A real-time stock trading application that makes decisions based on the predictions made by the bot.

Features:

• Periodically Fetches stock data from the Polygon.io API
• Analyzes stock data and predicts whether to buy, sell, or observe (Bot activity)
• Allows users to view stock data and latest predictions by the bot
• Represents a dynamic chart of stock data and the actions made based on predictions. Each point on chart represents a stock transaction. (🔴 - Sell, 🟢 - Buy, ⚫ - Observe)
• Generates a report of stock transactions for a given number of transactions (CSV file)

Tech Stack

• Frontend
  • HTML
  • CSS
  • JavaScript
  • Chart.js
• Backend
  • Node.js
  • Express.js
  • MongoDB

Installation and Setup

1. Clone the repository
2. Install dependencies: npm install
3. Create a .env file in the root directory and add the following environment variables:
   • MONGODB_URI: MongoDB connection string
   • POLYGON_API_KEY: Polygon.io API key
4. Start the application: npm start
5. Open a browser and navigate to http://localhost:3000

Specifications and assumptions

• The bot makes predictions based on the stock data fetched from the Polygon.io API. (Data starts from October-2022). Data is fetched reguarly after 21 seconds (just to prevent the API rate limit).
• Price of for each day is averaged from the high and low prices.
• The bot predicts whether to buy, sell, or observe based on the price trend. Final decision to process the transcation depends on availabe balance and stocks owned.

Routes

Route	Method	Description	Controller Function	Query Parameters
/report	GET	Generates a report for a given number of transactions.	handleGenerateReport(req, res, num)	num: Number of transactions
/	GET	Serves the home page of the application.	handleGetHome(req, res)	None
/stock/fetch-new	GET	Fetches new stock data and latest predictions by the bot.	handleFetchNewRequest(req, res)	None
/stock/fetch-all	GET	Fetches all stock data, including historical data and predictions.	handleFetchAllRequest(req, res)	None

Controllers

Controller	Function	Description	Parameters	Return
report.js	handleGenerateReport	Generates a report of stock transactions for a given number.	req, res, num	CSV file containing transaction data
static.js	handleGetHome	Renders the home page of the application.	req, res	Renders the home view
stock.js	handleFetchNewRequest	Fetches new stock data and updates their status.	req, res	JSON with new stock data
stock.js	handleFetchAllRequest	Fetches all stock data and returns the latest transactions.	req, res	JSON with all stock data
stock.js	processTransaction	Processes a stock transaction based on predictions and balance.	stockData	Creates a new stock entry in DB
stock.js	fetchAvailableBalanceAndStocksHeld	Retrieves the current balance and stocks owned.	None	Object with balance and stocks

Models

The STOCK model stores each stock transaction. This data is accessed during report generation, transaction processing, and updating the frontend.

Field	Type	Description
stockSymbol	String	The symbol of the stock (e.g., AAPL, TSLA).
stockPrice	Number	The price of the stock at the time of the transaction.
tradeAction	String	The action taken: 'buy', 'sell', or 'observe'.
isNewStock	Boolean	Indicates if the stock is new (default: true).
tradeDate	Date	The date of the transaction (defaults to the current date).
availableBalance	Number	The available balance after the transaction.
stocksOwned	Number	The number of stocks owned after the transaction (default: 0).

Timestamps

The model includes timestamps for createdAt and updatedAt, which are automatically managed by Mongoose.

Services

Service	Function	Description	Parameters	Return
bot.js	analyzeStock	Analyzes stock data and predicts whether to buy, sell, or observe.	data	Prediction string ('buy', 'sell', or 'observe')
connectToDB.js	connect	Connects to MongoDB and initializes the database with a dummy entry.	url	Promise that resolves when connected or rejects on error
fetchLiveData.js	fetchStockData	Fetches stock data from the Polygon.io API for a given ticker.	ticker	Stock data object from the API or null on error
fetchLiveData.js	processStockData	Processes fetched stock data to extract relevant information.	data	Processed result object or default 'N/A' object
fetchLiveData.js	fetchDataAndProcess	Combines fetching and processing stock data.	ticker	Result object from processing function
fetchLiveData.js	startFetchingStockDataAndAnalyse	Starts a periodic fetch and analysis of stock data.	ticker	None (initiates a setInterval function)