ServiceWorkerMessageEvent.ports

The ports read-only property of the ServiceWorkerMessageEvent interface returns an array of MessagePort objects connected with the message channel the message is being sent through.

Syntax

var myPorts = ServiceWorkerMessageEventInstance.ports;

Value

An array of MessagePort objects.

Examples

When the following code is used inside the main thread to set up a message channel between it and a service worker for sending messages between the two, the event object of onmessage will be a ServiceWorkerMessageEvent.

navigator.serviceWorker.ready.then(function(reg) {  

  ...

      // set up a message channel to communicate with the SW
      var channel = new MessageChannel();
      channel.port1.onmessage = function(e) {
        console.log(e.ports);
        handleChannelMessage(e.data);
      }
      
      mySW = reg.active;
      mySW.postMessage('hello', [channel.port2]);
  });

Specifications

Browser compatibility

See also

• Using Service Workers
• Service workers basic code example
• Is ServiceWorker ready?
• Channel Messaging