Q: How does the script alert me when the price drops?
A: You define a BUY_PRICE threshold, compare the current price against it, and if the current price is at or below the threshold, the script sends an email alert using SMTP.
Q: How can the script accurately extract prices from Amazon’s page?
A: You inspect the page (or dump the HTML), note the specific CSS class (like “a-offscreen”) that holds the price, and use BeautifulSoup to target that element and extract its text.
Q: Which Python packages are essential to build this price tracker?
A: You’ll need: – requests for fetching page content – lxml for parsing HTML – BeautifulSoup (bs4) to extract specific elements like price and title
Q: Can I really make the tracker monitor any Amazon product I choose?
A: Absolutely! You simply copy the product URL from Amazon, plug it into your Python script, and the tracker will monitor that item’s price.
Q: How do you test the application to ensure it works correctly?
A: Once both backend and frontend are running, open two browser windows (one in incognito mode and one normal). Join the chat in both windows, exchange messages, and observe real-time updates appearing in each—this confirms correct functionality.
Q: How are user events (join, message, leave) handled in this app?
When a user joins, their name is stored and a “user-joined” event is emitted to other connected clients. Messages are sent using a “receive” event handled by client-side rendering logic. A “left” event is emitted and displayed when a user exits the chat.
Q: What are the high-level steps to build the chat application?
Create a project directory and initialize it with npm init Install the socket.io package Write backend logic in index.js, creating an HTTP server and integrating Socket.IO Set up client-side files (index.html and app.js) with UI and Socket.IO logic Run the application locally and test communication between browser windows.
Q: What tools and libraries are required to follow the tutorial?
A: You’ll need: Node.js — for the server-side runtime, Socket.IO — to enable real-time communication, Visual Studio Code (VS Code) — as the development environment. These tools set the foundation for setting up both backend and frontend components.
Q: What is Socket.IO and why is it used in this tutorial?
A: Socket.IO is a popular JavaScript library that enables real-time, bidirectional communication between clients and servers. It leverages WebSockets and includes fallback options like long polling, ensuring broader compatibility and event-driven architecture—ideal for building interactive chat applications
Q: What happens if the class doesn’t exist at runtime?
A: The code catches ClassNotFoundException and prints a friendly error—gracefully handling missing or misspelled class names.