XSockets/Appointment.cs

## Appointment.cs
using System;

namespace XNotify
{
    public class Appointment
    {
        /// <summary>
        /// Id of the appointment
        /// </summary>
        public Guid Id { get; set; }

        /// <summary>
        /// The StorageGuid of the owner (unique for each client, like a session id... kind of)
        /// </summary>
        public Guid StorageGuid { get; set; }

        /// <summary>
        /// The headline for the appointment
        /// </summary>
        public string Subject { get; set; }

        /// <summary>
        /// A little bit more information about the appointment
        /// </summary>
        public string Details { get; set; }

        /// <summary>
        /// The time when the appointment starts
        /// </summary>
        public DateTime Time { get; set; }

        /// <summary>
        /// How many minutes does the meeting last
        /// </summary>
        public int Duration { get; set; }
    }
}

## default.html
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
    <title></title>
    <script src="Scripts/jquery-1.9.1.js"></script>
    <script src="Scripts/XSockets.latest.js"></script>
    <script src="Scripts/knockout-2.3.0.js"></script>
    <!-- For easy convert to .NET datetime //-->
    <script src="Scripts/moment.js"></script>
    <script>
        var conn = undefined;

        //ViewModel
        var VM = {
            Notifications:ko.observableArray()
        };

        $(function () {
            //Activate knockout
            ko.applyBindings(VM);

            //create a connection
            conn = new XSockets.WebSocket('ws://127.0.0.1:4502/Notifier');

            conn.on(XSockets.Events.open, function() {

                //Connection open

                //subscribe to Notify event
                conn.on('notify', function(n) {
                    //Your logic here... Show a notification and play a sound...
                    //I just output it to the viewmodel
                    VM.Notifications.unshift(n);
                });


                //Add a new appointment...
                $('#btn-save-appointment').on('click', function() {

                    //Add a fake that occurs in x minutes where x is the value of our input-timer
                    conn.publish('addappointment', {Subject:'Fake Subject',Details:'Fake Details....',Duration:10, Time:moment().add('minutes',$('#input-timer').val()).format("YYYY-MM-DD HH:mm:ss")});
                });
            });
        });

    </script>
</head>
    <body>
        <label>Minutes from now until the start of the meeting...</label>
        <input id="input-timer" type="number" min="1" max="10" step="1" value="1" /><br/>

        <button id="btn-save-appointment">Add Appointment</button>

        <hr/>
        If you are offline (not on the page) and an notification is sent to you you will still get it as long as you are back within 5 minutes...<br/>
        Read server side code for more info...
        <hr/>
        <div id="notifications" data-bind="foreach:Notifications">
            <div>
                <h4 data-bind="text:Subject"></h4>
                <span data-bind="text:Details"></span>
            </div>
        </div>
    </body>
</html>

## Notifier.cs
using System;
using XSockets.Core.Utility.Storage;
using XSockets.Core.XSocket;
using XSockets.Core.XSocket.Helpers;

namespace XNotify
{
    /// <summary>
    /// A controller (plugin) that will take care of all notificaitons.
    ///
    /// Mission
    /// Users create appointments and should be notified x minutes before the appointment
    ///
    /// Challenges
    /// 1 Keep track of appointments and when they occur
    /// 2 Keep state between connections for all appointments per client
    /// 3 When an reminder fires send the message to the correct client
    /// 4 If the client is offline (maybe between pages) the message should be stored and sent when the client gets back online.
    /// </summary>
    public class Notifier : XSocketController
    {
        public Notifier()
        {
            this.OnClientConnect += Notify_OnClientConnect;
            this.OnClientDisConnect += Notify_OnClientDisConnect;
        }

        void Notify_OnClientDisConnect(object sender, XSockets.Core.Common.Socket.Event.Arguments.OnClientDisConnectArgs e)
        {
            //Tell XSockets to store messages for me while I am offline
            //We store them for 5 minutes and the messages we store is only for the Notify event
            this.OfflineSubscribe(300000,"Notify");
        }

        void Notify_OnClientConnect(object sender, XSockets.Core.Common.Socket.Event.Arguments.OnClientConnectArgs e)
        {
            //Get messages that arrived while I was offline
            this.OnlinePublish();
        }

        /// <summary>
        /// Register a new appointment that will send a notification to the client x minutes before
        /// </summary>
        /// <param name="appointment"></param>
        public void AddAppointment(Appointment appointment)
        {
            //Just add id´s...
            appointment.StorageGuid = this.StorageGuid;
            appointment.Id = Guid.NewGuid();

            //Add to storage so that the NotifierEngine can find it...
            Repository<Guid, Appointment>.AddOrUpdate(appointment.Id, appointment);
        }

        /// <summary>
        /// Send a notification to the client, will be called from the notifierengine...
        /// </summary>
        /// <param name="appointment"></param>
        public void Notify(Appointment appointment)
        {
            //Use a custom extension to also queue messages if the user is offline
            this.SendAndQueue(p => p.StorageGuid == appointment.StorageGuid, appointment, "Notify");
        }
    }
}

## NotifyEngine.cs
using System;
using System.Timers;
using XSockets.Core.Common.Globals;
using XSockets.Core.Common.Socket;
using XSockets.Core.Utility.Storage;
using XSockets.Core.XSocket;
using XSockets.Plugin.Framework.Core;

namespace XNotify
{
    /// <summary>
    /// This is a longrunning contorller in XSockets...
    /// In here we can handle stuff like polling for data or longrunning tasks..
    /// Clients cant connect to this controller....
    /// </summary>
  [XBaseSocketMetadata("NotifyEngine", Constants.GenericTextBufferSize, PluginRange.Internal)]
    public class NotifyEngine : XSocketController
	{
	    private static Notifier notifier;
        private static Timer timer;
        static NotifyEngine()
        {
            //Initialize your long running stuff here
            notifier = new Notifier();

            //Start a timer thar ticks every second...
            timer = new Timer(1000);
            timer.Elapsed += timer_Elapsed;
            timer.Start();
        }

        /// <summary>
        /// On tick we check if there are any appointments that needs to be sent...
        /// We will send a notification 10 seconds before the meeting.. Hurry up  ;)
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        static void timer_Elapsed(object sender, ElapsedEventArgs e)
        {
            var appointments = Repository<Guid, Appointment>.Find(p => p.Time.AddSeconds(-10) <= DateTime.Now);
            foreach (var appointment in appointments)
            {
                //Notify client
                notifier.Notify(appointment);
                //Remove appointment
                Repository<Guid, Appointment>.Remove(appointment.Id);
            }
        }
    }
}

## XSocketsHelper.cs
using System;
using XSockets.Core.Common.Socket;
using XSockets.Core.XSocket;
using XSockets.Core.XSocket.Helpers;

namespace XNotify
{
    /// <summary>
    /// Custom extension for this sample
    /// </summary>
    public static class XSocketsHelper
    {
        /// <summary>
        /// A helper for both sending to those online and storing for those offline...
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="socket"></param>
        /// <param name="condition"></param>
        /// <param name="o"></param>
        /// <param name="eventname"></param>
        public static void SendAndQueue<T>(this T socket, Func<T, bool> condition, object o, string eventname)
            where T : XBaseSocket, IXBaseSocket
        {
            //Send to onliners
            socket.SendTo(condition, o, eventname);
            //Queue message for offliners
            socket.Queue(socket.ToTextArgs(o,eventname), condition);
        }
    }
}
	using System;

	namespace XNotify
	{
	public class Appointment
	{
	/// <summary>
	/// Id of the appointment
	/// </summary>
	public Guid Id { get; set; }

	/// <summary>
	/// The StorageGuid of the owner (unique for each client, like a session id... kind of)
	/// </summary>
	public Guid StorageGuid { get; set; }

	/// <summary>
	/// The headline for the appointment
	/// </summary>
	public string Subject { get; set; }

	/// <summary>
	/// A little bit more information about the appointment
	/// </summary>
	public string Details { get; set; }

	/// <summary>
	/// The time when the appointment starts
	/// </summary>
	public DateTime Time { get; set; }

	/// <summary>
	/// How many minutes does the meeting last
	/// </summary>
	public int Duration { get; set; }
	}
	}
	<!DOCTYPE html>
	<html xmlns="http://www.w3.org/1999/xhtml">
	<head>
	<title></title>
	<script src="Scripts/jquery-1.9.1.js"></script>
	<script src="Scripts/XSockets.latest.js"></script>
	<script src="Scripts/knockout-2.3.0.js"></script>
	<!-- For easy convert to .NET datetime //-->
	<script src="Scripts/moment.js"></script>
	<script>
	var conn = undefined;

	//ViewModel
	var VM = {
	Notifications:ko.observableArray()
	};

	$(function () {
	//Activate knockout
	ko.applyBindings(VM);

	//create a connection
	conn = new XSockets.WebSocket('ws://127.0.0.1:4502/Notifier');

	conn.on(XSockets.Events.open, function() {

	//Connection open

	//subscribe to Notify event
	conn.on('notify', function(n) {
	//Your logic here... Show a notification and play a sound...
	//I just output it to the viewmodel
	VM.Notifications.unshift(n);
	});


	//Add a new appointment...
	$('#btn-save-appointment').on('click', function() {

	//Add a fake that occurs in x minutes where x is the value of our input-timer
	conn.publish('addappointment', {Subject:'Fake Subject',Details:'Fake Details....',Duration:10, Time:moment().add('minutes',$('#input-timer').val()).format("YYYY-MM-DD HH:mm:ss")});
	});
	});
	});

	</script>
	</head>
	<body>
	<label>Minutes from now until the start of the meeting...</label>
	<input id="input-timer" type="number" min="1" max="10" step="1" value="1" /><br/>

	<button id="btn-save-appointment">Add Appointment</button>

	<hr/>
	If you are offline (not on the page) and an notification is sent to you you will still get it as long as you are back within 5 minutes...<br/>
	Read server side code for more info...
	<hr/>
	<div id="notifications" data-bind="foreach:Notifications">
	<div>
	<h4 data-bind="text:Subject"></h4>
	<span data-bind="text:Details"></span>
	</div>
	</div>
	</body>
	</html>
	using System;
	using XSockets.Core.Utility.Storage;
	using XSockets.Core.XSocket;
	using XSockets.Core.XSocket.Helpers;

	namespace XNotify
	{
	/// <summary>
	/// A controller (plugin) that will take care of all notificaitons.
	///
	/// Mission
	/// Users create appointments and should be notified x minutes before the appointment
	///
	/// Challenges
	/// 1 Keep track of appointments and when they occur
	/// 2 Keep state between connections for all appointments per client
	/// 3 When an reminder fires send the message to the correct client
	/// 4 If the client is offline (maybe between pages) the message should be stored and sent when the client gets back online.
	/// </summary>
	public class Notifier : XSocketController
	{
	public Notifier()
	{
	this.OnClientConnect += Notify_OnClientConnect;
	this.OnClientDisConnect += Notify_OnClientDisConnect;
	}

	void Notify_OnClientDisConnect(object sender, XSockets.Core.Common.Socket.Event.Arguments.OnClientDisConnectArgs e)
	{
	//Tell XSockets to store messages for me while I am offline
	//We store them for 5 minutes and the messages we store is only for the Notify event
	this.OfflineSubscribe(300000,"Notify");
	}

	void Notify_OnClientConnect(object sender, XSockets.Core.Common.Socket.Event.Arguments.OnClientConnectArgs e)
	{
	//Get messages that arrived while I was offline
	this.OnlinePublish();
	}

	/// <summary>
	/// Register a new appointment that will send a notification to the client x minutes before
	/// </summary>
	/// <param name="appointment"></param>
	public void AddAppointment(Appointment appointment)
	{
	//Just add id´s...
	appointment.StorageGuid = this.StorageGuid;
	appointment.Id = Guid.NewGuid();

	//Add to storage so that the NotifierEngine can find it...
	Repository<Guid, Appointment>.AddOrUpdate(appointment.Id, appointment);
	}

	/// <summary>
	/// Send a notification to the client, will be called from the notifierengine...
	/// </summary>
	/// <param name="appointment"></param>
	public void Notify(Appointment appointment)
	{
	//Use a custom extension to also queue messages if the user is offline
	this.SendAndQueue(p => p.StorageGuid == appointment.StorageGuid, appointment, "Notify");
	}
	}
	}
	using System;
	using System.Timers;
	using XSockets.Core.Common.Globals;
	using XSockets.Core.Common.Socket;
	using XSockets.Core.Utility.Storage;
	using XSockets.Core.XSocket;
	using XSockets.Plugin.Framework.Core;

	namespace XNotify
	{
	/// <summary>
	/// This is a longrunning contorller in XSockets...
	/// In here we can handle stuff like polling for data or longrunning tasks..
	/// Clients cant connect to this controller....
	/// </summary>
	[XBaseSocketMetadata("NotifyEngine", Constants.GenericTextBufferSize, PluginRange.Internal)]
	public class NotifyEngine : XSocketController
	{
	private static Notifier notifier;
	private static Timer timer;
	static NotifyEngine()
	{
	//Initialize your long running stuff here
	notifier = new Notifier();

	//Start a timer thar ticks every second...
	timer = new Timer(1000);
	timer.Elapsed += timer_Elapsed;
	timer.Start();
	}

	/// <summary>
	/// On tick we check if there are any appointments that needs to be sent...
	/// We will send a notification 10 seconds before the meeting.. Hurry up ;)
	/// </summary>
	/// <param name="sender"></param>
	/// <param name="e"></param>
	static void timer_Elapsed(object sender, ElapsedEventArgs e)
	{
	var appointments = Repository<Guid, Appointment>.Find(p => p.Time.AddSeconds(-10) <= DateTime.Now);
	foreach (var appointment in appointments)
	{
	//Notify client
	notifier.Notify(appointment);
	//Remove appointment
	Repository<Guid, Appointment>.Remove(appointment.Id);
	}
	}
	}
	}