@exodo you never know, you might be able to do it... just take passport-facebook and change it to use passport-telegram? You might have to change a couple things here and there as well, but it might be quite easy...
/** * `TelegramStrategy` constructor. * * The Telegram authentication strategy authenticates requests by delegating to Telegram using their protocol: https://core.telegram.org/widgets/login * * Applications must supply a `verify` callback which accepts an `account` object, and then calls `done` callback sypplying a `user`, which should be set to `false` if the credentials are not valid. If an exception occurred, `error` should be set. * * More info here: https://core.telegram.org/widgets/login
This tells me that it doesn't use the OAuth 2.0 protocol. Do you have any ideas on strategies to implement this?