Building Applications with Spring 5 and Vue.js 2

Introduction to SockJS

Under the hood, the SockJS client will try to use the native WebSocket that the browser provides. If it is not available, it will fall back to other transport protocols, such as XHR-Streaming and  XHR-Polling. Its API is very simple to use. The following is an example of establishing a WebSocket connection with a local server at the /rt path:

let socket = new SockJS('http://localhost:8080/rt')socket.onopen = function (event) {  // Connection established  console.log(socket.readyState)}socket.onmessage = function (message) {  // Message received via WebSocket}socket.onclose = function (event) {  // Connection closed}socket.onerror = function (error) {  // An error occurred}

As you can see, it has four event handlers:

• The ...