Simple program combining temperature sensor and led through GPIO.

tooHotLed.js

#!/usr/bin/env node
var fs = require('fs');
var gpio = require("gpio");

var gpio10 = gpio.export(10, {
	direction: "out",
	ready: function() {
		function readTemperature() {
			var data = fs.readFileSync('/sys/bus/w1/devices/28-0000047c275a/w1_slave', { encoding: 'ascii' });
			var temperature;

			data = data.split(' ');

			temperature = parseFloat(data[data.length-1].split('=')[1]) / 1000.0;
			temperature = Math.round(temperature * 10) / 10;

			return temperature;
		}

		setInterval(function() {
			var temperature = readTemperature();
			if (temperature > 30) {
				gpio10.set();
			}
			else {
				gpio10.set(0);
			}
			console.log(temperature);
		}, 500);

		process.on('SIGINT', function() {
			gpio10.set(0);
			gpio10.unexport();
			process.exit(0);
		});
	}
});