Resolving domain names

PHP comes with built-in functions for resolving IP addresses from a domain name:

• gethostbyname

• gethostbynamel

However the default implementation of these functions block execution. For this reason the Orolyn library includes the DnsResolver class.

Using the DNS Resolver

Calling the static method lookup will attempt to fetch all IP addresses associated with the domain name. Using getAddress on the entry result will fetch the first found IP address:

Example:

use Orolyn\Net\DnsResolver;

$entry = DnsResolver::lookup('google.com');

var_dump($entry->getAddress()?->toString());

Output:

string(14) "142.250.200.14"

Getting all IP addresses

Calling getAddressList will provide a list of all addresses associated with the domain name:

/** @var IList<IPAddress> */
$addresses = $entry->getAddressList();

Getting IP addresses asynchronously

Running multiple searches using the concurrency component enables multiple datagram connections to run without blocking each other, for example below we will fetch the first available IP address from each of the following domains:

use Orolyn\Net\DnsResolver;
use function Orolyn\Lang\Async;
use function Orolyn\Lang\Await;

Await(
    $task1 = Async(fn () => DnsResolver::lookup('google.com')),
    $task2 = Async(fn () => DnsResolver::lookup('stackoverflow.com')),
    $task3 = Async(fn () => DnsResolver::lookup('readthedocs.org')),
);

var_dump('Task 1: ' . $task1->getResult()->getAddress()->toString());
var_dump('Task 2: ' . $task2->getResult()->getAddress()->toString());
var_dump('Task 3: ' . $task3->getResult()->getAddress()->toString());

Output

string(23) "Task 1: 142.250.187.206"
string(22) "Task 2: 151.101.193.69"
string(19) "Task 3: 104.18.7.29"