78 lines
3.1 KiB
PHP

<?php
namespace UglyRobot\Infinite_Uploads\Aws\Credentials;
use UglyRobot\Infinite_Uploads\Aws\Exception\CredentialsException;
use UglyRobot\Infinite_Uploads\GuzzleHttp\Psr7\Request;
use UglyRobot\Infinite_Uploads\GuzzleHttp\Promise\PromiseInterface;
use UglyRobot\Infinite_Uploads\Psr\Http\Message\ResponseInterface;
/**
* Credential provider that fetches credentials with GET request.
* ECS environment variable is used in constructing request URI.
*/
class EcsCredentialProvider
{
const SERVER_URI = 'http://169.254.170.2';
const ENV_URI = "AWS_CONTAINER_CREDENTIALS_RELATIVE_URI";
const ENV_TIMEOUT = 'AWS_METADATA_SERVICE_TIMEOUT';
/** @var callable */
private $client;
/** @var float|mixed */
private $timeout;
/**
* The constructor accepts following options:
* - timeout: (optional) Connection timeout, in seconds, default 1.0
* - client: An EcsClient to make request from
*
* @param array $config Configuration options
*/
public function __construct(array $config = [])
{
$timeout = getenv(self::ENV_TIMEOUT);
if (!$timeout) {
$timeout = isset($_SERVER[self::ENV_TIMEOUT]) ? $_SERVER[self::ENV_TIMEOUT] : (isset($config['timeout']) ? $config['timeout'] : 1.0);
}
$this->timeout = (double) $timeout;
$this->client = isset($config['client']) ? $config['client'] : \UglyRobot\Infinite_Uploads\Aws\default_http_handler();
}
/**
* Load ECS credentials
*
* @return PromiseInterface
*/
public function __invoke()
{
$client = $this->client;
$request = new \UglyRobot\Infinite_Uploads\GuzzleHttp\Psr7\Request('GET', self::getEcsUri());
return $client($request, ['timeout' => $this->timeout, 'proxy' => ''])->then(function (\UglyRobot\Infinite_Uploads\Psr\Http\Message\ResponseInterface $response) {
$result = $this->decodeResult((string) $response->getBody());
return new \UglyRobot\Infinite_Uploads\Aws\Credentials\Credentials($result['AccessKeyId'], $result['SecretAccessKey'], $result['Token'], strtotime($result['Expiration']));
})->otherwise(function ($reason) {
$reason = is_array($reason) ? $reason['exception'] : $reason;
$msg = $reason->getMessage();
throw new \UglyRobot\Infinite_Uploads\Aws\Exception\CredentialsException("Error retrieving credential from ECS ({$msg})");
});
}
/**
* Fetch credential URI from ECS environment variable
*
* @return string Returns ECS URI
*/
private function getEcsUri()
{
$credsUri = getenv(self::ENV_URI);
if ($credsUri === false) {
$credsUri = isset($_SERVER[self::ENV_URI]) ? $_SERVER[self::ENV_URI] : '';
}
return self::SERVER_URI . $credsUri;
}
private function decodeResult($response)
{
$result = json_decode($response, true);
if (!isset($result['AccessKeyId'])) {
throw new \UglyRobot\Infinite_Uploads\Aws\Exception\CredentialsException('Unexpected ECS credential value');
}
return $result;
}
}