effect/dist/cjs/internal/rateLimiter.js

The missing standard library for TypeScript, for writing production-grade software.

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.withCost = exports.make = void 0;
var Duration = _interopRequireWildcard(require("../Duration.js"));
var Effect = _interopRequireWildcard(require("../Effect.js"));
var FiberRef = _interopRequireWildcard(require("../FiberRef.js"));
var _Function = require("../Function.js");
var _GlobalValue = require("../GlobalValue.js");
function _getRequireWildcardCache(e) { if ("function" != typeof WeakMap) return null; var r = new WeakMap(), t = new WeakMap(); return (_getRequireWildcardCache = function (e) { return e ? t : r; })(e); }
function _interopRequireWildcard(e, r) { if (!r && e && e.__esModule) return e; if (null === e || "object" != typeof e && "function" != typeof e) return { default: e }; var t = _getRequireWildcardCache(r); if (t && t.has(e)) return t.get(e); var n = { __proto__: null }, a = Object.defineProperty && Object.getOwnPropertyDescriptor; for (var u in e) if ("default" !== u && {}.hasOwnProperty.call(e, u)) { var i = a ? Object.getOwnPropertyDescriptor(e, u) : null; i && (i.get || i.set) ? Object.defineProperty(n, u, i) : n[u] = e[u]; } return n.default = e, t && t.set(e, n), n; }
/** @internal */
const make = ({
  algorithm = "token-bucket",
  interval,
  limit
}) => {
  switch (algorithm) {
    case "fixed-window":
      {
        return fixedWindow(limit, interval);
      }
    case "token-bucket":
      {
        return tokenBucket(limit, interval);
      }
  }
};
exports.make = make;
const tokenBucket = (limit, window) => Effect.gen(function* () {
  const millisPerToken = Math.ceil(Duration.toMillis(window) / limit);
  const semaphore = yield* Effect.makeSemaphore(limit);
  const latch = yield* Effect.makeSemaphore(0);
  const refill = Effect.sleep(millisPerToken).pipe(Effect.zipRight(latch.releaseAll), Effect.zipRight(semaphore.release(1)), Effect.flatMap(free => free === limit ? Effect.void : refill));
  yield* (0, _Function.pipe)(latch.take(1), Effect.zipRight(refill), Effect.forever, Effect.forkScoped, Effect.interruptible);
  const take = Effect.uninterruptibleMask(restore => Effect.flatMap(FiberRef.get(currentCost), cost => Effect.zipRight(restore(semaphore.take(cost)), latch.release(1))));
  return effect => Effect.zipRight(take, effect);
});
const fixedWindow = (limit, window) => Effect.gen(function* () {
  const semaphore = yield* Effect.makeSemaphore(limit);
  const latch = yield* Effect.makeSemaphore(0);
  yield* (0, _Function.pipe)(latch.take(1), Effect.zipRight(Effect.sleep(window)), Effect.zipRight(latch.releaseAll), Effect.zipRight(semaphore.releaseAll), Effect.forever, Effect.forkScoped, Effect.interruptible);
  const take = Effect.uninterruptibleMask(restore => Effect.flatMap(FiberRef.get(currentCost), cost => Effect.zipRight(restore(semaphore.take(cost)), latch.release(1))));
  return effect => Effect.zipRight(take, effect);
});
/** @internal */
const currentCost = /*#__PURE__*/(0, _GlobalValue.globalValue)( /*#__PURE__*/Symbol.for("effect/RateLimiter/currentCost"), () => FiberRef.unsafeMake(1));
/** @internal */
const withCost = cost => Effect.locally(currentCost, cost);
exports.withCost = withCost;
//# sourceMappingURL=rateLimiter.js.map