StackFormation\ValueResolver\Stage\EnvironmentVariableWithFallback::invoke PHP Метод

    public function invoke($string)
    {
        $string = preg_replace_callback('/\\{env:([^:\\}\\{]+?):([^:\\}\\{]+?)\\}/', function ($matches) {
            $value = getenv($matches[1]);
            $value = $value ? $value : $matches[2];
            $this->valueResolver->getDependencyTracker()->trackEnvUsage($matches[1], true, $value, $this->sourceBlueprint, $this->sourceType, $this->sourceKey);
            return $value;
        }, $string);
        return $string;
    }