I am new to node.js and socket.io and I am trying to write a small server that will update a webpage based on python output.
Eventually this will be used for a temperature sensor so for now I have a dummy script which prints temperature values every few seconds:
Thermostat.py
import random, time
for x in range(10):print(str(random.randint(23,28))+" C")time.sleep(random.uniform(0.4,5))
Here's a cut down version of the server:
Index.js
var sys = require('sys'), spawn = require('child_process').spawn, thermostat = spawn('python', ["thermostat.py"]),app = require('express')(),http = require('http').Server(app),io = require('socket.io')(http);thermostat.stdout.on('data', function (output) { var temp = String(output);console.log(temp);io.sockets.emit('temp-update', { data: temp});
}); app.get('/', function(req, res){res.sendFile(__dirname + '/index.html');});
And finally the web page:
Index.html
<!doctype html>
<html><head><title>Live temperature</title><link rel="stylesheet" type="text/css" href="styles.css"></head><body><div id="liveTemp">Loading...</div><script src="http://code.jquery.com/jquery-1.11.1.js"></script><script src="/socket.io/socket.io.js"></script><script>var socket = io();socket.on('temp-update', function (msg) {$('#liveTemp').html(msg.data)});</script></body>
</html>
The problem is nodejs seems to recieve all of the temperature values at once, and instead of getting 10 temperature values at random intervals, I get all of the values in one long string after the script has finished:
