telegrambot.rb

#!/usr/bin/env ruby

require 'em-http-request'
require 'json'

def send_m(m, recipient)
  token = ''
  base = 'https://api.telegram.org/bot'
  uri = "#{base}#{token}/sendMessage"

  EM.run do
    req = EM::HttpRequest.new(uri).get query: {chat_id:recipient, text:m.reverse}

    req.callback do
      print "#{req.response_header.status}: send new message\n"
    end

    req.errback do
      print "#{req.response_header.status}: #{req.error}\n"
    end
  end
end

def update(offset)
  token = ''
  base = 'https://api.telegram.org/bot'
  uri = "#{base}#{token}/getUpdates"

  EM.run do
    req = EM::HttpRequest.new(uri).get query: {offset: offset}

    req.callback do
      hash = JSON.parse(req.response)
      result = hash['result']
      print "#{req.response_header.status} - #{result.count} messages\n" if result.count > 0

      result.each do |x|
        m = x['message']
        print "#{m['from']['username']}: #{m['text']}\n"

        send_m(m['text'], m['from']['id']) unless m['text'].nil?
      end

      if result.count > 0
        update(result.last['update_id'] + 1)
      else
        update(offset)
      end
    end

    req.errback do
      print "#{req.response_header.status}: #{req.error}\n"
      update(offset)
    end
  end
end

update(0)