Crating an Apex Redirect via the PHP Library throws a "Domains must be an array" error

[deriknelvaimo]

Version

5.3.0

What happened

Trying to add Apex redirects to a service throws a "Domains must be an array" error even when domains are an array.
I am using this guide: https://www.fastly.com/documentation/reference/api/vcl-services/apex-redirect/

Sample Code (sensitive bits removed):

<?php

require_once(__DIR__ . '/vendor/autoload.php');
ini_set('display_errors', 0);

$config = Fastly\Configuration::getDefaultConfiguration()->setApiToken('REDACTED');
$apiInstance = new Fastly\Api\ApexRedirectApi(null, $config);

$options = [
    'service_id' => 'REDACTED',
    'version_id' => 1,
    'domains' => [
        'example.com' // redacted real domain
    ],
    'status_code' => 301,
    'feature_revision' => 1,
];

try {
    $result = $apiInstance->createApexRedirect($options);
    print_r($result);
} catch (Exception $e) {
    echo 'Exception when calling ApexRedirectApi->createApexRedirect: ', $e->getMessage(), PHP_EOL;
    print_r($options);
}

Returns:

Exception when calling ApexRedirectApi->createApexRedirect: [400] Client error: `POST https://api.fastly.com/service/REDACTED/version/1/apex-redirects` resulted in a `400 Bad Request` response:
{"msg":"Bad request","detail":"Domains must be an array"}

With Options Array:

Array
(
    [service_id] => REDACTED
    [version_id] => 1
    [domains] => Array
        (
            [0] => example.com //redacted real domain
        )

    [status_code] => 301
    [feature_revision] => 1
)