maxun-core
Version:
Core package for Maxun, responsible for data extraction
46 lines (45 loc) • 1.62 kB
TypeScript
/**
* Concurrency class for running concurrent tasks while managing a limited amount of resources.
*/
export default class Concurrency {
/**
* Maximum number of workers running in parallel. If set to `null`, there is no limit.
*/
maxConcurrency: number;
/**
* Number of currently active workers.
*/
activeWorkers: number;
/**
* Queue of jobs waiting to be completed.
*/
private jobQueue;
/**
* "Resolve" callbacks of the waitForCompletion() promises.
*/
private waiting;
/**
* Constructs a new instance of concurrency manager.
* @param {number} maxConcurrency Maximum number of workers running in parallel.
*/
constructor(maxConcurrency: number);
/**
* Takes a waiting job out of the queue and runs it.
*/
private runNextJob;
/**
* Pass a job (a time-demanding async function) to the concurrency manager. \
* The time of the job's execution depends on the concurrency manager itself
* (given a generous enough `maxConcurrency` value, it might be immediate,
* but this is not guaranteed).
* @param worker Async function to be executed (job to be processed).
*/
addJob(job: () => Promise<any>): void;
/**
* Waits until there is no running nor waiting job. \
* If the concurrency manager is idle at the time of calling this function,
* it waits until at least one job is completed (can be "presubscribed").
* @returns Promise, resolved after there is no running/waiting worker.
*/
waitForCompletion(): Promise<void>;
}