Implementing a stock portfolio tracker

Implementing a Stock Portfolio Tracker Using jQuery

Introduction
Project Overview
Technologies Used
Setting Up the Environment
Designing the UI
Fetching Real-Time Stock Data
Managing User’s Portfolio
Displaying and Updating Data Dynamically
Implementing Buy and Sell Features
Adding Data Persistence (Local Storage)
Enhancing UI with jQuery Animations
Handling Errors and Edge Cases
Testing the Application
Deploying the Portfolio Tracker
Conclusion and Future Enhancements

1. Introduction

A stock portfolio tracker is a web application that allows users to track stock market investments in real-time. It helps users monitor stock prices, calculate profit/loss, and manage holdings efficiently. In this tutorial, we will build a stock portfolio tracker using jQuery along with AJAX for fetching real-time stock data.

2. Project Overview

The stock portfolio tracker will have the following features:

A search functionality to find stocks by ticker symbol.
Real-time stock price updates using an API.
A table displaying the user’s portfolio with stock names, prices, quantity, and total value.
Buy and sell options to update stock holdings.
Data persistence using local storage.
Basic chart visualization using Chart.js.

3. Technologies Used

HTML/CSS – To design the web page.
jQuery – To handle DOM manipulation, event handling, and AJAX requests.
AJAX – To fetch stock market data in real time.
Local Storage – To store user data persistently.
Chart.js – To visualize stock trends (optional).

4. Setting Up the Environment

Before starting, ensure you have:

A text editor like VS Code or Sublime Text.
A local web server or just a browser to test your application.
An API key from a stock market data provider like Alpha Vantage or Yahoo Finance.

Including Required Libraries

In the <head> section of index.html, include the following:

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Stock Portfolio Tracker</title>
    <script src="https://code.jquery.com/jquery-3.6.0.min.js"></script>
    <script src="https://cdn.jsdelivr.net/npm/chart.js"></script>
    <link rel="stylesheet" href="styles.css">
</head>
<body>

5. Designing the UI

Create a simple layout using HTML:

<body>
    <h1>Stock Portfolio Tracker</h1>

    <div id="search-stock">
        <input type="text" id="stock-symbol" placeholder="Enter Stock Symbol">
        <button id="add-stock">Add Stock</button>
    </div>

    <table id="portfolio-table">
        <thead>
            <tr>
                <th>Stock</th>
                <th>Price</th>
                <th>Quantity</th>
                <th>Total Value</th>
                <th>Actions</th>
            </tr>
        </thead>
        <tbody></tbody>
    </table>

    <canvas id="portfolio-chart"></canvas>

    <script src="script.js"></script>
</body>
</html>

6. Fetching Real-Time Stock Data

To get stock prices, use an API like Alpha Vantage:

const API_KEY = "YOUR_API_KEY";

function getStockData(symbol, callback) {
    $.ajax({
        url: `https://www.alphavantage.co/query?function=GLOBAL_QUOTE&symbol=${symbol}&apikey=${API_KEY}`,
        type: "GET",
        success: function(response) {
            const stock = response["Global Quote"];
            if (stock) {
                callback({
                    symbol: stock["01. symbol"],
                    price: parseFloat(stock["05. price"])
                });
            } else {
                alert("Stock not found!");
            }
        },
        error: function() {
            alert("Error fetching stock data.");
        }
    });
}

7. Managing User’s Portfolio

Create an array to store portfolio data:

let portfolio = [];

function addStock(symbol, quantity) {
    getStockData(symbol, function(stock) {
        let existingStock = portfolio.find(s => s.symbol === stock.symbol);
        if (existingStock) {
            existingStock.quantity += quantity;
        } else {
            portfolio.push({ ...stock, quantity });
        }
        updatePortfolio();
    });
}

8. Displaying and Updating Data Dynamically

Use jQuery to update the portfolio table dynamically:

function updatePortfolio() {
    $("#portfolio-table tbody").empty();
    portfolio.forEach(stock => {
        let totalValue = (stock.price * stock.quantity).toFixed(2);
        $("#portfolio-table tbody").append(`
            <tr>
                <td>${stock.symbol}</td>
                <td>${stock.price}</td>
                <td>${stock.quantity}</td>
                <td>${totalValue}</td>
                <td>
                    <button class="sell" data-symbol="${stock.symbol}">Sell</button>
                </td>
            </tr>
        `);
    });
}

9. Implementing Buy and Sell Features

Add event listeners to handle stock purchases:

$(document).on("click", "#add-stock", function() {
    let symbol = $("#stock-symbol").val().toUpperCase();
    addStock(symbol, 1);
});

To sell stocks:

$(document).on("click", ".sell", function() {
    let symbol = $(this).data("symbol");
    portfolio = portfolio.filter(stock => stock.symbol !== symbol);
    updatePortfolio();
});

10. Adding Data Persistence (Local Storage)

Save portfolio data so it persists after refresh:

function savePortfolio() {
    localStorage.setItem("portfolio", JSON.stringify(portfolio));
}

function loadPortfolio() {
    let storedData = localStorage.getItem("portfolio");
    if (storedData) {
        portfolio = JSON.parse(storedData);
        updatePortfolio();
    }
}

$(document).ready(loadPortfolio);

11. Enhancing UI with jQuery Animations

Add fade effects:

$("#add-stock").on("click", function() {
    $("#portfolio-table").fadeOut(200).fadeIn(500);
});

12. Handling Errors and Edge Cases

Validate stock symbols.
Prevent duplicate stocks.
Display error messages dynamically.

function showError(message) {
    $("#error").text(message).fadeIn().delay(3000).fadeOut();
}

13. Testing the Application

Test the following:

Adding/removing stocks.
Fetching real-time prices.
Handling API failures.

14. Deploying the Portfolio Tracker

Upload the project to GitHub Pages or Netlify.
Use a server-side solution like Node.js for security.

This jQuery-based stock tracker provides:

Real-time stock tracking.
Portfolio management.
Data persistence.

Future Enhancements:

Authentication: Allow users to log in and save portfolios.
Advanced Charting: Use Chart.js to visualize stock trends.
Auto-refresh: Fetch stock data every few seconds.

Final Thoughts

This project is a great introduction to jQuery and AJAX, making it easy to fetch and display real-time data dynamically. Let me know if you need further refinements!