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window.postMessage does not set event.origin

See original GitHub issue

Basic info:

Node.js version: 10.16.0
jsdom version: 15.2.1

When calling window.postMessage() in JSDOM, registered event listeners will receive the event, however the origin property will be set to an empty string.

post-message.js, specifically calls out event.origin (and a few others) in a TODO which I believe (not 100% sure) is why I’m having problems with this

Minimal reproduction case

const { JSDOM } = require("jsdom");
const assert = require('assert');

const dom = new JSDOM(`<!DOCTYPE html>`);

dom.window.addEventListener("message", evt => {

    // Expected: evt.origin === "https://sending-domain.com"
    //   Actual: evt.origin === ""
    assert(evt.origin === 'https://sending-domain.com')
})

dom.window.location = "https://sending-domain.com"
dom.window.postMessage('The message being posted', '*')

How does similar code behave in browsers?

In the snippet below, evt.origin inside the event listener will be equal to window.location from the frame that called window.postMessage

window.addEventListener("message", evt => { /* handle evt */ })

Issue Analytics

State:
Created 4 years ago
Reactions:15
Comments:9 (1 by maintainers)

Top GitHub Comments

8reactions

spamshakercommented, Aug 7, 2022

Did you find any alternative?

I managed to workaround it. Instead of postMessage i just dispatch a message however would be good to have it properly working

//dom.window.postMessage('TheMessage', '*');
dom.window.dispatchEvent(new MessageEvent('message', { source: window, origin: window.location.origin, data: 'TheMessage'}))

8reactions

Bloodsuckercommented, Jul 9, 2021

Apparently jsdom also doesn’t set the window event’s source property to the source’s window var. Following the OC test case to reproduce this:

const { JSDOM } = require("jsdom");
const assert = require('assert');

const dom = new JSDOM(`<!DOCTYPE html>`);

dom.window.addEventListener("message", evt => {

    // Expected: evt.origin === "https://sending-domain.com"
    //   Actual: evt.origin === ""
    assert(evt.origin === 'https://sending-domain.com')

    // It must be the dom.window, but it's null
    assert(evt.source !== null);
})

dom.window.location = "https://sending-domain.com"
dom.window.postMessage('The message being posted', '*')

Does it make sense to also create a new bug issue in here?