Tourmaline

Kang Asu

Tourmaline - Telegram Bot Framework For Crystal

Telegram Bot (and hopefully soon Client) API framework for Crystal. Based heavily off of Telegraf this Crystal implementation allows your Telegram bot to be written in a language that's both beautiful and fast. Benchmarks coming soon.

If you want to extend your bot by using NLP, see my other library Cadmium.

Installation
Add this to your application's shard.yml:

dependencies:
  tourmaline:
    github: watzon/tourmaline
    version: ~> 0.7.0

Usage

Basic usage

require "tourmaline/bot"

alias TGBot = Tourmaline::Bot

bot = TGBot::Client.new(ENV["API_KEY"])

bot.command(["start", "help"]) do |message|
  text = "Echo bot is a sample bot created with the Tourmaline bot framework."
  bot.send_message(message.chat.id, text)
end

bot.command("echo") do |message, params|
  text = params.join(" ")
  bot.send_message(message.chat.id, text)
end

bot.poll

Listening for events
Tourmaline has a number of events that you can listen for (the same events as Telegraf actually). The full list of events is as can be found in the documentation.

bot.on(:text) do |update|
  text = update.message.not_nil!.text.not_nil!
  puts "TEXT: #{text}"
end

Adding middleware
Middleware can be created by extending the Tourmaline::Bot::Middleware class. All middleware classes need to have a call(update : Update) method. The middleware will be called on every update.

class MyMiddleware < TGBot::Middleware

  # All middlware include a reference to the parent bot.
  # @bot : Tourmaline::Bot::Client

  def call(update : Update)
    if message = update.message
      if user = message.from_user
        if text = message.text
          puts "#{user.first_name}: #{text}"
        end
      end
    end
  end

end

bot.use MyMiddleware

Webhooks
Using webhooks is easy, even locally if you use the ngrok.cr package.

# bot.poll

bot.set_webhook("https://example.com/bots/my_tg_bot")
bot.serve("0.0.0.0", 3400)

# or with ngrok.cr

require "ngrok"

Ngrok.start({ addr: "127.0.0.1:3400" }) do |ngrok|
  bot.set_webhook(ngrok.ngrok_url_https)
  bot.serve("127.0.0.1", 3400)
end

Payments
You can now accept payments with your Tourmaline app! First make sure you follow the setup instructions here so that your bot is prepared to handle payments. Then just use the send_invoice, answer_shipping_query, and answer_pre_checkout_querymethods to send invoices and accept payments.

bot.command("buy") do |message, params|
  bot.send_invoice(
    message.chat.id,
    "Sample Invoice",
    "This is a test...",
    "123344232323",
    "YOUR_PROVIDER_TOKEN",
    "test1",
    "USD",
    bot.labeled_prices([{label: "Sample", amount: 299}, {label: "Another", amount: 369}]).to_json
  )
end

Games
Ability to create and run games with your Tourmaline Bot is a recent feature that hasn't been tested yet. Please use the issue trackerif you experience problems.

Kemal Middleware
Tourmaline provides middleware for Kemal, just in case you want to use Kemal as the server.

require "kemal"
require "tourmaline/kemal/tourmaline_handler"

require "./your_bot"

add_handler Kemal::TourmalineHandler.new(
  bot: YourBot.new,
  url: "https://something.com",
  path: "/bot-webhook/#{ENV["TGBOT_API_KEY"]}"
)

Kemal.run

Note: Telegram won't send webhook requests to non-ssl domains. This means that you need to be running your kemal server with ssl enabled. For local development this can be a pain, but it is made much easier with ngrok.cr.

Development
This currently supports the following features:

• Bot API
  • Implementation examples
  • Easy command syntax
  • Robust middleware system
  • Standard API queries
  • Stickers
  • Inline mode
  • Long polling
  • Webhooks
  • Payments
  • Games
• Client API (in development)

If you want a new feature feel free to submit an issue or open a pull request.

Contributing

1. Fork it ( https://github.com/watzon/tourmaline/fork )
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request

Contributors

• watzon Chris Watson - creator, maintainer

Download Tourmaline

Regards

Kang Asu