dns

#!/usr/bin/env php
<?php

/**
 * This is the executable example of the DNS example given in README.md.
 */

declare(strict_types = 1);

require __DIR__ . '/../vendor/autoload.php';

use Recoil\React\ReactKernel;
use Recoil\Recoil;

/**
 * Resolve a name to an IP address.
 *
 * @param string                      $name     The name to resolve.
 * @param React\Dns\Resolver\Resolver $resolver The resolver to use.
 */
function resolveDomainName($name, React\Dns\Resolver\Resolver $resolver)
{
    try {
        $ip = yield $resolver->resolve($name);
        echo 'Resolved "' . $name . '" to ' . $ip . PHP_EOL;
    } catch (Exception $e) {
        echo 'Failed to resolve "' . $name . '" - ' . $e->getMessage() . PHP_EOL;
    }
}

// -----------------------------------------------------------------------------

ReactKernel::start(function () {
    $resolver = (new React\Dns\Resolver\Factory)->create(
        '8.8.8.8',
        yield Recoil::eventLoop()
    );

    // Yielding an array of coroutines executes them in parallel and waits
    // until all have returned a value.
    yield [
        resolveDomainName('recoil.io', $resolver),
        resolveDomainName('php.net', $resolver),
        resolveDomainName('probably-wont-resolve', $resolver),
    ];

    echo 'Done.' . PHP_EOL;
});