Scrappy — Amazon Price Tracker

A self-hosted Amazon price tracker that monitors product prices over time and sends email alerts when your target price is hit. Built with Python, FastAPI, SQLite, and React.

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Demo

[https://youtu.be/1Mk60u60mic?si=-QW72TLr7iP8EaX6]

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Features

• Track multiple Amazon products simultaneously
• Logs price history on every check and surfaces the lowest recorded price
• Email alerts via Gmail when a product hits your target price — with spam prevention so you only get one alert per day per product
• Automated background price checks via cron, runs every 6 hours
• Manual price check trigger from the dashboard
• Add, update target price, and delete tracked products from a clean React frontend

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Tech Stack

Layer	Technology
Backend	FastAPI, Python
Database	SQLite
Scraping	Requests, BeautifulSoup4
Email	smtplib, Gmail App Password
Frontend	React, Vite
Automation	Cron

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Project Structure

Scrappy/
├── scrapper.py        # Fetches product title and price from Amazon
├── database.py        # SQLite setup and all DB queries
├── emailer.py         # Sends price alert emails via Gmail
├── tracker.py         # Core logic — loops all products, checks prices, triggers alerts
├── app.py             # FastAPI backend serving all endpoints
├── .env               # Credentials (not committed)
├── tracker.log        # Cron output log
└── frontend/          # React + Vite frontend

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Setup

1. Clone and create virtual environment

git clone https://github.com/yourusername/scrappy.git
cd scrappy
python3 -m venv venv
source venv/bin/activate
pip install requests beautifulsoup4 python-dotenv fastapi uvicorn

2. Configure environment variables

Create a .env file in the root:

SENDER_EMAIL=yourgmail@gmail.com
APP_PASSWORD=xxxx xxxx xxxx xxxx
RECEIVER_EMAIL=yourgmail@gmail.com

To generate a Gmail App Password: Google Account > Security > 2-Step Verification > App Passwords.

3. Run the backend

uvicorn app:app --reload

4. Run the frontend

cd frontend
npm install
npm run dev

5. Set up cron for automated checks

crontab -e

Add this line:

0 */6 * * * cd /path/to/Scrappy && /path/to/Scrappy/venv/bin/python tracker.py >> /path/to/Scrappy/tracker.log 2>&1

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How It Works

1. User adds an Amazon product URL and sets a target price via the frontend
2. The backend scrapes the current price and saves it to the database
3. Every 6 hours, cron runs tracker.py which checks all tracked products
4. Each price check is logged to price_history — the lowest ever recorded is always available
5. If the current price is at or below the target, an email alert is sent
6. A last_alerted timestamp prevents duplicate alerts on the same day

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API Endpoints

Method	Endpoint	Description
GET	/products	Get all tracked products
POST	/products/add	Add a new product
DELETE	/products/{id}	Delete a product
POST	/products/{id}/update	Update target price
POST	/run-check	Manually trigger a price check

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Notes

• This project is intended for personal use
• Amazon's scraping tolerance varies — occasional blocks may occur
• Cron only runs while your machine is on