Clear Updates

If you are importing the master branch you can use the Clear() method of the UpdatesChannel:

func main() {
	bot, err := tgbotapi.NewBotAPI("MyAwesomeBotToken")
	if err != nil {
		log.Panic(err)
	}

	bot.Debug = true

	log.Printf("Authorized on account %s", bot.Self.UserName)

	u := tgbotapi.NewUpdate(0)
	u.Timeout = 60

	updates, err := bot.GetUpdatesChan(u)

	// Optional: wait for updates and clear them if you don't want to handle
	// a large backlog of old messages
	time.Sleep(time.Millisecond * 500)
	updates.Clear()

	for update := range updates {
		if update.Message == nil {
			continue
		}
		// Add logic here
	}
}

Up to version 4.6 you have to do it manually:

func main() {
	bot, err := tgbotapi.NewBotAPI("MyAwesomeBotToken")
	if err != nil {
		log.Panic(err)
	}

	bot.Debug = true

	log.Printf("Authorized on account %s", bot.Self.UserName)

	u := tgbotapi.NewUpdate(0)
	u.Timeout = 60

	updates, err := bot.GetUpdatesChan(u)

	// Optional: wait for updates and clear them if you don't want to handle
	// a large backlog of old messages
	time.Sleep(time.Millisecond * 500)
	for len(updates) != 0 {
		<-updates
	}

	for update := range updates {
		if update.Message == nil {
			continue
		}
		// Add logic here
	}
}