AbortController
The AbortController
interface represents a controller object that allows you to abort one or more Web requests as and when desired.
You can create a new AbortController
object using the AbortController()
constructor. Communicating with a DOM request is done using an AbortSignal
object.
Constructor
AbortController()
-
Creates a new
AbortController
object instance.
Properties
AbortController.signal
Read only-
Returns an
AbortSignal
object instance, which can be used to communicate with, or to abort, a DOM request.
Methods
AbortController.abort()
-
Aborts a DOM request before it has completed. This is able to abort fetch requests, consumption of any response bodies, and streams.
Examples
In the following snippet, we aim to download a video using the Fetch API.
We first create a controller using the AbortController()
constructor, then grab a reference to its associated AbortSignal
object using the AbortController.signal
property.
When the fetch request is initiated, we pass in the AbortSignal
as an option inside the request's options object (the {signal}
below). This associates the signal and controller with the fetch request and allows us to abort it by calling AbortController.abort()
, as seen below in the second event listener.
let controller;
const url = "video.mp4";
const downloadBtn = document.querySelector('.download');
const abortBtn = document.querySelector('.abort');
downloadBtn.addEventListener('click', fetchVideo);
abortBtn.addEventListener('click', function() {
if (controller) controller.abort();
console.log('Download aborted');
});
function fetchVideo() {
controller = new AbortController();
const signal = controller.signal;
fetch(url, { signal })
.then(function(response) {
console.log('Download complete', response);
})
.catch(function(e) {
console.log('Download error: ' + e.message);
});
}
Note: When abort()
is called, the fetch()
promise rejects with a DOMException
named AbortError
.
You can find a full working example on GitHub; you can also see it running live.
Specifications
Specification |
---|
DOM Standard # interface-abortcontroller |
Browser compatibility
BCD tables only load in the browser
See also
- Fetch API
- Abortable Fetch by Jake Archibald