communication between Cypress and Vue app

communication.js

// ======CYPRESS_SIDE========
//$window is available with cy.window() or in Cypress.Command

 // $window = window's object | postMessage(options) 
 // postMessage allows cross-origin communication between Window objects
 // Direction: CYPRESS => APP

 $window.postMessage(OBJECT);

// On app side, don't forget to add a check about the origin 
// inject variable and listener for dev/test env

 // get the data in window's variable
 $window['debug_controls']

// ======APP_SIDE========

// check environment, I don't want to share it in production
 if (process.env.NODE_ENV == 'development') {
    
    // set data in window's object. (allow to be share with test,   
    // Direction: app => test
    window['debug_controls'] = JSON.stringify([DATA]);
    
    // listen message from postMessage (from your test and other emitters)
    window.addEventListener("message", (m) => {
        // your business, feel free to check origin of the message, 
        // in my case Webpack posted messages too.
    });
}