Intercept XMLHttpRequest and send a Promise

问题

I am building a proxy for a video player which can intercept the http requests and send back the response using a Promise which can be resolved asynchronously

I have found this way of intercepting a http request

// save original `send` method
const origSend = XMLHttpRequest.prototype.send;

// redefine `send` method
// you could also pass extra parameters if needed
XMLHttpRequest.prototype.send = (...origParams) => {
  console.log('send called');
  origSend(...origParams);
}

Now I don't want to return the response using origSend like in the above way. What I need is to send the url to my backend engine which will download the content and send me the bytearray which I need to send back to the video player. To achieve this I was thinking of using a Promise which will be resolved by my backend engine when it is able to complete the request

Now what I am unsure is how to return the bytearray fetched by my engine back to the video player from the intercepted code. Would be great to find some relevant code snippets.

来源：https://stackoverflow.com/questions/63864504/intercept-xmlhttprequest-and-send-a-promise