nodejs-sse

server sent event

Usage no npm install needed!

<script type="module">
  import nodejsSse from 'https://cdn.skypack.dev/nodejs-sse';
</script>

README

nodejs-sse

Install

$ npm install nodejs-sse

How to use

Use with express:

var SSE = require('sse-nodejs');

var express = require('express');

var app = express();

app.get('/', (req,res) => {
   res.sendFile(__dirname+ '/index.html');
});

app.get('/time', async(req,res) => {
    var app = SSE(res);

    app.sendEvent('time', function () {
    
        const data = await getData()        
        return data
    },1000);

    app.disconnect( () => {
        console.log("disconnected");
    });

    app.removeEvent('time',3100);

});

app.listen(3000,  () => {
    console.log('Simple SSE server start at port: 3000')
});

Use in frontend

<!DOCTYPE html>
<html>
<head></head>
<body>
HELLO WORLD
<div id="clock"></div>
</body>
<script>
    var ev = new EventSource('/time');
    ev.addEventListener('time', function (result) {
        document.getElementById("clock").innerHTML += '<h4>' + result.data + '</h4>'
    })
</script>
</html>

Option

    var app = sse(res, options);
Option Desciption
padding add padding 2Kb, default true
heartbeat send a "heartbeat" every 10 seconds. https://bugzilla.mozilla.org/show_bug.cgi?id=444328
retry time to retry, default time 3000
headers add extra header, default header {"Content-Type": "text/event-stream","Cache-Control": "no-cache", "Connection": "keep-alive"}

Function

Function Desciption
send(data) send data only (message on server sent events)
sendEvent(name,data,timeInterval) send data after timeInterval if no timeInterval send once (data can be a function)
removeEvent(nameEvent, timeout) remove an event after timeout, if no timeout it will remove immediately
disconnect(function) listen event 'close'

How to use

You can use this module with HTTP response object

The MIT License (MIT)

Copyright (c) <2020> Jaon Micle