In today’s fast-paced digital landscape, the demand for instant updates and live interactions has driven the adoption of real-time web applications. Whether it’s live chat, real-time notifications, or collaborative tools, users expect instantaneous feedback from web applications.

Real-time communication refers to the ability of a web application to deliver data to the client as soon as it is available, without requiring manual refreshes or periodic polling. Technologies like WebSockets and Server-Sent Events (SSE) make this possible by enabling seamless communication between the client and the server.

This blog post will guide you on how to build real-time web applications with WebSockets and SSE. So, let’s get into the topic. 

What Are Real-Time Applications, and Where Are They Used?

Real-time applications are those that allow users to interact with data or other users in near-instantaneous fashion. These applications allow users to interact with data or other users almost instantaneously, creating a seamless and engaging experience.

Real-time applications are the backbone of our fast-paced digital lives. Take messaging apps like WhatsApp and Slack, for instance. These platforms enable you to send messages, photos, and videos in real-time, keeping you connected with friends, family, and colleagues. The immediate delivery and receipt of messages make conversations fluid and natural, as if you were talking face-to-face.

Then there are live sports scoreboards. Imagine watching a thrilling football match and getting updates on the score, player stats, and game highlights in real-time. These applications ensure you never miss a moment of the action, keeping you on the edge of your seat.

Stock market updates are another prime example. Traders rely on real-time data to make split-second decisions. These applications provide up-to-the-minute stock prices, trading volumes, and market trends, enabling investors to react promptly to market changes and seize opportunities.

Online gaming platforms also thrive on real-time interactions. Whether you're teaming up with friends in a multiplayer game or competing against players worldwide, real-time applications ensure smooth gameplay, instant reactions, and an immersive experience.

Consider collaborative tools like Google Docs and Trello. These platforms allow multiple users to work on the same document or project simultaneously, with changes reflected instantly. This real-time collaboration boosts productivity and enhances teamwork, making it easier to brainstorm ideas, track progress, and achieve goals.

Now that we know what web apps are, let’s get into different websockets to implement in web apps. 

Overview of WebSockets and Server-Sent Events (SSE)

WebSockets: WebSockets enable full-duplex communication, allowing the client and server to send and receive messages simultaneously over a single persistent connection.

SSE: SSE is a unidirectional protocol where the server pushes updates to the client over an HTTP connection. It’s lightweight and ideal for one-way communication.

Implementing WebSockets in a Real-Time Web App

Establishing a WebSocket Connection in a Rails Backend

To establish a WebSocket connection in Ruby on Rails, you can use Action Cable:

Backend Code:

Frontend Code (Using JavaScript):

Example: Chat Application

With Action Cable, you can create a chat app where users can send and receive messages in real time. Implement rooms by creating different streams for each chat room.

Handling WebSocket Connection Issues

• Reconnection: Use Action Cable’s automatic reconnection feature.
• Heartbeat Mechanism: Rails handles heartbeats internally to keep the connection alive.

Using Server-Sent Events (SSE) for One-Way Updates

SSE is ideal for sending one-way updates from the server to the client. It uses a simple HTTP connection and works seamlessly for lightweight updates like notifications or live data streams.

Setting Up SSE in Rails

Backend Code:

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Frontend Code:

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Real-World Examples of SSE

Live sports scores are a prime example of Server-Sent Events (SSE) in action. When you're following a live match, you want updates as they happen. SSE ensures that score changes, player statistics, and game highlights are pushed to your device in real-time without needing constant refreshes. This creates a seamless and immersive experience, keeping fans engaged and informed every second of the game.

Stock market updates leverage SSE to provide investors with the latest market data. In the fast-paced world of trading, every second counts. SSE enables real-time updates on stock prices, trading volumes, and market trends, allowing traders to make informed decisions quickly. The continuous data flow ensures that investors have access to the most current information, minimizing latency and enhancing the ability to respond to market changes promptly.

Real-time dashboards are essential tools for businesses to monitor and analyze key metrics. With SSE, data from various sources can be streamed directly to the dashboard, providing up-to-the-minute insights. Whether it's tracking website traffic, sales figures, or system performance, real-time dashboards powered by SSE enable businesses to make data-driven decisions quickly. This immediate access to critical information helps in identifying trends, addressing issues, and seizing opportunities as they arise.

When to Choose WebSockets vs. SSE

Imagine you're developing a live sports app. The app needs to update scores and stats instantaneously while also allowing users to chat with each other during the game.

WebSockets shine here for high-frequency, bidirectional updates. They enable real-time chat, allowing users to send and receive messages without delay. This ensures an interactive experience, where conversations flow smoothly, like in a live stadium.

SSE (Server-Sent Events), on the other hand, is perfect for delivering live scores and stats. It's lightweight and less resource-intensive, pushing updates from the server to clients seamlessly. This ensures that users receive real-time game updates with minimal latency, without overwhelming the server.

Wrap Up

Building real-time web applications with WebSockets and Server-Sent Events (SSE) transforms how users interact with data and each other. Real-time communication is now essential, driving seamless user experiences in various applications like chat, live updates, and collaborative tools. 

WebSockets enable full-duplex communication, perfect for dynamic, two-way interactions, while SSE is ideal for lightweight, server-driven updates. Combining these technologies ensures responsive and engaging applications. Embrace real-time communication to keep users connected, informed, and immersed in your digital experiences.

Ready to revolutionize your web application? Partner with TechDots, and let our expertise in real-time technologies elevate your project. 

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