On the pricing page for Azure Notification Hubs:
https://azure.microsoft.com/en-us/pricing/details/notification-hubs/
It states that "Standard namespaces have access to Per Message Telemetry and Push Notification Services Feedback". I am using a Standard namespace.
The app is sending template based notifications to an iOS app from my back end using the C# Notification Hub client. For example:
NotificationOutcome result = await hub.SendTemplateNotificationAsync(params, tags);
The result.State is coming back as Enqueued, but some notifications are not being delivered and I am trying to figure out why. (There are no bad registrations in the hub - I have already checked that.)
In the Azure portal, I can see aggregate metrics of messages received by the hub, errors, etc. - but I cannot seem to view the specific results of a push message to determine why it failed to reach the device, or even if it was successfully handed off to APNS.
How can I see the results of an attempted push? Is this even possible with Azure Notification Hubs?
Did you try Fiddler+https://msdn.microsoft.com/en-us/library/azure/mt608135.aspx ?
Also, as far as i know, Apple does not guarantee the delivery of all notifications.
1) Is Apple's push notification service reliable?
More of that,
2) https://azure.microsoft.com/en-us/documentation/articles/notification-hubs-faq/
"A PNS does not guarantee any SLA for delivering notifications; however, typically a vast majority of push notifications are delivered to target devices within a few minutes (usually within the limits of 10 minutes) from the time they are sent to our platform. "
Related
For a few weeks there is an issue with Azure Notification Hub - we have a backend service that registers devices & schedules notifications. When one of the notifications is triggered, then we send it to Azure based on the device type (create the payload and all of that).
The response we get from azure is positive, the notification has been enqueued and is ready to be sent. However, it seems that Azure does not send them all. No error is thrown but only a small percentage is sent. It also does not seem to depend on the device type.
There are no logs to read - or none tha I can find and I cannot pin point the issue.
We have an endpoint that triggers the sending of a notification - we did a test run with 30 notifications (similar and different payloads for the same device) and it all went well.
Not sure how to troubleshoot this or what might cause this. I understood from the documentation that the device might be inactive and then the notification is deleted from the queue after a while. But it seems that the said device receives 1 out of 3 notifications (sent at the same time).
Any feedback would be appreciated.
Edit update:
After upgrading to the Standard plan, we managed to get some more information and it looks like Azure gives back a "Success" with a count of "1" but the device does not receive the notification - the problem is, this happens randomly. It's not always the same device that does or does not receive the notification.
Sorry this isn't a super helpful answer, but could you please open a support ticket in the Azure Portal for us to investigate your particular case? This does not seem like expected behavior so the team will have to look into the logs for your namespace and hub.
One immediate thought - there is de-duplication logic when sending notifications. So within a period of time (something like 15 minutes) if the same notification payload is being sent to the same device, Notification Hubs will automatically drop that duplicate notification.
I need the Notification Message Id that is supposed to be returned from the azure notification hub when sending the message.
I am sending the message from the app backend using the SendGcmNativeNotificationAsync method.
NotificationOutcome outcome = await hub.SendGcmNativeNotificationAsync(notif, tags);
After sending the notification, the outcome.NotificationId property is empty or null. How can I get the Notification Id?
Although the outcome.Result[0].Outcome received has value
"The Notification was successfully sent to the Push Notification System"
but the notifications are not delivered to the registered device.
Also I get a tracking id in outcome.trackingid how can I use it to track the message.
I am using free version of azure portal.
Please suggest
Thanks in advance!
It took me quite some time to figure this out, because it is not clear documented, but the answer is simple: NotificationOutcome.NotificationId is always null when Azure pricing tier is not S1 (Standard).
To figure out the cause of your problem, temporary switch to the S1 pricing tier. Then you will get the NotificationId and Azure will register Per Message Telemetry.
In theory, you should be able to get the results by calling GetNotificationOutcomeDetailsAsync with the NotificationId to get more error info. It can take up to 30 minutes (!) before this call succeeds (if you call it too soon you get a MessagingEntityNotFoundException).
Unfortunately, the result State is mostly Completed, even though the message had a wrong or expired device ID.
The results in the Metrics shown in Azure for your Notification Hub are correct, but I did not find a reliable way yet to retrieve the results on a Per Message base.
Don't forget to switch back to the F1 (Free) pricing tier!
Now I'm using PushSharp library to send Apple push notifications (through APNS), but I want to migrate to Notification Hubs for robustness and scalability.
I'm planning to implement sending notification via Azure Notification Hubs using backend registration as described in this article. So:
There is a method of backend API that an iOS client calls when it has push token updated. In this method I do the registration tagging it with user id. (Previously, I stored push token to user link in DB.)
When I have some notification to send for a specific user I send it using the tag (user id). (Previously, I used APNS device token from DB.)
It seems like a working solution, but in Notification Hubs documentation it's said:
It is important to note that registrations are transient. Similar to the PNS handles that they contain, registrations expire. You can set the time to live for a registration on the Notification Hub, up to a maximum of 90 days. This limit means that they must be periodically refreshed, and also that they should not be the only store for important information. This automatic expiration also simplifies cleanup when your mobile application is uninstalled.
And that is the problem. Sometimes I need to send notification to devices that haven't updated the token for 90 days and so forth the registration. So the APNS token will still be active, but Notification Hub's registration will be invalidated. So I just lose the communication channel for the user.
How do you handle this?
Of course, I can still store tokens in DB and make a job that updates registrations periodically. But that's not what you expect from a push notification solution like Notification Hubs.
You can either refresh your registrations from the application or from your server. If you do it from your application, the app must be launched by the user in order for the registration to be refreshed.
Therefore, if you require that device registrations remain active even for apps that weren't launched for over 90 days, you have to refresh the registration via your server, and running a job in your server that would refresh the tokens seems like your only option.
I agree that Notification Hubs' decision to expire the tokens seems strange. Perhaps they had in mind the behavior of MPNS (Microsoft Push Notification Service) notification channels, which expire more often than APNS device tokens or GCM registration IDs.
Just a quick note, since the answer is 2 years old. In this blogpost Azure states:
It is important to note that registrations and installations by default no longer expire.
I assume that this makes the expire field confusing, but not a problem anymore.
UPDATE
Older notification hubs still have this issue. You need to update them to set the expiry to infinity, instructions are found in this forum post. New hubs are automatically set to infinity.
As per latest notification hub documentation, this 90 days limit has increased to lifetime, which means you don't need to re register device after 90 days.
I would like to use Azure Notification Hubs to send push notifications to users of my app running across iOS, Android and Windows Phone.
I have managed to get the basics working but I don't know how to manage the App uninstall story.
On starting, the mobile app will call my Identity Svc to get an Auth Token.
It then calls its Platform Notification service (eg Google Cloud Messaging, APNS) to get a PNS Token.
After persisting the token to local storage it will call a back-end Contact Svc to register the customer's device. This service will create a subscription to the Azure Notification hub for the device.
This is illustrated in the following diagram:
Later on a back-end publishing service will call the Contact Service requesting a push notification for a particular user id. The contact service will lookup the Id allocated to a tag on the notification hub and send a push request.
What options are available to determine when a customer uninstalls the app? Is it just a matter of trapping errors when calling "Send" on the notification hub? I guess this could work if only sending to a single user but my intention is that certain message types are to be published to multiple subscribers. On the initial registration of a device a subscription will be created for a tag of the user id but also for a more general tag such as "New Promotion". The publishing service would later want to issue a "New Promotion" notification to all devices.
Why do you need to know app uninstalls?
Notification Hubs automatically expire registrations for devices that get uninstalled.
Also, I would avoid persisting the PNSHandles in your service at all.
The current guidelines for using hubs are the following:
store the registrationIds of the registrations associated with the device in local storage. This enables you to update tags and channel information with a single update call.
Because mobile connections are not always reliable, it is best to avoid creating a new registration without being able to store the registrationId in local storage. This can result in the device registering multiple times, causing duplicate notifications. You can achieve this by using the Create Registration ID and Create or Update Registration REST APIs.
The first API returns a registrationId without actually creating a registration. When the ID has been securely stored on the device storage, the device can call the Create or Update Registration API.
So I would have your ContactSvc expose two functionalities:
a) create registration id (just call hub to get it)
b) create or update registration given (registrationId, pnsHandle, tags?)
Then your device keeps the regId in its storage, ad after getting the handle from PNS, if as regId is not there creates a new one with endpoint a), then updates the registration with pnsHandle and tags.
Note that in this way your service does not need to persist handles or UUIDs, and does not need to worry about app uninstalls.
If you are keeping track of users, one approach is to periodically (once a month?) check in your hub if its registrations are still there...
You can reach me at #eliodamaggio if this is not clear.
I am evaluating which Push Notification service to use out of Azure Mobile Services, Parse and Urban Airship.
One of the criteria is whether the service provides a way for the app to register a bespoke user Id or alias that can then easily be used when calling the service to send a push notification to an individual. This removes the need for our backend service to have a lookup table giving us the service registration ID for a given user.
Urban Airship has the alias feature: http://docs.urbanairship.com/connect/connect_audience.html#aliases
Parse has a sophisticated Installation object which behaves like a dictionary so that additional values can be added to it (like UserId). When the Parse service is called to send a Push Notification a query can be used to specify the user that will receive the message:
https://www.parse.com/docs/push_guide#sending-queries/REST
Is there an equivalent feature in Azure Mobile Services?
With Mobile Services, you would need to keep track of a user to token / channel URI / registration ID association in a table which is more work than you NEED to do. However, another feature of Windows Azure is Notification Hubs which does what you want (and much more). With Notification Hubs, from the client you say "I want to register for Notification Hubs, here are some tags you can use to push me information". Those tags can be anything you want including a User ID. Later on you can tell your Notification Hub to push to anyone registered with a certain tag. That would allow you to then push notifications out to any devices a specific user has registered.
The flow would look something like this:
Register with Push Provider (APNS, GCM, MPNS, WNS)
Send token to Notification Hubs along with tags (such as the User's ID)
Trigger a push to a specific Tag (i.e. User ID)
Notification Hubs will handle delivering a push to all devices with a Tag (again, their user ID)
Notification Hubs has client SDKs for WinPhone, WinStore, iOS, and Android so it's very easy to use from the client side. As far as triggering pushes goes, Notification Hubs exposes a REST API you can communicate with, there is a .NET SDK, a Node SDK, as well as an unofficial Java SDK. You can even use the Node SDK from Mobile Services which makes it super easy to combine authentication (i.e. getting User IDs) with data storage and push notifications. It also has lots of other features like templated push notifications so instead of specifying a different payload depending on what the device OS you're pushing to is, you can have the client application indicate how it should receive a certain type of push.