telegram_channel_backup

The idea is very simple: you have a Telegram channel and just want to automatically backup your posts to GitHub.

Sounds easy. But how to do this with less hassle and without registering of additional Telegram and GitHub Apps IDs? Just follow these steps.

Now it only backups text posts, post-images, text posts with images and also downloads your telegraph articles in html format. Update for backuping posts with other types of media will come later.

Usage

1. Create a Telegram bot and get its token

• In Telegram find @BotFather, Telegram’s tool for creating and managing bots.

• Use the /newbot command to create a new bot.

• @BotFather will ask you for a name and username, then generate an authentication token for your new bot.

  The 'name' of your bot is displayed in contact details and elsewhere.

  The 'username' is a short name, used in search, mentions and t.me links. Usernames are 5-32 characters long and not case sensitive – but may only include Latin characters, numbers, and underscores. Your bot's username must end in 'bot', like 'tetris_bot' or 'TetrisBot'.

  The 'token' is a string, like 110201543:AAHdqTcvCH1vGWJxfSeofSAs0K5PALDsaw, which is required to authorize the bot and send requests to the Bot API. Keep your token secure and store it safely, it can be used by anyone to control your bot.

  Unlike the bot’s name, the username cannot be changed later – so choose it carefully.

• Add newly created bot to your channel as subscriber or administrator.

2. Create a (private) repository for channel backup

3. Create a personal access token (lets call it AUTH)

Just follow the instructions. Be sure to grant repository read-and-write permissions for actions and contents. You can also restrict permissions to only this repository.

4. Add BOT and AUTH tokens to your channel backup repository as secrets

Follow the instructions and add AUTH_TOKEN and BOT_TOKEN secrets

5. Create an action workflow

• Copy code from action_workflow_example
• Replace CHANNEL_REPO and BRANCH placeholders with your names (13-14 lines)
• Action is triggered on schedule at 23:30 UTC every day (line 7). Look here if you want to change it.

How it works

Action workflow

• action is triggered on schedule at 23:30 UTC every day
• installs python-telegram-bot and PyGithub
• makes _posts folder for posts
• run backup_telegram_channel.py with usage of BOT_TOKEN
• run upload_to_github.py with usage of AUTH_TOKEN

backup_telegram_channel.py

• gets channel updates for last 24 hours and saves as dictionary of the newly created or the last version of updated posts, uses python-telegram-bot library

  python-telegram-bot is a wrapper of the Telegram Bot API. Incoming channel updates are stored on the server no longer than 24 hours. That's why action in the orkflo is triggered once every day. If you need more functionality, then look into full Telegram API, register new Telegram App and use api_id and an api_hash for authentification. This script should be rewritten for usage of another API.

• save all posts from dictionary in the YYYY-MM-DD-postId.md format in _posts folder

upload_to_github.py

• gets all files in your channel backup repository as a set
• commits and pushes all posts from _posts folder with right commit message (updated or created post)

(Optional, not used in the action workflow) backup_telegram_channel_history.py

If you already have a channel and there are already posts older than last 24 hours, then this optional script is for you. You need to have Python3 and Telegram Desktop installed. Telegraph and BeautifulSoup are used to prettify html string from Telegraph articles.

• Checkout this repository and install necessary dependancies:

  $ git clone https://github.com/CatUnderTheLeaf/telegram_channel_backup.git
  
  $ pip install PyGithub
  $ pip install 'telegraph[aio]'
  $ pip install beautifulsoup4
  
  # create folder for old posts in json format
  $ cd telegram_channel_backup
  $ mkdir json_dump
  

• Go to Telegram Desktop, open your channel, click on three dots sign in the upper right corner and select export chat history, select JSON as format and json_dump as path
• Convert posts and upload them to your repository:

  # convert json format to posts in the `YYYY-MM-DD-postId.md` format in `_posts` folder
  # json_dump is a folder with dumped history and images
  $ python backup_telegram_channel_history.py dump_dir=json_dump
  
  # replace placeholders for actual values
  $ python upload_to_github.py auth_token=$AUTH_TOKEN repo=$CHANNEL_REPO branch=$BRANCH