Node Knockout Demo Application

config.js

/**
 * Enter your configuration details in this file.
 */

// Details of your CouchDB instance.
exports.couchdb  = {
	userid : '',
	password : '',
	host : 'http://127.0.0.1',
	port : '5984',
	dbname : ''
};

// Your SMSified credentials - free signup at https://smsified.com/signup
exports.smsified = {
		username : '',
		password : '',
		senderAddress : ''
};

couch-watcher.js

/**
 * Node.js class that watches the CouchDB _changes API and emits events on new changes.
 */
var EventEmitter = require('events').EventEmitter;
var cradle = require('cradle');

CouchWatcher = function(options) {
	this.userid = options.userid;
	this.password = options.password;
	this.dbname = options.dbname;
	this.host = options.host || '127.0.0.1';
	this.port = options.port || 5984;
	this.heartbeat = options.heartbeat || 1000;
};

CouchWatcher.prototype = new EventEmitter;

CouchWatcher.prototype.watch = function(filter, since) {
	
	var self = this;
	
	// Create new connection to CouchDB instance.
	var db = new (cradle.Connection)(self.host, self.port, 
			{
				auth : {
					username : self.userid,
					password : self.password
				}
			}).database(self.dbname);

	// Watch changes API and emit event with document.
	var options = { include_docs : true, feed : 'continuous', heartbeat : self.heartbeat};
	if(filter) {
		options.filter = filter;
	}
	if(since) {
		options.since = since;
	}
	db.changes(options).on('response', function(res) {
		res.on('data', function(change) {
			self.emit('doc', change.doc);
		});
		res.on('end', function() {
			self.emit('end');
		});
	});

};

exports.CouchWatcher = CouchWatcher;

filter.json

/**
 * JSON for a CouchDB filter called "newdoc"
 *  more on CouchDB _changes API and filters at http://guide.couchdb.org/editions/1/en/notifications.html#filters
 */
{
   "newdoc": "function(doc, req) { if(doc._rev.charAt(0) == '1') { return true; } return false;}"
}

sms-app.js

/**
 *  A simple SMSified app built with Node.js and CouchDB.
 */
var http = require('http');
var sys = require('sys');
var config = require('./config');
var CouchWatcher = require('./couch-watcher').CouchWatcher;
var smsified = require('smsified');
var cradle = require('cradle');

// Function to save / update a doc in CouchDB.
function saveDoc(doc) {
	db.save(doc, function(err, res) {
		if (err) {
			sys.puts('Could not save document.');
		} else {
			sys.puts('Document saved: ' + res.id);
		}
	});
}

// CouchDB changes watcher.
var responder = new CouchWatcher(config.couchdb);
responder.watch('app/newdoc');

// Event handler for doc delivered from CouchDB changes API.
responder.addListener('doc', function(doc) {
	var sms = new SMSified(config.smsified.username, config.smsified.password);
	
	// The reply to be sent to incoming SMS messages. This can be whatever you want, based on app logic or business rules.
	var reply = 'Node.js rocks!!';
	
	var options = {senderAddress: config.smsified.senderAddress, address: doc.senderAddress, message: reply};
	sms.sendMessage(options, function(result) {
		doc.reply = reply;
		doc.sendResult = result;
		saveDoc(doc); 
	});

});

// Port the web server will run on.
var port = process.argv[2] || 8000;

// Connection to CouchDB for saving docs.
var db = new (cradle.Connection)(config.couchdb.host, config.couchdb.port, {
	auth : {
		username : config.couchdb.userid,
		password : config.couchdb.password
	}
}).database(config.couchdb.dbname);

// Web server to listen for incoming HTTP POSTs from SMSified.
var server = http.createServer(function(req, res) {
	req.addListener('data', function(data) {
      	var inbound = new InboundMessage(JSON.parse(data));
      	saveDoc(inbound); 
	});
	res.writeHead(200);
	res.end();

}).listen(port);