Using public channels with Java

Using public channels with Java

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

mvn dependency:get -Dartifact=com.pusher:pusher-http-java:1.4.0

This is a small Java example application.

import com.pusher.rest.Pusher;
import com.pusher.rest.PusherOptions;
import java.util.Map;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.web.bind.annotation.CrossOrigin;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

@SpringBootApplication
@RestController
@CrossOrigin(origins = "*")
public class Application {

  private final Pusher pusher;

  public Application() {
    PusherOptions options = new PusherOptions()
      .setHost("websocket.ressonance.com")
      .setUseTLS(true);

    this.pusher = new Pusher("RESSONANCE_APP_ID", "RESSONANCE_APP_KEY", "RESSONANCE_APP_SECRET", options);
  }

  @GetMapping("/send-public-event")
  public String sendPublicEvent() {
    pusher.trigger("public-channel", "new-release", Map.of("release", "hello world"));
    return "Event sent!";
  }

  public static void main(String[] args) {
    SpringApplication.run(Application.class, args);
  }
}