How to Retrieve Parameters from Commands in a Ruby Telegram Bot

Other Questions Telegram bot
1

I’m developing a Telegram bot using Ruby and I’m looking for assistance on how to capture user input from commands. For instance, when a user types /invite John, I want the bot to extract the name “John” and include it in the response.

when "/invite"
  bot.api.send_message(chat_id: message.chat.id, text: "Inviting user")

Currently, the bot handles the basic commands but I’m unsure how to retrieve the parameter. My goal is that when a user sends /invite Sarah, the bot responds with “Inviting Sarah” and also logs the command in a text file.

In summary, I need to:

  1. Capture the name from the command
  2. Use it in the response
  3. Record the entire command into a file

Is there a method to analyze the message text and extract just the parameter?

2

You can also use regex for parameter extraction - it’s way more flexible when commands have weird spacing or multiple parameters.

when "/invite"
  if match = message.text.match(/\/invite\s+(.+)/)
    name = match[1].strip
    bot.api.send_message(chat_id: message.chat.id, text: "Inviting #{name}")
    
    # Append to log file
    File.open("bot_commands.txt", "a") { |f| f.puts "#{Time.now.strftime('%Y-%m-%d %H:%M:%S')}: #{message.text}" }
  else
    bot.api.send_message(chat_id: message.chat.id, text: "Usage: /invite [name]")
  end
end

The regex handles whitespace variations way better than basic string ops. The (.+) grabs everything after the command as one chunk, so “John Smith” works fine. Also throw timestamps in your log entries - makes tracking much easier.

3

just use message.text.gsub('/invite ', '') to strip the command and grab what’s left. works great when you need something quick without overcomplicating it.

4

Parse the message text directly to grab parameters. The message object has the full text with command and parameters. Here’s what I do in my bots:

when "/invite"
  command_parts = message.text.split(' ', 2)
  if command_parts.length > 1
    username = command_parts[1]
    response_text = "Inviting #{username}"
    
    # Log to file
    File.open("commands.log", "a") do |file|
      file.puts "#{Time.now}: #{message.text}"
    end
    
    bot.api.send_message(chat_id: message.chat.id, text: response_text)
  else
    bot.api.send_message(chat_id: message.chat.id, text: "Please specify a name to invite")
  end
end

Use split(' ', 2) - it separates command from parameter but keeps any spaces in the parameter. Always check if the parameter exists so you don’t get errors when users send incomplete commands.