<?php

declare(strict_types=1);

namespace AsyncAws\Core;

/**

* Helper to safely read environment variables.

*

* @author Jérémy Derussé <[email protected]>

*

* @internal

*/

final class EnvVar

{

public static function get(string $name): ?string

{

if (isset($_ENV[$name])) {

// variable_order = *E*GPCS

return (string) $_ENV[$name];

} elseif (isset($_SERVER[$name]) && !\is_array($_SERVER[$name]) && 0 !== strpos($name, 'HTTP_')) {

// fastcgi_param, env var, ...

return (string) $_SERVER[$name];

} elseif (false === $env = getenv($name)) {

// getenv not thread safe

return null;

}

return $env;

}

}