Web push notifications - push-notification

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.

Related

React native app sending push notification while device is offline

I'm about to develop an app similar to a birthday reminder and I plan to use firebase for push notifications but what makes me second question my choice is whether users will be able to receive a birthday notification if they are offline(not connected to internet for the whole birthday day). I know firebase has some offline persistence support but I'm not sure if this includes push notifications support. Are there any options to achieve that with firebase or with any other tool compatible with react native?
If the device is not connected to the internet, it is going to be impossible to deliver messages to it through Firebase Cloud Messaging or other internet protocols.
The common way to deal with such a scenario is to deliver the message to the device when the user does have an internet connection, and then only display it once it's the right time. By sending a data-only message through FCM, your application code controls exactly what happens with the message data.
There are essentially two types of notifications: in app messaging and cloud messaging. Both are offered by Firebase: In App Messaging and FCM (Firebase Cloud Messaging).
The details you've given about your app is a little bit vague but if you're asking for push notifications, then FCM does the job. FCM will send notification when the app is on background or killed (exited out). When you say device is offline I'm assuming you mean when the user isn't using the phone. Yes, the notification will still come.
https://firebase.google.com/docs/cloud-messaging

Firebase: How to send push notifications in batches to avoid problem with backend overload?

We have an app (iOS, Android) where we send push notifications to from the Firebase web interface to all the registered users.
The backend system cannot handle the peak load that occurs when all the users are pulled into the app calling the REST API from the push notifications.
Is there a way to split the registered users to send the push notifications little by little at an appropriate rate?
I suspect that this has to be done programmatically. C#?
Question with workarounds handling peak times when sending push notifications
The web console for sending notifications with Firebase Cloud Messaging does not have a way to throttle message delivery. It's an interesting concern though, so I'd recommend filing a feature request.
For the moment though, I can think of two options:
Create multiple audiences that cover your entire user base, and then send to each audience at a different time.
Use the FCM API to send out the messages to your users in batches.

How to create a "real" iOS push notification from Firebase topic messages if the app is not running?

As far as I understand messages on subscribed topics are received through the socket connection.
So while the app is running in the background I could create local notifications and "fake" notification that pop up on the home screen and are visible in the notification center.
But is there a way to receive topic pushes if the app is closed/not running in the background?
I'm grateful for any kind of feedback as I couldn't find any documentation regarding that specific use case.
Just to clarify: I am talking about (subscribed) topic messages in firebase NOT the firebase messages. I am used to the generic iOS push notifications handling and the involved lifecycle methods. All I need to know is how firebase topic messages can be sent via apns notifications.
With Firebase Messaging you can send notifications so the app is closed (it must be installed), basically it is configured in the AppDelegate the methods and configuration according to your need, you can see more information here Firebase Messaging
No you can’t, setup your configration in apo delegate and firebase settings, when the app is offline firebase talked directly to the APN which called the nitification center in your iphone but you don’t have access on it during the application is closed.

Web Push. fetching web pushes sent while offline?

I am coding a vue.js app using web pushes with Firebase Cloud Messaging and I wondered if it was possible to send a web push to a user and in case the user was offline, to somehow store it for later display when the user opens the app again. Is there a principled approach to this problem, i.e. managing web pushes when the end user is offline?
The reason I am asking this is that, so far, all the web push notifications I've committed to FCM server with tokens of offline clients (i.e. desktop browsers) went into oblivion. To be sure, FCM didn't try pushing the notification again when the clients went back online.
For this reason I am considering coding a self-made dispatcher to manage web push for offline clients, but I need to make sure my efforts are worth it.
updated: I am now able to display notifications sent to an offline client after coming back online using appropriate time_to_live values. However, only the latest notification is displayed. How is there any specific reason why?
FCM's default behavior is exactly like that. From the docs:
If the device is not connected to FCM, the message is stored until a connection is established (again respecting the collapse key rules). When a connection is established, FCM delivers all pending messages to the device.

Is it a good idea to use push notifications for mobile chat applications? (Android, iOS)

The idea of using the push notifications is only to have a notification mechanism that will send a notification when there is a new message waiting to download from the backend service: all the notifications are of the same type e.g. "refresh messages from the server" (the same for Android and iOS).
Are there any limits for the Apple/Google push notifications services?
Assuming that my application will handle more that 100k active users (or even 1M or more users) - would there be any problem with the Apple Push Notifications or GCM services?
If using the push notifications for such a service is not a good idea then what is other solution that could be used for mobile chat applications?
Don't forget that on iOS user may forbid sending notifications, so your app won't receive any even in foreground. Thus, you need to implement your own push mechanism.
Need for push notifications
Especially on iOS you don't have a choice but to use their push notifications service APNS. There is no other way to receive notifications immediately because iOS may kill or neglect the TCP connections of your background app.
On Android it seems possible to use your own background TCP connection to avoid having to use push notifications. But you may still consider the use of the push notifications through GCM for the sake of improved battery usage.
Pricing
Neither APNS (iOS) nor GCM (Android) charge you for the service and you are allowed to send an unlimited number of messages.
Limitations and Requirements
Both services will delete message, when there are too many messages accumulated in the queue for an offline device - which makes sense because there is no point in delivering those messages hours later. You have to take that in to account, when writing your app (just do a poll when going back online).
Depending on the app you are writing, there may also be privacy concerns. Even if you encrypt the message itself, at least Apple/Google know when a notification is sent to a certain device, which may be a deal-breaker for certain high-security applications.
You will also need a server that is able to communicate to both APNS and GCM. There are open source solutions for that (e.g. easyApns for iOS and python-gcm for Android), but how easy their integration is depends on your server and the language it is written in.

Resources