egirlskey/packages/frontend/src/scripts/worker-multi-dispatch.ts
2023-10-30 19:38:27 +09:00

82 lines
2.7 KiB
TypeScript

/*
* SPDX-FileCopyrightText: syuilo and other misskey contributors
* SPDX-License-Identifier: AGPL-3.0-only
*/
function defaultUseWorkerNumber(prev: number, totalWorkers: number) {
return prev + 1;
}
export class WorkerMultiDispatch<POST = any, RETURN = any> {
private symbol = Symbol('WorkerMultiDispatch');
private workers: Worker[] = [];
private terminated = false;
private prevWorkerNumber = 0;
private getUseWorkerNumber = defaultUseWorkerNumber;
private finalizationRegistry: FinalizationRegistry<symbol>;
constructor(workerConstructor: () => Worker, concurrency: number, getUseWorkerNumber = defaultUseWorkerNumber) {
this.getUseWorkerNumber = getUseWorkerNumber;
for (let i = 0; i < concurrency; i++) {
this.workers.push(workerConstructor());
}
this.finalizationRegistry = new FinalizationRegistry(() => {
this.terminate();
});
this.finalizationRegistry.register(this, this.symbol);
if (_DEV_) console.log('WorkerMultiDispatch: Created', this);
}
public postMessage(message: POST, options?: Transferable[] | StructuredSerializeOptions, useWorkerNumber: typeof defaultUseWorkerNumber = this.getUseWorkerNumber) {
let workerNumber = useWorkerNumber(this.prevWorkerNumber, this.workers.length);
workerNumber = Math.abs(Math.round(workerNumber)) % this.workers.length;
if (_DEV_) console.log('WorkerMultiDispatch: Posting message to worker', workerNumber, useWorkerNumber);
this.prevWorkerNumber = workerNumber;
// 不毛だがunionをoverloadに突っ込めない
// https://stackoverflow.com/questions/66507585/overload-signatures-union-types-and-no-overload-matches-this-call-error
// https://github.com/microsoft/TypeScript/issues/14107
if (Array.isArray(options)) {
this.workers[workerNumber].postMessage(message, options);
} else {
this.workers[workerNumber].postMessage(message, options);
}
return workerNumber;
}
public addListener(callback: (this: Worker, ev: MessageEvent<RETURN>) => any, options?: boolean | AddEventListenerOptions) {
this.workers.forEach(worker => {
worker.addEventListener('message', callback, options);
});
}
public removeListener(callback: (this: Worker, ev: MessageEvent<RETURN>) => any, options?: boolean | AddEventListenerOptions) {
this.workers.forEach(worker => {
worker.removeEventListener('message', callback, options);
});
}
public terminate() {
this.terminated = true;
if (_DEV_) console.log('WorkerMultiDispatch: Terminating', this);
this.workers.forEach(worker => {
worker.terminate();
});
this.workers = [];
this.finalizationRegistry.unregister(this);
}
public isTerminated() {
return this.terminated;
}
public getWorkers() {
return this.workers;
}
public getSymbol() {
return this.symbol;
}
}