Course Overview
This 3-day practical course equips web developers with the knowledge and skills to build real-time web applications using WebSockets and other communication technologies such as Server-Sent Events and WebRTC. Participants will explore low-latency bidirectional communication patterns, scalability strategies, and implementation with Node.js, Socket.IO, and WebSocket APIs.
Duration: 3 Days
Format: Instructor-led, hands-on coding labs, architectural deep dives, and real-time app implementation
Description
Course Outline
? Day 1: Foundations of Real-Time Communication
Session 1: Real-Time Web – Concepts & Use Cases
- Evolution of real-time web: polling → long polling → WebSockets
- Common use cases: chat apps, live dashboards, multiplayer games, collaborative tools
- Overview of transport protocols (HTTP, TCP, UDP)
Session 2: Introduction to WebSockets
- What are WebSockets? Full-duplex, persistent connections
- WebSocket lifecycle: handshake, open, message, close
- WebSocket API in the browser
Session 3: Building Your First WebSocket App
- Setting up a WebSocket server (Node.js + ws package)
- Writing a client to connect and send/receive messages
- Message handling and broadcasting
Lab Activities:
- Build a simple real-time chat app using vanilla WebSockets
- Monitor connection lifecycle and debug messages
- Handle JSON-based message protocols
? Day 2: Real-Time Frameworks & Messaging Patterns
Session 1: Using Socket.IO for Robust Real-Time Apps
- Why Socket.IO? Features beyond native WebSockets
- Rooms, namespaces, reconnection, and broadcasting
- Server-side setup and client integration
Session 2: Real-Time Messaging Patterns
- One-to-one, one-to-many, many-to-many
- Publish/subscribe pattern
- Handling user presence and status
Session 3: Real-Time Error Handling and Reconnection
- Dealing with disconnects, retries, and fallbacks
- Timeout strategies and heartbeat/ping-pong mechanisms
- Middleware and authentication for Socket.IO
Lab Activities:
- Create a collaborative whiteboard app with Socket.IO
- Implement rooms and private messaging
- Add user presence indicators and reconnection logic
? Day 3: Advanced Topics, Security & Deployment
Session 1: Scaling WebSockets for Production
- Horizontal scaling challenges
- Redis Pub/Sub with Socket.IO for multi-instance apps
- Load balancing and sticky sessions
Session 2: Security & WebSocket Best Practices
- Securing WebSocket connections (wss://, origin checks)
- Authentication using JWT or session cookies
- Rate limiting and DoS protection
Session 3: Alternative Real-Time Tech (Bonus)
- Server-Sent Events (SSE) vs WebSockets
- Introduction to WebRTC for peer-to-peer communication
- Integrating real-time updates with frontend frameworks (React/Vue)
Lab Activities:
- Secure WebSocket communication with HTTPS and token auth
- Scale an app using Redis adapter and test across multiple tabs
- Optional: Add real-time notifications with SSE
