How can I implement Server-Sent Events in Node.js?

How can I implement Server-Sent Events in Node.js?

To implement Server-Sent Events (SSE) in Node.js, you can use the built-in HTTP module to create a server that sends updates to the client.

Can you provide a simple code example?

Sure! Here's a basic example:

const http = require('http');

http.createServer((req, res) => {
  res.writeHead(200, { 'Content-Type': 'text/event-stream', 'Cache-Control': 'no-cache', 'Connection': 'keep-alive' });
  setInterval(() => {
    res.write(`data: ${new Date().toLocaleTimeString()}\n\n`);
  }, 1000);
}).listen(3000);
console.log('SSE server running on http://localhost:3000');

What do I need to do on the client side to receive these events?

On the client side, you can use the EventSource API to listen for messages from the server:

const eventSource = new EventSource('http://localhost:3000');

eventSource.onmessage = function(event) {
  console.log('New message:', event.data);
};

Are there any limitations or considerations I should be aware of?

Yes, SSE works well for unidirectional data flow but is not supported in all browsers. Also, consider network issues and reconnection logic.