wg-little-tools/superTask/superTask.mjs

常用工具类

/**
 * @description 并发任务
 */

export class SuperTask {
  constructor(parallelCount = 2) {
      this.parallelCount = parallelCount; // 最大并发数
      this.runningCount = 0; // 正在运行的任务数
      this.taskList = []; // 任务集合
  }

  add(task) {
      return new Promise((resolve, reject) => {
          this.taskList.push({
              task,
              resolve,
              reject
          });
          this.run();
      })
  }

  run() {
      if (this.taskList.length && this.runningCount < this.parallelCount) {
         const { task, resolve, reject } = this.taskList.shift(); // 先进先出
          this.runningCount++;
         task().then(resolve, reject).finally(() => {
             this.runningCount--;
             this.run();
         })
      }
  }
}