Telegram AI Digest Bot

A serverless daily tech news digest bot powered by Google Gemini and delivered via Telegram. Runs automatically every morning via GitHub Actions — no server required.

How It Works

GitHub Actions (cron 08:00 IST)
  │
  ├─ Fetch   → RSS feeds (TechCrunch, Hacker News, The Verge, Wired)
  ├─ Dedupe  → Filter articles already sent (persisted in seen_urls.json)
  ├─ AI      → Google Gemini selects top 5 stories + 2-line summaries
  ├─ Format  → Telegram HTML with emoji categories
  └─ Send    → Telegram Bot API → your channel/chat

Setup

1. Create a Telegram Bot

1. Message @BotFather on Telegram
2. Run /newbot and follow the prompts
3. Copy the Bot Token
4. Add the bot to your channel as an Admin (or just start a chat with it)
5. Get your Chat ID — for a channel use @channelname, for a private chat use @userinfobot

2. Get a Gemini API Key

1. Go to Google AI Studio
2. Click Create API Key
3. Copy the key

3. Add GitHub Secrets

In your repo: Settings → Secrets and variables → Actions → New repository secret

Secret Name	Value
BOT_TOKEN	Your Telegram bot token
CHAT_ID	Your Telegram chat/channel ID
GEMINI_API_KEY	Your Google AI Studio API key

4. Deploy

Push to GitHub — the workflow runs automatically at 08:00 AM IST every day.

Local Development

cd backend-node

# Install dependencies
npm install

# Copy and fill in your credentials
cp .env.example .env
# Edit .env with your BOT_TOKEN, CHAT_ID, GEMINI_API_KEY

# Run directly with tsx (no build needed)
npm run dev

# Or build + run
npm run build && npm start

Manual Trigger

Go to your repo → Actions → Daily Telegram Digest → Run workflow

Configuration

You can optionally set these in .env or as GitHub Secrets:

Variable	Default	Description
RSS_FEEDS	TechCrunch, HN, Verge, Wired	Comma-separated RSS feed URLs
MAX_ARTICLES	10	Max articles passed to Gemini

Project Structure

backend-node/
├── src/
│   ├── config.ts              # Env var validation
│   ├── logger.ts              # Structured JSON logger
│   ├── main.ts                # Orchestration entry point
│   └── services/
│       ├── fetchNews.ts       # RSS fetching (multi-feed, timeout)
│       ├── dedupe.ts          # URL-hash deduplication
│       ├── aiProcessor.ts     # Gemini summarization
│       ├── formatter.ts       # Telegram HTML formatting
│       └── telegram.ts        # Telegram sender (retry + chunking)
├── .github/workflows/
│   └── daily.yml              # GitHub Actions cron workflow
├── seen_urls.json             # Dedup state (auto-updated by CI)
├── .env.example               # Environment variable template
└── README.md

Tech Stack

• Runtime: Node.js 20 (TypeScript, ESM)
• AI: Google Gemini 2.0 Flash via @google/genai
• RSS Parsing: fast-xml-parser
• Delivery: Telegram Bot API (native fetch, no axios)
• CI/CD: GitHub Actions (cron + manual dispatch)