Using public channels with Nodejs

Using public channels with Nodejs

Public channels do not require authentication. Public channels can be used for features without sensitive information, such as these use cases:

• Notify all users with the e-commerce page loaded when a new product goes on sale.
• Live chat similar to YouTube chat.
• Trigger updates for all clients currently viewing a page when it changes.

Frontend

<html>
    <body>
       <h1>Pusher test</h1> 
      <script>
        document.addEventListener('DOMContentLoaded', function() {
            var pusher = new Pusher("RESSONANCE_APP_ID", {
                cluster: "default",
                wsHost: "websocket.ressonance.com",
                wsPort: 443,                  
                wssPort: 443,                 
                forceTLS: true,               
                disableStats: true,            
                enabledTransports: ["ws", "wss"]
            });

            var channel = pusher.subscribe("public-channel");

            channel.bind("new-release", (data) => {
                alert("New release", data.release);
            });
        });
      </script>
      <script src="https://js.pusher.com/8.3.0/pusher.min.js"></script>  
    </body>
</html>

Backend

npm install --save pusher

This is a small Nodejs example application.

const http = require("http");
const Pusher = require("pusher");

var pusher = new Pusher({
  appId: "RESSONANCE_APP_ID",
  key: "RESSONANCE_APP_KEY",
  secret: "RESSONANCE_APP_SECRET",
  host: "websocket.ressonance.com",
  port: 443,
  useTLS: true
});

const sendJson = (res, statusCode, payload) => {
  res.writeHead(statusCode, { "Content-Type": "application/json" });
  res.end(JSON.stringify(payload));
};

const server = http.createServer((req, res) => {
  res.setHeader("Access-Control-Allow-Origin", "*");
  res.setHeader("Access-Control-Allow-Methods", "GET,POST,OPTIONS");
  res.setHeader("Access-Control-Allow-Headers", "Content-Type");

  if (req.method === "OPTIONS") {
    res.writeHead(204);
    res.end();
    return;
  }

  if (req.method === "GET" && req.url === "/send-public-event") {
    pusher
      .trigger("public-channel", "new-release", { release: "hello world" })
      .then(() => sendJson(res, 200, { message: "Event sent!" }))
      .catch(() => sendJson(res, 500, { message: "Failed to send event." }));
    return;
  }

  sendJson(res, 404, { message: "Not found." });
});

const port = process.env.PORT || 5000;
server.listen(port);