Integrating the official Telegram Login Widget allows users to authenticate on a web application using their Telegram account. When a user authorizes via the widget, Telegram passes authentication parameters (such as id , first_name , username , auth_date , and hash ) back to your specified redirect URL or JavaScript callback. In this tutorial, we will construct a backend validation mechanism in PHP and implement it inside a Yii2 application controller. We will compute the expected HMAC-...