Question

I’m trying to optimize the push notifications on my server. For now I send those one by one (with an old library) and it takes a while (4 hours).

I refactored my service to send a notification with a lot of device tokens (For now I tried with batches of 500 tokens). For that I’m using the Redth/PushSharp library. I followed the sample code then I adapted it to send the notifications to severals device tokens.

PushService service = new PushService();

//Wire up the events
service.Events.OnDeviceSubscriptionExpired += new PushSharp.Common.ChannelEvents.DeviceSubscriptionExpired(Events_OnDeviceSubscriptionExpired);
service.Events.OnDeviceSubscriptionIdChanged += new PushSharp.Common.ChannelEvents.DeviceSubscriptionIdChanged(Events_OnDeviceSubscriptionIdChanged);
service.Events.OnChannelException += new PushSharp.Common.ChannelEvents.ChannelExceptionDelegate(Events_OnChannelException);
service.Events.OnNotificationSendFailure += new PushSharp.Common.ChannelEvents.NotificationSendFailureDelegate(Events_OnNotificationSendFailure);
service.Events.OnNotificationSent += new PushSharp.Common.ChannelEvents.NotificationSentDelegate(Events_OnNotificationSent);
service.Events.OnChannelCreated += new PushSharp.Common.ChannelEvents.ChannelCreatedDelegate(Events_OnChannelCreated);
service.Events.OnChannelDestroyed += new PushSharp.Common.ChannelEvents.ChannelDestroyedDelegate(Events_OnChannelDestroyed);

//Configure and start ApplePushNotificationService
string p12Filename = ...
string p12FilePassword = ...

var appleCert = File.ReadAllBytes(p12Filename);

service.StartApplePushService(new ApplePushChannelSettings(true, appleCert, p12FilePassword));

var appleNotification = NotificationFactory.Apple();

foreach (var itemToProcess in itemsToProcess)
{
    itemToProcess.NotificationDateTime = DateTime.Now;
    mobile.SubmitChanges();

    string deviceToken = GetCleanDeviceToken(itemToProcess.MobileDevice.PushNotificationIdentifier);
    appleNotification.ForDeviceToken(deviceToken);
}

service.QueueNotification(appleNotification
    .WithAlert(itemsToProcess[0].MobileDeviceNotificationText.Text)
    .WithSound("default")
    .WithBadge(0)
    .WithCustomItem("View", itemsToProcess[0].Value.ToString()));

//Stop and wait for the queues to drains
service.StopAllServices(true);

Then I tried to send 3 notifications to 2 devices. Only the first device got them (and the problem is not device-related because I tried with both of them separately).
Right after that an OperationCanceledException is thrown in the PushChannelBase class. So I don’t know what’s wrong. Any idea?

Answer 1

You should queue a separate notification for each item to process.
It is not possible set multiple device tokens on a single notification. The OperationCanceledException will occur, because you do.