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WNS PushNotificationReceived does not intercept toast push notification

I'm writing a windows desktop app that relies on notifications to work. However, the event handler code, PushNotificationReceived on the channel does not seem to actually fire when I receive a notification. The following code is called to get the channel before its uri is sent to my server:
internal async Task<PushNotificationChannel> GetChannel()
{
PushNotificationChannel pnc;
try
{
pnc = await PushNotificationChannelManager.CreatePushNotificationChannelForApplicationAsync();
if (_channel == null || !pnc.Uri.Equals(_channel.Uri))
{
_channel = pnc;
_channel.PushNotificationReceived += OnPushNotificationReceived;
Debug.WriteLine(_channel.Uri);
}
}
catch (Exception ex)
{
Debug.WriteLine(ex.Message);
_channel = null;
}
dispatcher = Windows.UI.Core.CoreWindow.GetForCurrentThread().Dispatcher;
return _channel;
}
Such that anytime the channel is created or updated (via a different channel uri), it should assign the new channel's PushNotificationReceived event to the following (which is basically lifted from msdn's example):
void OnPushNotificationReceived(PushNotificationChannel sender, PushNotificationReceivedEventArgs e)
{
string typeString = String.Empty;
string notificationContent = String.Empty;
switch (e.NotificationType)
{
//
//other notification types omitted for brevity
//
case PushNotificationType.Toast:
notificationContent = e.ToastNotification.Content.GetXml();
typeString = "Toast";
// Setting the cancel property prevents the notification from being delivered. It's especially important to do this for toasts:
// if your application is already on the screen, there's no need to display a toast from push notifications.
e.Cancel = true;
break;
}
Debug.WriteLine("Received notification, with payload: {0}", notificationContent);
string text = "Received a " + typeString + " notification, containing: " + notificationContent;
var ignored = dispatcher.RunAsync(CoreDispatcherPriority.Normal, () =>
{
MainPage.Current.ClearBanner();
});
}
Importantly, "MainPage.Current" is a reference to the app's main page as a static variable. The clear banner line simply removes a pink banner from the main page (just trying to get something simple working to start).
However, the code never seems to fire (no debug statement, pink banner remains). I am successfully getting the toast notification, and clicking on it will set focus to my app, so it's definitely not going to the wrong place.
Is there something I am doing wrong or some way to debug the notifications themselves?

Asterisk ARI conference call app: authorize / ask for pin number

I'm using a C#/.NET library to implement the Asterisk RESTful Interface (ARI) to create conference call app.
So far the app works like this:
User calls the number
App answers
App starts voice detection
App asks for name and records the audio
App adds the user to the conference
Requirement:
I need to add in the above process some kind of authorization, before the user is added into the conference. I need to implement the ask for a PIN number functionality, create a PIN number construct and if the caller enters the correct PIN add the caller to the correct conference call.
The Code:
Conference:
public Conference( AriClient c, Guid id, string name)
{
_client = c;
Id = id;
ConferenceName = name;
State = ConferenceState.Destroyed;
c.OnChannelDtmfReceivedEvent += c_OnChannelDtmfReceivedEvent; // ??
c.OnBridgeCreatedEvent += c_OnBridgeCreatedEvent;
c.OnChannelEnteredBridgeEvent += c_OnChannelEnteredBridgeEvent;
c.OnBridgeDestroyedEvent += c_OnBridgeDestroyedEvent;
c.OnChannelLeftBridgeEvent += c_OnChannelLeftBridgeEvent;
c.OnRecordingFinishedEvent += c_OnRecordingFinishedEvent;
// Added support for talk detection
c.OnChannelTalkingStartedEvent += c_OnChannelTalkingStartedEvent;
c.OnChannelTalkingFinishedEvent += c_OnChannelTalkingFinishedEvent;
Debug.Print("Added Conference {0}", ConferenceName);
}
OnChannelEnteredBridgeEvent:
private void c_OnChannelEnteredBridgeEvent(object sender, ChannelEnteredBridgeEvent e)
{
ConferenceUser confUser = ConferenceUsers.SingleOrDefault(x => x.Channel.Id == e.Channel.Id);
if (confUser == null) return;
confUser.State = ConferenceUserState.InConf;
if (ConferenceUsers.Count(x => x.State == ConferenceUserState.InConf) > 1) // are we the only ones here
{
// stop moh
_client.Bridges.StopMoh(Confbridge.Id);
// change state
State = ConferenceState.Ready;
// announce new user
_client.Bridges.Play(Confbridge.Id, "recording:" + confUser.CurrentRecodingId, "en", 0, 0, Guid.NewGuid().ToString());
_client.Bridges.Play(Confbridge.Id, "sound:conf-hasjoin", "en", 0, 0, Guid.NewGuid().ToString());
}
else
{
// only caller in conf
_client.Channels.Play(e.Channel.Id, "sound:conf-onlyperson", "en", 0, 0, Guid.NewGuid().ToString());
}
}
StartConference:
public bool StartConference()
{
// Create the conference bridge
Debug.Print("Requesting new bridge {0} for {1}", Id, ConferenceName);
Bridge bridge = _client.Bridges.Create("mixing", Id.ToString(), ConferenceName);
if (bridge == null)
{
return false;
}
Debug.Print("Subscribing to events on bridge {0} for {1}", Id, ConferenceName);
_client.Applications.Subscribe(AppConfig.AppName, "bridge:" + bridge.Id);
// Start MOH on conf bridge
_client.Bridges.StartMoh(bridge.Id, "default");
// Default state is ReadyWaiting until MOH is turned off
State = ConferenceState.ReadyWaiting;
Confbridge = bridge;
// Conference ready to accept calls
State = ConferenceState.Ready;
return true;
}
AddUser:
public bool AddUser(Channel c) //here check for pin and caller id
{
if (State == ConferenceState.Destroying)
return false;
if (State == ConferenceState.Destroyed)
{
// We should initiate a new conference bridge
if (!StartConference())
return false;
}
if (State < ConferenceState.Ready) return false;
// Answer channel
_client.Channels.Answer(c.Id);
// Turn on talk detection on this channel
_client.Channels.SetChannelVar(c.Id, "TALK_DETECT(set)", "");
// Add conference user to collection
ConferenceUsers.Add(new ConferenceUser(this, c, _client, ConferenceUserType.Normal));
return true;
}
Question:
How can I raise/invoke the "ask for pin number" event/channel within the app and grab the input DTMF digits into a variable?
Can this be done solely in my C# ARI application, or do I need to fiddle with the .conf files on the Asterisk server?
My preferred way of doing is is by implementing it in my C# ARI app, as this would give me more control over conferences.

You should create some dialplan to support that and ask dialplan check you pin etc
Sure it can be done without dialplan support, but in that case task become guru level, have no real sense do like that.
For start i can recommend you "Asterisk the future of telephony" book.
You can use func_odbc, Read application, CHANNEL function(for ip)

Misbehaving Service behviors

Basically I'm making a program to simulate a petrol station system.
My problem is that I'm trying to send a request through a WCF service such as this:
User Requests Pump to be activated ----> WCF SERVICE ----> Point of Sale
User starts pumping petrol<---- WCF SERVICE <---- Point of Sale Accepts
At the moment it works, but only sometimes.
This is how I try to get a response:
while(PumpserviceClient.getRequestedAcceptedStatusFromPos().Accepted == false)
{
PumpserviceClient.RequestPump(int.Parse(PumpID));
// needs to wait for pump to be activated
if (PumpserviceClient.getRequestedAcceptedStatusFromPos().Accepted == true /*&& PumpserviceClient.getRequestedAcceptedStatusFromPos().PumpNo == int.Parse(PumpID)*/)
{
MessageBox.Show(" The Pos has accepted your pump request");
// if its accepted you call
Customer.ActivatePump();
}
And these are the methods in the service:
bool Accepted= false;
bool Requested=false;
public void AcceptPump(int PumpNumber)
{
Accepted = true;
Requested = false;
int pumpnumber = PumpNumber;
PumpRequest.Accepted = Accepted;
PumpRequest.Requested = Requested;
}
public void RequestPump(int PumpNumber)
{
int pumpnumber = PumpNumber;
Requested = true;
Accepted = false;
PumpRequest.Accepted = Accepted;
PumpRequest.PumpNo = PumpNumber;
PumpRequest.Requested = Requested;
}
public void ResetRequest(int PumpNumber)
{
int pumpnumber = PumpNumber;
Requested = false;
Accepted = false;
PumpRequest.Accepted = Accepted;
PumpRequest.PumpNo = 0;
PumpRequest.Requested = Requested;
}
public Message getRequestedStatusFromPump()
{
return PumpRequest;
}
public Message getRequestedAcceptedStatusFromPos()
{
return PumpRequest;
}
}
and the point of sale system accepts the requests by:
if (Client.getRequestedStatusFromPump().Requested == true)
{
MessageBox.Show("Pump Number: "+Client.getRequestedStatusFromPump().PumpNo + " Is waiting to be accepted");
// need to press a button or something
Client.AcceptPump(Client.getRequestedStatusFromPump().PumpNo);
}
Code here http://www.pastebucket.com/8642

I read the code posted. You use the following attribute:
[ServiceBehavior(InstanceContextMode = InstanceContextMode.Single)]
This means your code will not multi-thread. But there is no guarantee multiple sessions won't make requests and "interrupt" each other's workflow.
For example:
Client A calls request pump
Client B calls reset pump
Client A reads... client A wonders why pump was reset.
Your code is written expecting the object to be by session. I'd suggest using this context mode and seeing if you have better luck.
The other option is to add session information to your model. I can't imagine why this would be useful. It certainly won't be easy.

The only way i found around this problem, without changing service behaviors was to create a new list
public void CreatePumpList()
{
WaitingPumps = new List<WaitingPumps>();
for (int i = 0; i < PumpLimit+1 ; i++)
{
WaitingPumps.Add(new WaitingPumps());
}
}
Then just use the pump Number as the index in this list so they don't get confused with each other.

Using Web API for a Windows Service to Receive Commands and Perform Tasks via Polling?

I have a project where I need to create a windows service that, when instructed via a command, will perform various tasks. This server would run on multiple servers and would effectively perform the same kind of tasks when requested.
For example, I would like to have a Web API service that listens for requests from the servers.
The service running on the server would send a query to Web API every 25 secs or so and pass to it its SERVERNAME. The Web API logic will then look up the SERVERNAME and look for any status updates for various tasks... I.E., if a status for a DELETE command is a 1, the service would delete the folder containing log files... if a status for a ZIP command is a 1, the service would zip the folder containing log files and FTP them to a centralized location.
This concept seems simple enough, and I think I need a nudge to tell me if this sounds like a good design. I'm thinking of using .NET 4.5 for the Windows Service, so that I can use the HttpClient object and, of course, .NET 4.5 for the Web API/MVC project.
Can someone please get me started on what a basic Web API woudld look like provide status updates to the Windows services that are running and issue commands to them...
I'm thinking of having a simple MVC website that folks will have a list of servers (maybe based on a simple XML file or something) that they can click various radio buttons to turn on "DELETE", "ZIP" or whatever, to trigger the task on the service.

I do something similar. I have a main Web API (a Windows Service) that drives my application and has a resource called /Heartbeat.
I also have a second Windows Service that has a timer fire every 30 seconds. Each time the timer fires it calls POST /heartbeat. When the heartbeat request is handled, it goes looking for tasks that have been scheduled.
The advantage of this approach is that the service makes the hearbeat request is extremely simple and never has to be updated. All the logic relating to what happens on a heartbeat is in the main service.
The guts of the service are this. It's old code so it is still using HttpWebRequest instead of HttpClient, but that's trivial to change.
public partial class HeartbeatService : ServiceBase {
readonly Timer _Timer = new System.Timers.Timer();
private string _heartbeatTarget;
public HeartbeatService() {
Trace.TraceInformation("Initializing Heartbeat Service");
InitializeComponent();
this.ServiceName = "TavisHeartbeat";
}
protected override void OnStart(string[] args) {
Trace.TraceInformation("Starting...");
_Timer.Enabled = true;
_Timer.Interval = Properties.Settings.Default.IntervalMinutes * 1000 * 60;
_Timer.Elapsed += new ElapsedEventHandler(_Timer_Elapsed);
_heartbeatTarget = Properties.Settings.Default.TargetUrl;
}
protected override void OnStop() {
_Timer.Enabled = false;
}
private void _Timer_Elapsed(object sender, ElapsedEventArgs e) {
Trace.TraceInformation("Heartbeat event triggered");
try {
var httpWebRequest = (HttpWebRequest)HttpWebRequest.Create(_heartbeatTarget);
httpWebRequest.ContentLength = 0;
httpWebRequest.Method = "POST";
var response = (HttpWebResponse)httpWebRequest.GetResponse();
Trace.TraceInformation("Http Response : " + response.StatusCode + " " + response.StatusDescription);
} catch (Exception ex) {
string errorMessage = ex.Message;
while (ex.InnerException != null) {
errorMessage = errorMessage + Environment.NewLine + ex.InnerException.Message;
ex = ex.InnerException;
}
Trace.TraceError(errorMessage);
}
}
}

You can do it with ServiceController.ExecuteCommand() method from .NET.
With the method you can sand custom command to windows' service.
Then in your service you need to implement ServiceBase.OnCustomCommand() to serve incomming custom command event in service.
const int SmartRestart = 8;
...
//APPLICATION TO SEND COMMAND
service.ExecuteCommand(SmartRestart);
...
//SERVICE
protected override void OnCustomCommand(int command)
{
if (command == SmartRestart)
{
// ...
}
}

SignalR notification system

This is my first time playing around with SignalR. I am trying to build a notification system where the server checks at regular intervals to see if there is something (query database) to broadcast and if there is then it broadcasts it to all the clients.
I came across this post on Stackoverflow and was wondering if modifying the code to make a DB call at a particular interval was indeed the right way to do it. If not is there a better way to do it?
I did see a lot of Notification related questions posted here but none with any code in it. Hence this post.
This is the exact code that I am using:
public class NotificationHub : Hub
{
public void Start()
{
Thread thread = new Thread(Notify);
thread.Start();
}
public void Notify()
{
List<CDCNotification> notifications = new List<CDCNotification>();
while (true)
{
notifications.Clear();
notifications.Add(new CDCNotification()
{
Server = "Server A", Application = "Some App",
Message = "This is a long ass message and amesaadfasd asdf message",
ImgURL = "../Content/Images/accept-icon.png"
});
Clients.shownotification(notifications);
Thread.Sleep(20000);
}
}
}
I am already seeing some weird behaviour where the notifications come more often than they are supposed to. Even though I am supposed to get it every 20s I get it around 4-5 secs and I get multiple messages.
Here is my client:
var notifier = $.connection.notificationHub;
notifier.shownotification = function (data) {
$.each(data, function (i, sample) {
var output = Mustache.render("<img class='pull-left' src='{{ImgURL}}'/> <div><strong>{{Application}}</strong></div><em>{{Server}}</em> <p>{{Message}}</p>", sample);
$.sticky(output);
});
};
$.connection.hub.start(function () { notifier.start(); });

Couple of notes:
As soon as a second client connects to your server there will be 2 threads sending the notifications, therefore if you ave more than one client you will have intervals smaller than 20s
Handling thread manually within ASP.NET is considered bad practice, you should avoid this if possible
In general this smells a lot like polling which is kind of the thing SignalR lets you get rid of since you don't need to signal the server/client
In order to solve this you need todo something like this (again, threads in a web application are generally not a good idea):
public class NotificationHub : Hub
{
public static bool initialized = false;
public static object initLock = new object();
public void Start()
{
if(initialized)
return;
lock(initLock)
{
if(initialized)
return;
Thread thread = new Thread(Notify);
thread.Start();
initialized = true;
}
}
public void Notify()
{
List<CDCNotification> notifications = new List<CDCNotification>();
while (true)
{
notifications.Clear();
notifications.Add(new CDCNotification() { Server = "Server A", Application = "Some App", Message = "This is a long ass message and amesaadfasd asdf message", ImgURL = "../Content/Images/accept-icon.png" });
Clients.shownotification(notifications);
Thread.Sleep(20000);
}
}
}
The static initialized flag prevents multiple threads from being created. The locking around it is to ensure that the flag is only set once.

I am working on the same task over here. Instead of continuously checking the database, I created my own events and listener, where an event is RAISED when a NOTIFICATION IS ADDED :) What do you think about that?