node.js - Observable calls function multiple times with single change -


i writing application reading value , doing calculations on interval. if value changes modifies observable calls function emit sendval. application works great 1 user, problem when multiple users connect , value changes each user receives same notification multiple times (the same number of notifications concurrent users).

i think using observable incorrectly, can't figure out why i'm getting multiple messages single change.

server code:

var app = require('express')(); var http = require('http').server(app); var io = require('socket.io')(http); var o = require('observable');      var reportedtotal = o(0);  app.all('/', function (req, res, next) {     res.header("access-control-allow-origin", "*");     res.header("access-control-allow-headers", "x-requested-with");     next(); });      io.on('connection', function (socket) {     console.log('connected');     reportedtotal(function(val) {         io.emit('sendval', json.stringify({ lvl: val }));     });             socket.on('disconnect', function() {         console.log('disconnected');     }); });  http.listen(3000, function () {     console.log('listening on *:3000'); });  setinterval(function () {     var tot = 0;     //does stuff here     if(changed) { reportedtotal(tot); } }, 1000);

client code:

var url = <server ip>; var socket = io(url); socket.on('sendval', function(msg){     $('#messages').append($('<li>').text(msg)); });


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