How can I check whether a user is a member of a Telegram group?

Question

I'd like to use the Telegram API to confirm that a given user is a member of a named group. I can successfully authenticate as the user given their phone number and the code that they get sent, but beyond that I'm pretty lost. I thought I could start with client.contactsSearch with @groupname, but that returns me an empty vector.

I'm using the Kotlogram library from Scala, but it's just a thin wrapper around the MT protocol.

Answer 1

For Bot API, you can use getChatMember method.

The result will contain status for member, left, etc.