Middleware to stream server-sent events to the client. Browsers that don't support the EventSource interface will fall back to a hidden iframe.
Here is a simple express app that broadcasts a timestamp every 10 seconds.
var express = require('express');
var sendevent = require('sendevent');
var app = express();
// create a middlware that handles requests to `/eventstream`
var events = sendevent('/eventstream');
app.use(events);
// serve an empty page that just loads the browserify bundle
app.get('/', function(req, res) {
res.end('<script src="/bundle.js"></script>');
});
// broadcast data to all connected clients every 10 seconds
setInterval(function() {
events.broadcast({ time: Date.now() });
}, 10000);
// if needed you can also talk to individual clients
events.on('connect', function(client) {
client.send({ greeting: 'hello number ' + client.id });
});
// and get notified when they disconnect
events.on('disconnect', function(client) {
console.log('client %d disconnected', client.id);
});
If you use browserify you can simply require sendevent
module:
var on = require('sendevent');
on('/eventstream', function(ev) {
console.log(ev);
});
Copyright (c) 2013 Felix Gnass
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