HoldList.js

import _ from 'underscore';

export default class HoldList {
  constructor() {
    this.holdList = [];
    this.runningRequestCnt = 0;
  }


  invokeAll(err, exclude) {
    if (this.holdList && this.holdList.length > 0) {
      for (const unresolvedObj of this.holdList) {
        if (unresolvedObj) {
          const {
            resolve,
            reject,
            path,
            // timestampStarted,
          } = unresolvedObj;
          if (err && reject) {
            // console.log(`request: ${path} waited for ${
            // round(now() - timestampStarted, 1)}ms and got rejected`);
            reject(err);
          } else if (err == null && resolve) {
            if (exclude && path === exclude) {
              // console.log(`request: ${path} waited for ${
              // round(now() - timestampStarted, 1)}ms and then got RESOLVED`);
              resolve(false);
            } else {
              resolve(true);
            }
          }
        }
      }
      this.holdList = [];
    }
  }

  createUnresolvedPromise(path, timestampStarted) {
    const self = this;
    return new Promise((resolve, reject) => {
      if (self.holdList == null) {
        self.holdList = [];
      }
      self.holdList.push({
        resolve,
        reject,
        path,
        timestampStarted,
      });
    });
  }


  removePromise(promise) {
    if (this.holdList && this.holdList.length > 0) {
      // remove it's reference from the Req Promise array
      this.holdList = _.reject(this.holdList,
        curPromise => curPromise === promise,
      );
    }
  }

  getWaitingRequestCnt() {
    return this.holdList && this.holdList.length;
  }

  increaseRunningRequestCnter() {
    this.runningRequestCnt += 1;
  }

  decreaseRunningRequestCnter() {
    if (this.runningRequestCnt > 0) {
      this.runningRequestCnt -= 1;
      if (this.runningRequestCnt === 0) {
        this.invokeAll();
      }
    }
  }

  getRunningRequestCnt() {
    return this.runningRequestCnt;
  }
}