Web push notification is a message sent to a user through a browser from a website. They are alert-style messages delivered on the user’s desktop or mobile screen. Progressive Web Applications (PWAs) have emerged as a viable alternative to native apps because they can be downloaded, used offline, and have access to devise hardware.

In this article, I’ll teach you how to add native-like notifications to your existing web applications to make them even better. I’ll walk you through the basics of Web Push Notification and how to integrate them into your existing web apps. Finally, I’ll discuss current requirements and browser support.

Web Push Notification Protocol

Web Push Notification is a new protocol. It allows web applications to behave like native programs and receive messages from a server at any time, even if the web app is not active or loaded in the browser. When users aren’t using your app, you can send them urgent and relevant notifications to entice them back. Best web development companies in Chennai like Havro are providing services implementing web push notifications protocol.

Web Sockets vs. Web Push

I’d like to discuss the distinctions between Web Push and Web Sockets before getting into the specifics of the technology. To begin, let’s look at what they have in common. Web Push and Web Sockets are meant to enable real-time communication between the web application and the application server, as well as to transfer real-time data and updates from the application server to the web application.

The following are the distinctions:

  • Only when a web page is loaded and active can Web Sockets be used. Web Push Notification, on the other hand, can be used at any time, including when the application is active, inactive, or not loaded, and even when the browser is not open or closed.
  • Web Push data must be encrypted, and each communication must be within a certain size limit (it must not be larger than 4Kb). There’s also a count limit on the number of messages you can send (the exact limit value depends on the browser). Some browsers (such as Chrome) may also require the user to see a notification every time a message is received. When you utilize Web Sockets, you don’t have any of these restrictions: you may send an unlimited amount of unencrypted messages of any size and treat them any way you want; you can display a notification, silently update the data in your application, or do nothing at all.
  • When a user interacts with your online app, the basic guideline is to use Web Sockets to provide regular data updates to the app. Use Web Push Notifications to send urgent and vital notifications to a user that must be received right away, regardless of whether or not the user is currently using your application.

Concepts of Technology

Let’s get into the technology’s technical aspects. I’d like to demonstrate the points using a game with unique rules, players, and rounds. I’ll begin by describing the game’s players. In this game named Web Push Notifications, there are five players.

  • Web Application
  • Service Worker
  • Browser
  • Application Server
  • Push Server

The browser vendor implements the Push Server service, which acts as a communication bridge between your application server and a browser. It’s in charge of sending messages from your application server to your browser.

Demonstrating Web Push Notifications with a Game

I’ll show you how to integrate a web push notification into your apps using a game. The World Wide Web Consortium and the Internet Engineering Task Force have released various specifications that outline the game’s rules:

The Push API (Application Programming Interface) specification describes the communication between the browser and the web application or service worker connected with this application.

The Notifications API specification describes how to display various sorts of notifications as well as how to handle notifications. The Web Push Protocol specifies the communication between the Application Server and the Push Server.

There are also specifications for push message encryption and application server identification, which allow your application server to confirm that it is authorized to transmit messages to your user.

Permission request

If your web app doesn’t have notification permissions when you run subscribe(), the browser will request them on your behalf. However, you have another option: you can explicitly seek permissions by contacting Notification directly using the request permission function. This method will deliver a promise that resolves to the user’s chosen permission. This can take the form of granted, denied, or default.

Messages Encryption 

A Push message may or may not contain any data. The POST request will have an empty body in this situation, and the service worker may need to gather some data before sending the user a notification. Alternatively, the application server can provide a payload along with the push message to save the service worker from having to make an extra request. All payload data, however, must be encrypted. This is a crucial point. Because you trust your application server, HTTPS allows secure communication between the browser and the application server.

Handling the Push Message

The browser, on the other hand, picks which push server to utilize to provide the data, thus you, as the application developer, have no say. Only HTTPS ensures that no one may access or modify the message while it is being sent to the push server. However, once the data has been received by the push server, it can be re-transmitted or modified. To avoid this issue, encrypt the data such that the payload data cannot be read or modified by a push server.

The Application Server gave the user a push message, which was validated by the Push Server and forwarded to the browser. The Service Worker was woken up by the Browser, which issued a push event to it. This was handled by the Service Worker, who processed the push message.

I’d want to touch on two crucial points:

  • Firefox permits a set quantity (quota) of push messages to be sent to an application without displaying a Notification, which is refreshed each time the site is visited. Chrome, on the other hand, demands that every push message include a notice, and if you don’t include one, Chrome will display a default notification.
  • The wait until method instructs the browser to keep the Service Worker active until the promise supplied to it is resolved. If you don’t include this method, the Browser will instantly shut down the Service Worker, and the Notification will be hidden.