PHP Domain Parser is a Public Suffix List based domain parser implemented in PHP.

While there are plenty of excellent URL parsers and builders available, there are very few projects that can accurately parse a url into its component subdomain, registrable domain, and public suffix parts.

Consider the domain www.pref.okinawa.jp. In this domain, the public suffix portion is okinawa.jp, the registrable domain is pref.okinawa.jp, and the subdomain is www. You can't regex that.

Other similar libraries focus primarily on URL building, parsing, and manipulation and additionally include public suffix domain parsing. PHP Domain Parser was built around accurate Public Suffix List based parsing from the very beginning, adding a URL object simply for the sake of completeness.

You need:

• PHP >= 7.0 but the latest stable version of PHP is recommended
• the mbstring extension
• the intl extension
• the curl extension

• PSR-16

$ composer require jeremykendall/php-domain-parser

<?php

namespace Pdp;

use Psr\SimpleCache\CacheInterface;

final class Manager
{
    const PSL_URL = 'https://publicsuffix.org/list/public_suffix_list.dat';
    public function __construct(CacheInterface $cache, HttpClient $http)
    public function getRules(string $source_url = self::PSL_URL): Rules
    public function refreshRules(string $source_url = self::PSL_URL): bool
}

This class obtains, parses, caches, and returns a PHP representation of the PSL rules.

To work as intended, the Manager constructor requires:

• a PSR-16 Cache object to store the retrieved rules using a basic HTTP client.

• a HttpClient interface which exposes the HttpClient::getContent method which expects a string URL representation has its sole argument and returns the body from the given URL resource as a string.
  If an error occurs while retrieving such body a HttpClientException is thrown.

<?php

namespace Pdp;

interface HttpClient
{
    /**
     * Returns the content fetched from a given URL.
     *
     * @param string $url
     *
     * @throws HttpClientException If an errors occurs while fetching the content from a given URL
     *
     * @return string Retrieved content
     */
    public function getContent(string $url): string;
}

For advance usages you are free to use your own cache and/or http implementation.

By default and out of the box, the package uses:

• a file cache PSR-16 implementation based on the excellent FileCache which caches the local copy for a maximum of 7 days.
• a HTTP client based on the cURL extension.

<?php

public function getRules(string $source_url = self::PSL_URL): Rules

This method returns a Rules object which is instantiated with the PSL rules.

The method takes an optional $source_url argument which specifies the PSL source URL. If no local cache exists for the submitted source URL, the method will:

1. call Manager::refreshRules with the given URL to update its local cache
2. instantiate the Rules object with the newly cached data.

On error, the method throws an Pdp\Exception.

<?php

use Pdp\Cache;
use Pdp\CurlHttpClient;
use Pdp\Manager;

$manager = new Manager(new Cache(), new CurlHttpClient());
$rules = $manager->getRules('https://publicsuffix.org/list/public_suffix_list.dat');
$rules->resolve('www.bébé.be');

This method enables refreshing your local copy of the PSL stored with your PSR-16 Cache and retrieved using the Http Client. By default the method will use the Manager::PSL_URL as the source URL but you are free to substitute this URL with your own.
The method returns a boolean value which is true on success.

<?php

use Pdp\Cache;
use Pdp\CurlHttpClient;
use Pdp\Manager;

$manager = new Manager(new Cache(), new CurlHttpClient());
$manager->refreshRules('https://publicsuffix.org/list/public_suffix_list.dat');

It is important to always have an up to date PSL ICANN Section. In order to do so the library comes bundle with an auto-update script located in the bin directory.

$ php ./bin/update-psl

This script requires that:

• The Pdp\Installer class which comes bundle with this package
• The use of the Cache and HTTP Client implementations bundle with the package.

If you prefer using your own implementations you should:

1. Copy the Pdp\Installer class
2. Adapt its code to reflect your requirements.

In any cases your are required to register a cron with your chosen script to keep your data up to date

For example, below I'm using the Manager with

• the Symfony Cache component
• the Guzzle client.

Of course you can add more setups depending on your usage.

Be sure to adapt the following code to your own framework/situation. The following code is given as an example without warranty of it working out of the box.

<?php

use GuzzleHttp\Client as GuzzleClient;
use Pdp\HttpClient;
use Pdp\HttpClientException;
use Pdp\Manager;
use Symfony\Component\Cache\Simple\PDOCache;

final class GuzzleHttpClientAdapter implements HttpClient
{
    private $client;

    public function __construct(GuzzleClient $client)
    {
        $this->client = $client;
    }

    public function getContent(string $url): string
    {
        try {
            return $client->get($url)->getBody()->getContents();
        } catch (Throwable $e) {
            throw new HttpClientException($e->getMessage(), $e->getCode(), $e);
        }
    }
}

$dbh = new PDO('mysql:dbname=testdb;host=127.0.0.1', 'dbuser', 'dbpass');
$symfonyCache = new PDOCache($dbh, 'league-psl-icann', 86400);
$guzzleAdapter = new GuzzleHttpClientAdapter(new GuzzleClient());
$manager = new Manager($symfonyCache, $guzzleAdapter);
$manager->refreshRules();
//the rules are saved to the database for 1 day
//the rules are fetched using GuzzlClient

$rules = $manager->getRules();
$domain = $rules->resolve('nl.shop.bébé.faketld');
$domain->getDomain();            //returns 'nl.shop.bébé.faketld'
$domain->getPublicSuffix();      //returns 'faketld'
$domain->getRegistrableDomain(); //returns 'bébé.faketld'
$domain->getSubDomain();         //returns 'nl.shop'
$domain->isValid();              //returns false

In any case, you should setup a cron to regularly update your local cache.

<?php

namespace Pdp;

final class Rules
{
    public function __construct(array $rules)
    public function resolve(string $domain = null, string $type = Domain::UNKNOWN_DOMAIN): Domain
}

The Rules constructor expects a array representation of the Public Suffix List. This array representation is constructed by the Manager and stored using a PSR-16 compliant cache.

The Rules class resolves the submitted domain against the parsed rules from the PSL. This is done using the Rules::resolve method which returns a Pdp\Domain object. The method expect a valid domain and you can optionnally specify against which section of rules you want to validate the given domain. By default all section are used (ie PRIVATE_DOMAIN and ICANN_DOMAIN) if the submitted section is invalid or unknown, the resolver will fallback to use the entire list.

<?php

final class Domain
{

    const ICANN_DOMAIN = 'ICANN_DOMAIN';
    const PRIVATE_DOMAIN = 'PRIVATE_DOMAIN';
    const UNKNOWN_DOMAIN = 'UNKNOWN_DOMAIN';

    public function __construct(?string $domain = null, ?string $publicSuffix = null, string $type = self::UNKNOWN_DOMAIN);
    public function getDomain(): ?string
    public function getPublicSuffix(): ?string
    public function getRegistrableDomain(): ?string
    public function getSubDomain(); ?string
    public function isValid(): bool;
    public function isICANN(): bool;
    public function isPrivate(): bool;
}

The Domain getters method always return normalized value according to the domain status against the PSL rules.

Domain::isValid status depends on the PSL rules used. For the same domain, depending on the rules used a domain public suffix may be valid or not.

<?php

use Pdp\Cache;
use Pdp\CurlHttpClient;
use Pdp\Domain;
use Pdp\Manager;

$manager = new Manager(new Cache(), new CurlHttpClient());
$rules = $manager->getRules('https://raw.githubusercontent.com/publicsuffix/list/master/public_suffix_list.dat');
//$rules is a Pdp\Rules object

$domain = $rules->resolve('www.ulb.ac.be');
$domain->getDomain();            //returns 'www.ulb.ac.be'
$domain->getPublicSuffix();      //returns 'ac.be'
$domain->getRegistrableDomain(); //returns 'ulb.ac.be'
$domain->getSubDomain();         //returns 'www'
$domain->isValid();              //returns true
$domain->isICANN();              //returns true
$domain->isPrivate();            //returns false

//let's resolve the same URI againts the PRIVATE DOMAIN SECTION

$domain = $rules->resolve('www.ulb.ac.be', Domain::PRIVATE_DOMAIN);
$domain->getDomain();            //returns 'www.ulb.ac.be'
$domain->getPublicSuffix();      //returns 'be'
$domain->getRegistrableDomain(); //returns 'ac.be'
$domain->getSubDomain();         //returns 'www.ulb'
$domain->isValid();              //returns false
$domain->isICANN();              //returns false
$domain->isPrivate();            //returns false

Warning: Some people use the PSL to determine what is a valid domain name and what isn't. This is dangerous, particularly in these days where new gTLDs are arriving at a rapid pace, if your software does not regularly receive PSL updates, because it will erroneously think new gTLDs are not valid. The DNS is the proper source for this information. If you must use it for this purpose, please do not bake static copies of the PSL into your software with no update mechanism.

Contributions are welcome and will be fully credited. Please see CONTRIBUTING for details.

• Jeremy Kendall
• ignace nyamagana butera
• All Contributors

The MIT License (MIT). Please see License File for more information.

The HTTP adapter interface and the cURL HTTP adapter were inspired by (er, lifted from) Will Durand's excellent Geocoder project. His MIT license and copyright notice are below.

Copyright (c) 2011-2013 William Durand <[email protected]>

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is furnished
to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.

Portions of the PublicSuffixListManager and the DomainParser are derivative works of the PHP registered-domain-libs. Those parts of this codebase are heavily commented, and I've included a copy of the Apache Software Foundation License 2.0 in this project.