I have a xamarin forms project that uses an azure mobile service with offline sync. The iOS client is working perfectly in that it can save things locally and sync in the background. The context of my app is a game scorekeeper. So, there are two players involved both scoring on the single device.
What I would like to happen is for the "visiting" player or the player who doesn't own the device in use (ie not the primary user) to have their device sync when new data is pushed from the device in use.
Device A pushes new content, Device B somehow knows to pull new content.
This could open the door for each player to score on their own devices in a future version.
Anyway, the question is how do I tell device B to pull? Do I use APN type notification and that triggers a sync, or SignalR to tell it to sync?
The best approach on sync scenarios like this is to have your background sync process going at set intervals but then also trigger your sync process from a specific Push Notification.
If you send a Push Notification with a "special" payload (i.e. meaning something that just means to sync to your code). Then start the sync once the device receives that.
This article might help with Azure Push Notifications with Xamarin Forms: http://www.xamarinhelp.com/push-notifications/
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I am making a website and one of the features is that whenever a contract is nearing its end, the user should be notified about it. So I was looking for a way to notify users and I found out about push notifications.
Now, there are lots of things written about it. I heard a lot about Google Cloud Messaging, Firebase Cloud Messaging and Service Workers.
Now the thing is that my website will probably be on an Intranet. So maybe I won't be able to use GCM/FCM.
But I have a few questions regarding GCM, FCM and Service-Workers:
Why do I need FCM/GCM?
What is the difference between FCM and Service Workers?
Is there a way to push notifications even if the browser is closed?
Because my website is on an Intranet, is there another way to push notifications to the users?
1. Why do I need FCM/GCM?
You may check here the features of FCM.
Notification payload: 4KB, Message payload: 2KB. Note that the notification includes device and app information too.
Stores 100 notification/messages per device if the device is offline.
Stores notification/messages for 30 days if the device is offline, and deleted them all one this period is over and the device is still offline.
FCM supports Android and iOS devices, and even chrome web apps. The notifications are sent to iOS devices in this way: App Server -> FCM -> Apple Push Notification Server (APNs) -> iOS device -> App.
GCM supports 1 million subscribers while FCM do not have this limitation.
Supports programming in C++.
Less requirements for coding.
2. What is the difference between FCM and Service Workers?
Service Worker is a background service that handles network requests. Ideal for dealing with offline situations and background syncs or push notifications. Cannot directly interact with the DOM. Communication must go through the Service Worker’s postMessage method. Service Workers are pretty perfect for creating offline-first web apps. They let you interact with the server when you can (to fetch new data from the server, or push updated info back to the server), so your app can work regardless of your user’s connectivity.
While using FCM, you can notify a client app that new email or other data is available to sync. You can send notification messages to drive user reengagement and retention. For use cases such as instant messaging, a message can transfer a payload of up to 4KB to a client app.
3. Is there a way to push notifications even if the browser is closed?
Check this thread: Notifications while browser is closed
4. Because my website is on an Intranet, is there another way to push notifications to the users?
Unfortunately, I don't see any documentation regarding this.
Hope my answers help you.
I am writing a connected home device (alarm system) which can receive events/messages from a mobile device (e.g. a message to dismiss an alarm).
Example of a scenario (mobile device is an iphone for the sake of the example):
Connected device at home sounds alarm and notifies the iphone (using iOS push notifications, not firebase)
iphone user brings up the app, and clicks "dismiss"
connected device gets "dismiss" message and stops the alarm
I was thinking about using firebase's live database for this interaction, so the iphone app would set a db field, and the home device (which runs python) would subscribe to this field and see that it has been set.
The problem is that this is not a very clean implementation, as I would need the home device to turn off the dismiss field after it has received it, so that subsequent dismiss event can be recognized.
Essentially I am implementing messaging on top of a live database.
Is there a cleaner way to do this in firebase?
If not, is this a reasonable implementation?
Are there alternatives to firebase that take care of such a scenario?
What I really need is a web-based event-broker as-a-service...
I would suggest looking at https://github.com/firebase/firebase-queue
There are a few examples of usage on SO such as My Firebase Queue doesn't do anything after I changed to Firebase 3
Many of our developers are using Firebase with a server to perform tasks like background processing, integrating with third party APIs, or handling advanced authentication requirements. Today, we're introducing Firebase Queue, a fault-tolerant multi-worker job pipeline built on Firebase.
If you're writing your server code in Node, Firebase Queue makes it easy to handle background jobs with a worker queue. We're already using it in our private backups feature, where we reliably handle hundreds of jobs per day across multiple machines. ( https://firebase.googleblog.com/2015/05/introducing-firebase-queue_97.html )
I am in the beginning stages of developing a react native mobile application. I wanted to get insights on the following on a conceptual level relating to the below.
Say the application goes into the suspended state (as mentioned here) at which point there is no application code being executed. Subsequently, the server sends a push notification based on some changes to the data. It seems that (at least on IOS) there is a way to use push notifications to initiate a download in the background. My questions are:
Is there a way to initiate this download in react native post a push notification when application is suspended?
Is there a way to synchronize the Firebase data with the application post such a push notification while the application is running in background if (1) above is possible?
Any hints on these will be of great help. Thank you.
I want to create a chat application for ios, android and windows phones as well as it should work with browsers in the future. My search led me to using Signal R with Azure Mobile Services(AMS).
My questions:
1) SignalR uses Websockets under the hood. Is websocket supported in Android, IOS, windows phones and all mobile/desktop browsers??
2) If not, how will it effect using SignalR with AMS?
3) Or should I just use Push notifications supported in AMS?
4) Any sample app/code snippet you can share. Note that I will be using Xamarin for my app development.
5) Any advice you can give for same.
Azure Mobile Services has SignalR integrated, and Azure Mobile Services provide a SDK for client apps, I suppose it is provide out-of-the box
See
Real-time with ASP.NET SignalR and Azure Mobile .NET Backend
Master the Managed Azure Mobile Services Backend–Part Four
High value mobile backend capabilities included
You will find many capabilities included in Mobile Services and readily available for your Web API. Mobile push notifications, real-time notifications with SignalR (auto-scaled out), social auth for your consumer apps, offline data sync for occasionally connected scenarios, to name a few.
Samples:
https://github.com/gshackles/RealTimeGallery
Sample to help developers to implement Push Notification, through Azure Notification Hubs, in mobile applications.
Note:
Azure Mobile Service is based in WebAPI!
For that you want, you should not use only Push Notification because Push Notification in iOS could not be read by the application if the user ignore it, only in android or windows you can get and save it. Another thing that can be a problem is the fact if the app is running you should not show the push notification and you should show a pop up with the notification... and the push notification can have a delay from the Push Notification Service (Apple, GCM, WNS...). Push notification are a notification that something happened in the app when the user is not using it.
In my opinion you should use AMS+SignalR for realtime communication and then Push Notification for update the user then he not using the app.
Using SignalR is efficient to save yourself from hitting any push notification cap if you ant to limit your costs. But you'll need to either turn notifications on/off at the right time when the app becomes active or inactive, otherwise the app may go in the background and push notifications won't be sent.
You can use a pure push approach where notifications are shown when the app is inactive/in the background, and whenthe app is active, you simply intercept the notification in the app, consume it and cancel it so it doesn't get shown. I have written a blog post on this approach along with 3 samples in Github for iOS, Android and Windows Universal at http://www.ageofmobility.com/2014/10/06/azurechatr-building-a-cross-platform-chat-app-for-windows-ios-android/.
I want to collect device attributes and send them to the mdm server using push notification.
Steps involved are:
create a configuration profile with mdm payload
get device token
use apple push notification service to send a notification to the device.
get back device attributes
do same with multiple devices which the company manages
Questions:
Will the user always need to act on a message or I can send a message onto the device without user action and get the work done?
Do I need an app on the device to send back the token?
It sounds like you're trying to use push notifications to poll iOS devices and return information.
Push notifications do not provide a mechanism to execute code on a device without user interaction. You would have to have an application loaded on the device, and the user would have to click through from the notification to your app.
In iOS, applications generally don't run unless the user is actively interacting with them. There are a few exceptions (e.g. background audio.)
You do need to have an app running to get the device token. You call registerForRemoteNotificationTypes. See APNs docs for more information.
Edited to add more information:
Looks like the MDM protocol uses push notifications to do just what you describe. However, there's nothing about it in Apple's "Local and Push Notification Programming Guide" (linked above).
Apparently Apple keeps tight control over the MDM documentation (see here and here).
However, I did find this paper from blackhat describing how the system works.
My earlier point about not executing arbitrary code on a device without user interaction still applies. There's a finite set of commands that can be executed (see Appendix A).
I came across this question when searching for iOS push notification access payload without user interaction - Just want to add that, in iOS 7 and above, it is possible to send silent push notifications to app, and app can process them without user interaction.
However, I've also found some discussions saying that the silent push notifications are not delivered reliably, in this SO post. That's why I'm still looking for alternate ways to retrieve payloads of the normal remote push notifications. Doesn't look like there's a way.