welcome

Greet new chat members as they join a group and log member departures.

What it shows

OnMessageFilter matching Message.NewChatMembers to send a welcome message for each joiner
OnMessageFilter matching Message.LeftChatMember to log departures
OnMyChatMember to detect when the bot itself is added to or removed from a group

Required bot permissions

The bot must be an admin in the group (or at minimum have the "Read Messages" permission granted to non-admin bots via setMyDefaultAdminRights). Without this, Telegram does not forward service messages about member joins and leaves.

Running

export TELEGRAM_BOT_TOKEN=123456:ABC...
go run ./examples/welcome

Add the bot to a group, then have another user join or leave — the bot will greet joiners and log departures to stdout.