Crypto Tracker App

A full-stack cryptocurrency tracker built with React, Node.js, Express, and MongoDB.
The app fetches live crypto data from the CoinGecko API, displays it in a React dashboard, stores it in a database, and updates data automatically every 10min and every-hour using a cron job.

🚀 Features

• Displays top 10 cryptocurrencies with:
  • Currency Name
  • Current price
  • 24h price change
  • Market capitalization
  • Sorting Feature
  • Histoical Data(when clicked on coin name)
• Live fetching from CoinGecko API
• Stores current and historical data in MongoDB
• Scheduled cron job updates the database every 10min & 1-hour
• Clean and responsive React dashboard

Frontend runs on https://cryptoappav.netlify.app

Backend runs on https://crypto-app-u7rb.onrender.com

🛠 Tech Stack

Frontend:

• React.js
• axios
• chart.js & react-chartjs
• CSS

Backend:

• Node.js
• Express.js
• Axios (for API calls)
• node-cron (for scheduled tasks)
• mongoose & mongodb
• CORS & dotenv

Database:

• MongoDB

⚙️ Cron Job Explanation

The backend includes a cron job that runs every hour using node-cron.

• It automatically calls the CoinGecko API.
• Fetches the latest crypto prices and market data every 10min.
• Stores the latest data in the CurrentCrypto collection.
• Appends historical snapshots to HistoricalCrypto for trend tracking.

This ensures the frontend always displays up-to-date information without manual intervention.

⚡ Installation

Backend

cd backend
npm install
# setup .env
npm run dev

Frontend

cd frontend
npm install
npm start

🛠 API Endpoints

The backend exposes the following endpoints:

1️⃣ Get Current Top Cryptocurrencies

Endpoint: GET /api/cryptos

Description:
Returns the latest data for the top cryptocurrencies stored in the CurrentCrypto collection.
This includes:

• id — coin identifier
• name — coin name
• symbol — coin symbol
• current_price — latest price in USD
• market_cap — market capitalization
• price_change_percentage_24h — 24-hour price change percentage

Example Response:

[
[
    {
        "_id": "690b515b69c295516626a3e5",
        "id": "bitcoin",
        "name": "Bitcoin",
        "symbol": "btc",
        "current_price": 102522,
        "market_cap": 2044512432188,
        "price_change_percentage_24h": -1.11875,
        "last_updated": "2025-11-05T13:29:41.331Z",
        "__v": 0
    },
  ...
]

2️⃣Get Historical Data for a Coin

Endpoint: GET /api/historical/:coinid

Description:
Fetches historical snapshots for a specific cryptocurrency stored in the HistoricalCrypto collection. Replace :coinid with the coin's id (e.g., bitcoin).

• id — coin identifier
• name — coin name
• symbol — coin symbol
• current_price — latest price in USD
• market_cap — market capitalization
• price_change_percentage_24h — 24-hour price change percentage
• timestamp — time

Example Response:

[
    {
        "id": "bitcoin",
        "name": "Bitcoin",
        "symbol": "btc",
        "current_price": 104572,
        "market_cap": 2086033954479,
        "price_change_percentage_24h": -2.84248,
        "timestamp": "2025-11-04T07:24:08.205Z"
    },
  ...
]

📸 Screenshots

(Add screenshots of your React dashboard here)

Dashboard React :- (Crpto Table)

Dashboard React :- (Historical Data)

Dashboard MongoDB :-(Current Data)

Dashboard MongoDB :-(Historical Data)

Cron Job Code

👤 Author

Avinash