telegram-bot-api/docs/getting-started/README.md

Getting Started

This library is designed as a simple wrapper around the Telegram Bot API. It's encouraged to read Telegram's docs first to get an understanding of what Bots are capable of doing. They also provide some good approaches to solve common problems.

Installing

go get -u github.com/go-telegram-bot-api/telegram-bot-api/v5

A Simple Bot

To walk through the basics, let's create a simple echo bot that replies to your messages repeating what you said. Make sure you get an API token from @Botfather before continuing.

Let's start by constructing a new BotAPI.

package main

import (
	"os"

	tgbotapi "github.com/go-telegram-bot-api/telegram-bot-api/v5"
)

func main() {
	bot, err := tgbotapi.NewBotAPI(os.Getenv("TELEGRAM_APITOKEN"))
	if err != nil {
		panic(err)
	}

	bot.Debug = true
}

Instead of typing the API token directly into the file, we're using environment variables. This makes it easy to configure our Bot to use the right account and prevents us from leaking our real token into the world. Anyone with your token can send and receive messages from your Bot!

We've also set bot.Debug = true in order to get more information about the requests being sent to Telegram. If you run the example above, you'll see information about a request to the getMe endpoint. The library automatically calls this to ensure your token is working as expected. It also fills in the Self field in your BotAPI struct with information about the Bot.

Now that we've connected to Telegram, let's start getting updates and doing things. We can add this code in right after the line enabling debug mode.

	// Create a new UpdateConfig struct with an offset of 0. Offsets are used
	// to make sure Telegram knows we've handled previous values and we don't
	// need them repeated.
	updateConfig := tgbotapi.NewUpdate(0)

	// Tell Telegram we should wait up to 30 seconds on each request for an
	// update. This way we can get information just as quickly as making many
	// frequent requests without having to send nearly as many.
	updateConfig.Timeout = 30

	// Start polling Telegram for updates.
	updates := bot.GetUpdatesChan(updateConfig)

	// Let's go through each update that we're getting from Telegram.
	for update := range updates {
		// Telegram can send many types of updates depending on what your Bot
		// is up to. We only want to look at messages for now, so we can
		// discard any other updates.
		if update.Message == nil {
			continue
		}

		// Now that we know we've gotten a new message, we can construct a
		// reply! We'll take the Chat ID and Text from the incoming message
		// and use it to create a new message.
		msg := tgbotapi.NewMessage(update.Message.Chat.ID, update.Message.Text)
		// We'll also say that this message is a reply to the previous message.
		// For any other specifications than Chat ID or Text, you'll need to
		// set fields on the `MessageConfig`.
		msg.ReplyToMessageID = update.Message.MessageID

		// Okay, we're sending our message off! We don't care about the message
		// we just sent, so we'll discard it.
		if _, err := bot.Send(msg); err != nil {
			// Note that panics are a bad way to handle errors. Telegram can
			// have service outages or network errors, you should retry sending
			// messages or more gracefully handle failures.
			panic(err)
		}
	}

Congradulations! You've made your very own bot!

Now that you've got some of the basics down, we can start talking about how the library is structured and more advanced features.