2022-07-12 09:00:22 +02:00

115 lines
3.5 KiB
JavaScript

// Copyright (c) Microsoft Corporation.
// Licensed under the MIT license.
/// <reference path="../shims-public.d.ts" />
const listenersMap = new WeakMap();
const abortedMap = new WeakMap();
/**
* An aborter instance implements AbortSignal interface, can abort HTTP requests.
*
* - Call AbortSignal.none to create a new AbortSignal instance that cannot be cancelled.
* Use `AbortSignal.none` when you are required to pass a cancellation token but the operation
* cannot or will not ever be cancelled.
*
* @example
* Abort without timeout
* ```ts
* await doAsyncWork(AbortSignal.none);
* ```
*/
export class AbortSignal {
constructor() {
/**
* onabort event listener.
*/
this.onabort = null;
listenersMap.set(this, []);
abortedMap.set(this, false);
}
/**
* Status of whether aborted or not.
*
* @readonly
*/
get aborted() {
if (!abortedMap.has(this)) {
throw new TypeError("Expected `this` to be an instance of AbortSignal.");
}
return abortedMap.get(this);
}
/**
* Creates a new AbortSignal instance that will never be aborted.
*
* @readonly
*/
static get none() {
return new AbortSignal();
}
/**
* Added new "abort" event listener, only support "abort" event.
*
* @param _type - Only support "abort" event
* @param listener - The listener to be added
*/
addEventListener(
// tslint:disable-next-line:variable-name
_type, listener) {
if (!listenersMap.has(this)) {
throw new TypeError("Expected `this` to be an instance of AbortSignal.");
}
const listeners = listenersMap.get(this);
listeners.push(listener);
}
/**
* Remove "abort" event listener, only support "abort" event.
*
* @param _type - Only support "abort" event
* @param listener - The listener to be removed
*/
removeEventListener(
// tslint:disable-next-line:variable-name
_type, listener) {
if (!listenersMap.has(this)) {
throw new TypeError("Expected `this` to be an instance of AbortSignal.");
}
const listeners = listenersMap.get(this);
const index = listeners.indexOf(listener);
if (index > -1) {
listeners.splice(index, 1);
}
}
/**
* Dispatches a synthetic event to the AbortSignal.
*/
dispatchEvent(_event) {
throw new Error("This is a stub dispatchEvent implementation that should not be used. It only exists for type-checking purposes.");
}
}
/**
* Helper to trigger an abort event immediately, the onabort and all abort event listeners will be triggered.
* Will try to trigger abort event for all linked AbortSignal nodes.
*
* - If there is a timeout, the timer will be cancelled.
* - If aborted is true, nothing will happen.
*
* @internal
*/
// eslint-disable-next-line @azure/azure-sdk/ts-use-interface-parameters
export function abortSignal(signal) {
if (signal.aborted) {
return;
}
if (signal.onabort) {
signal.onabort.call(signal);
}
const listeners = listenersMap.get(signal);
if (listeners) {
// Create a copy of listeners so mutations to the array
// (e.g. via removeListener calls) don't affect the listeners
// we invoke.
listeners.slice().forEach((listener) => {
listener.call(signal, { type: "abort" });
});
}
abortedMap.set(signal, true);
}
//# sourceMappingURL=AbortSignal.js.map