postmessage-promise

 

Simple promise based post message / listener.

Uses MessageChannels under the hood.

Usage

``js
import { onMessage, sendMessage } from 'promise-postmessage';

onMessage(
async (event) => {
// some async operation
const resp = await foo(event.data);
return resp;
},

// source frame
window.parent
);

const resp = await sendMessage(
// target frame window.
document.getElementById('iframe')
.contentWindow

// Message payload
{ foo: 'bar' },
);
`

$3


`js
import { onMessage, sendMessage } from 'promise-postmessage';

const frame1 = document.getElementById("frame1").contentWindow;
const frame2 = window.parent; // Or could be another child iframe.

onMessage((event) => {
return sendMessage(frame2, event.data);
}, frame1);

onMessage((event) => {
return sendMessage(frame1, event.data);
}, frame2);
``