Let's make a Music Bot [Part-3]

In Part -3 of the Telegram Python Bot series, we will be building an interactive bot that will send us songs from our playlists.

Let's make a Music Bot [Part-3]

Welcome to Part - 3 in the Telegram Python Bot series; in this post, we will be building an interactive bot that will send us songs from our playlists.

This Tutorial/Post is for educational purposes only.

Why make a music bot?

We listen to music every day, and no one hates music; it's something that everyone enjoys while going through different emotional phases of their day and life; before music streaming became a success, music used to be sold on vinyl disks and broadcasted over the radio on Radio Stations, nowadays everyone has their personally curated playlists on various platforms. Let's discuss how we will implement some of the online streaming features.

Options

  1. Random songs from the playlist chosen random
  2. Playlist in shuffle shuffle
  3. Random Shuffle of all the songs available random_shuffle
  4. Send all songs available all

The first three options will be based on user input, and the last is just sending all the data available.

Storage

We have two options in which we can send songs to the user

  1. Files from local storage
  2. Files from Telegram servers

Using local storage to store and serve our songs is an excellent idea if songs are already stored on the machine, but it has drawbacks.

  1. Takes up a lot of disk space
  2. While sending many songs, bandwidth and data transfer issues may arise.

The above two problems can be solved using the files from Telegram Servers, Telegram is a chat service that uses the cloud to provide multi-device support, all of our data is stored in a data centre, and each and every file on Telegram, when uploaded, is assigned a unique 64-bit client identifier called file_id, these files are stored on the servers and can be sent by referencing these file_id. We can upload any number of files and reference them; using this, we can overcome the two issues above; however, these file_id are unique to chats and bots alike. For example, we upload a file  bot1 and get file_id - hexa123quad We can't use this file_id to send the file from bot2. The bots are uniquely identified using API TOKENS, when a token is reset, all these files are lost, as in we lose access to the files though they might continue to exist on the servers until they are deleted as they are no longer in use, saving Telegram their server space. We'll be writing the bot script keeping this drawback in mind; this can be eliminated by using persistent data stores/spaces, which can be discussed in a later post but are currently out of scope in this post.

Making the bot

Requirements

  • A Telegram BOT API Token
  • Few songs/audio files on the local machine

Initial Setup

Setting up a virtual environment

Setting up a virtual environment helps us isolate our dependencies and keep track of them on a per-project basis. We can set up and activate our virtual environment on Linux-based machines using these two commands.

# python3 -m venv <- name of environment ->
python3 -m venv venv
source ./venv/bin/activate
setup virtual-env

Installing dependencies

pip3 install python-telegram-bot

### List installed lib/packages
pip3 list
### Save list of installed lib/packages to file
pip3 freeze >> requirements.txt
### Install dependencies from requirements.txt
pip3 install -r requirements.txt
essential pip commands

Please refer to PART-2 of this series to familiarise yourself with making a simple bot that echoes our message.

Working with Files

All music/audio files on Telegram can be identified as objects of Audio class in the telegram package, we need the file_id attribute of this file.

Handling Audio files.

Using Messagehandler let's filter all audio files, and file_id_command to handle it.

dp.add_handler(MessageHandler(Filters.audio, file_id_command))

Now, all audio files will be handled by this function; let's echo this message via the bot.

bot.send_message(chat_id=update.effective_user.id, text=f"{update.message.audio.file_id}")
Get file_id from music files

I'll be uploading some songs, and I will categorize them into 3 different playlists to demonstrate the multiple playlists' functionality, upload numerous songs and take the file_id and add them to the list playlist, this is a nested list, where each item in playlist is another list. Make sure you change the file_id.

playlist = [
	["CQACAgUAAxkBAANjYqUAAWP9cuxE7EgxTvTf-DG1IPRcAAJ0BgACVhYpVYcf3_AvxxpFJAQ",],
    ["CQACAgUAAxkBAANvYqUAAXISqEMcoFaCru-FpQ7TV7s6AAJ6BgACVhYpVbItmvoqnv5_JAQ",],
    ["CQACAgUAAxkBAANxYqUAAXRA6qTTIMbAPQ_LfeQ2jeb3AAJ7BgACVhYpVSuUG82IMlJvJAQ"],
]

Song Command

Using the song command, let's start to serve songs; we will provide 4 options, random, shuffle, random_shuffle, all in a keyboard fashion; Telegram provides keyboards in two ways.

  1. Telegram keyboard that replaces general keyboard.
  2. Inline keyboard - a keyboard that is shown in the chat itself.

We'll be using the Inline Keyboard, it provides a clean user experience and has callback functions. We'll be having two callbacks showing new options based on user input, to keep track of user data and use it in other functions we will be using a nested global dictionary.

  1. Options callback
  2. Playlist Callback

Inline Keyboards

Let's create the keyboard with InlineKeyboardButton and InlineKeyboardMarkup, InlineKeyboardButton is used to identify a button and InlineKeyboardMarkup is used to give information to the client for rendering the keyboard; the layout of the keyboard is similar to describing a matrix using lists.

#Defining Keyboards
main_options = [
    [InlineKeyboardButton(text="Random", callback_data="random")],
    [InlineKeyboardButton(text="Shuffle", callback_data="shuffle")],
    [InlineKeyboardButton(text="Random Shuffle", callback_data="random_shuffle")],
    [InlineKeyboardButton(text="All", callback_data="all")],
]

playlist_option = [
    [InlineKeyboardButton(text="Playlist 1", callback_data='0')],
    [InlineKeyboardButton(text="Playlist 2", callback_data='1')],
    [InlineKeyboardButton(text="Playlist 3", callback_data='2')],
]

#Creating Markups
main_options_markup = InlineKeyboardMarkup(main_options)
playlist_option_markup = InlineKeyboardMarkup(playlist_option)
Making InlineKeyboards 

Handling Callbacks

To handle callbacks from the InlineKeyboards we need a dedicated handler called the CallbackQueryHandler, since we have multiple handlers, we mention the callbacks that we can expect using the pattern argument, which accepts bitwise operations.

dp.add_handler(CallbackQueryHandler(options_choice, pattern="^random|shuffle|random_shuffle|all$"))
dp.add_handler(CallbackQueryHandler(playlist_choice, pattern="^0|1|2$"))
Flow

/song -> options -> playlists

Options and Playlist Callback Handler

When user chooses random or shuffle we provide them with playlist choice, for random_shuffle we ask for the number of songs as input and proceed to send songs. All the user choices are stored in the global dictionary.

Taking user choice

Using a message handler and Filters we'll accept only messages while ignoring commands, typecast them into int and store them in the global dict; let's also make sure that we only process user input when required using flags such as accept within the dict.

dp.add_handler(MessageHandler((Filters.text & (~Filters.command)), user_req))
def user_req(update, context):
    if data[update.effective_user.id]["accept"] == 0:
        data[update.effective_user.id]["num_songs"] = int(update.message.text)
        print(update.message.text)
        data[update.effective_user.id]["accept"] = 1
        send_songs(update, context)
Sending Songs

We will be using send_songs method and will be accessing all the data stored until now, to send songs as per the user choice, and use the random module to randomize the order of the list using the random.shuffle method.
To merge all the playlists, we can use the extend method creating a new list all with all the songs.

all = list()
# Using list comprehension
all.extend(song for play in playlist for song in play)
# regular way
# all.extend(playlist[0])
# all.extend(playlist[1])
# all.extend(playlist[2]
def send_songs(update, context):
    if (
        data[update.effective_user.id]["option"] == "random"
        or data[update.effective_user.id]["option"] == "shuffle"
        or data[update.effective_user.id]["option"] == "random_shuffle"
    ):
        
        if data[update.effective_user.id]["option"] == "random":
            # songs = random.shuffle(playlist[data[update.effective_user.id]["playlist"]])
            songs = playlist[data[update.effective_user.id]["playlist"]]
            random.shuffle(songs)
            random_songs = songs[0:data[update.effective_user.id]["num_songs"]]
            for _ in random_songs:
                bot.send_audio(chat_id=update.effective_user.id, audio=_)
        elif data[update.effective_user.id]["option"] == "shuffle":
            songs = playlist[data[update.effective_user.id]["playlist"]]
            random.shuffle(songs)
            for _ in songs:
                bot.send_audio(chat_id=update.effective_user.id, audio=_)
        elif data[update.effective_user.id]["option"] == "random_shuffle":
            all_songs = all.copy()
            random.shuffle(all_songs)
            songs = all_songs[0 : data[update.effective_user.id]["num_songs"]]
            for _ in songs:
                bot.send_audio(chat_id=update.effective_user.id, audio=_)
    elif data[update.effective_user.id]["option"] == "all":
        for song in all:
            bot.send_audio(chat_id=update.effective_user.id, audio=song)
send_songs
Demonstration

Conclusion

We've successfully built a bot that can send us songs stored on Telegram Servers while providing a neat user experience throughout the option selection process; using the high-level classes in python-telegram-bot , we can build bots faster, providing more functionality. I believe that by using the above example, you can make a great music bot based on existing features or create a new one from scratch. You can build much more interesting, functional and unique bots using this platform provided by Telegram; the only limits are our imaginations.

You can find the code on my Github Repository.

Thank you for reading until the end, and see you next time; until then, happy learning
~ Kalyan Mudumby