_domain($text) {
$text=trim($text,"/");
$text=strtolower($text);
$parts=explode("/",$text);
if (substr_count($parts[0],"http")) {
$parts[0]="";
}
reset ($parts);while (list ($key, $val) = each ($parts)) {
if (!empty($val)) { $text=$val; break; }
}
$parts=explode(".",$text);
if (empty($parts[2])) {
return $parts[0].".".$parts[1];
} else {
$num_parts=count($parts);
return $parts[$num_parts-2].".".$parts[$num_parts-1];
}
} // end function extract_plain_domain

Answer 6

You can use the Utopia Domains library (https://github.com/utopia-php/domains), it will return the domain TLD and public suffix based on Mozilla public suffix list (https://publicsuffix.org), it can be used as an alternative to the currently archived TLDExtract package.
You can use 'parse_url' function to get the hostname from your URL and than use Utopia Domains parser to get the correct TLD and join it together with the domain name:
<?php
require_once './vendor/autoload.php';
use Utopia\Domains\Domain;
$url = 'http://demo.example.co.uk/site';
$domain = new Domain(parse_url($url, PHP_URL_HOST)); // demo.example.co.uk
var_dump($domain->get()); // demo.example.co.uk
var_dump($domain->getTLD()); // uk
var_dump($domain->getSuffix()); // co.uk
var_dump($domain->getName()); // example
var_dump($domain->getSub()); // demo
var_dump($domain->isKnown()); // true
var_dump($domain->isICANN()); // true
var_dump($domain->isPrivate()); // false
var_dump($domain->isTest()); // false
var_dump($domain->getName().'.'.$domain->getSuffix()); // example.co.uk