@barchart/common-js/dist/cjs/timing/RateLimiter.js

Library of common JavaScript utilities

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var __defProp = Object.defineProperty;
var __getOwnPropDesc = Object.getOwnPropertyDescriptor;
var __getOwnPropNames = Object.getOwnPropertyNames;
var __getProtoOf = Object.getPrototypeOf;
var __hasOwnProp = Object.prototype.hasOwnProperty;
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  for (var name in all)
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  return to;
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var __toESM = (mod, isNodeMode, target) => (target = mod != null ? __create(__getProtoOf(mod)) : {}, __copyProps(
  // If the importer is in node compatibility mode or this is not an ESM
  // file that has been converted to a CommonJS file using a Babel-
  // compatible transform (i.e. "__esModule" has not been set), then set
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  isNodeMode || !mod || !mod.__esModule ? __defProp(target, "default", { value: mod, enumerable: true }) : target,
  mod
));
var __toCommonJS = (mod) => __copyProps(__defProp({}, "__esModule", { value: true }), mod);
var RateLimiter_exports = {};
__export(RateLimiter_exports, {
  default: () => RateLimiter
});
module.exports = __toCommonJS(RateLimiter_exports);
var assert = __toESM(require("./../lang/assert.js"));
var is = __toESM(require("./../lang/is.js"));
var promise = __toESM(require("./../lang/promise.js"));
var import_Disposable = __toESM(require("./../lang/Disposable.js"));
var import_Queue = __toESM(require("./../collections/Queue.js"));
var import_Scheduler = __toESM(require("./Scheduler.js"));
class RateLimiter extends import_Disposable.default {
  #windowMaximumCount;
  #windowDurationMilliseconds;
  #scheduler;
  #workQueue;
  #windowStart;
  #windowCounter;
  /**
   * @param {number} windowMaximumCount - The maximum number of items which can be processed during a timeframe (positive integer).
   * @param {number} windowDurationMilliseconds - The number of milliseconds in the timeframe (positive integer).
   */
  constructor(windowMaximumCount, windowDurationMilliseconds) {
    super();
    assert.argumentIsValid(windowMaximumCount, "windowMaximumCount", (x) => is.integer(x) && is.positive(x));
    assert.argumentIsValid(windowDurationMilliseconds, "windowDurationMilliseconds", (x) => is.integer(x) && is.positive(x));
    this.#windowMaximumCount = windowMaximumCount;
    this.#windowDurationMilliseconds = windowDurationMilliseconds;
    this.#scheduler = new import_Scheduler.default();
    this.#workQueue = new import_Queue.default();
    this.#windowStart = null;
    this.#windowCounter = 0;
  }
  /**
   * Adds an item to the work queue and returns a promise that will
   * resolve after the item completes execution.
   *
   * @public
   * @param {Function} actionToEnqueue - The action to execute.
   * @returns {Promise}
   */
  enqueue(actionToEnqueue) {
    return promise.build((resolveCallback, rejectCallback) => {
      assert.argumentIsRequired(actionToEnqueue, "actionToEnqueue", Function);
      if (this.disposed) {
        throw new Error("Unable to enqueue action, the rate limiter has been disposed.");
      }
      this.#workQueue.enqueue(async () => {
        try {
          const result = await actionToEnqueue();
          resolveCallback(result);
        } catch (error) {
          rejectCallback(error);
        } finally {
          this.#checkStart();
        }
      });
      this.#checkStart();
    });
  }
  /**
   * @protected
   * @override
   */
  _onDispose() {
    this.#scheduler.dispose();
    this.#workQueue = null;
  }
  /**
   * Returns a string representation.
   *
   * @public
   * @returns {string}
   */
  toString() {
    return "[RateLimiter]";
  }
  #checkStart() {
    if (this.disposed) {
      return;
    }
    if (this.#workQueue.empty()) {
      return;
    }
    if (this.#windowStart === null) {
      const timestamp = /* @__PURE__ */ new Date();
      this.#windowStart = timestamp.getTime();
      this.#windowCounter = 0;
      const resetWindow = () => {
        this.#windowStart = null;
        this.#windowCounter = 0;
        this.#checkStart();
      };
      this.#scheduler.schedule(resetWindow, this.#windowDurationMilliseconds, "Rate Limiter Window Reset");
    }
    if (this.#windowCounter < this.#windowMaximumCount) {
      this.#windowCounter = this.#windowCounter + 1;
      const actionToExecute = this.#workQueue.dequeue();
      actionToExecute();
    }
  }
}

{
	const cjsExports = module.exports;
	const cjsDefaultExport = cjsExports && cjsExports.__esModule ? cjsExports.default : cjsExports;

	if (cjsDefaultExport && (typeof cjsDefaultExport === 'function' || typeof cjsDefaultExport === 'object')) {
		Object.keys(cjsExports).forEach((key) => {
			if (key !== 'default' && key !== '__esModule') {
				cjsDefaultExport[key] = cjsExports[key];
			}
		});
	}

	module.exports = cjsDefaultExport;
}