| 28 | } |
| 29 | |
| 30 | const tokenBucket = (limit: number, window: DurationInput): Effect.Effect< |
| 31 | RateLimiter.RateLimiter, |
| 32 | never, |
| 33 | Scope.Scope |
| 34 | > => |
| 35 | Effect.gen(function*() { |
| 36 | const millisPerToken = Math.ceil(Duration.toMillis(window) / limit) |
| 37 | const semaphore = yield* Effect.makeSemaphore(limit) |
| 38 | const latch = yield* Effect.makeSemaphore(0) |
| 39 | const refill: Effect.Effect<void> = Effect.sleep(millisPerToken).pipe( |
| 40 | Effect.zipRight(latch.releaseAll), |
| 41 | Effect.zipRight(semaphore.release(1)), |
| 42 | Effect.flatMap((free) => free === limit ? Effect.void : refill) |
| 43 | ) |
| 44 | yield* pipe( |
| 45 | latch.take(1), |
| 46 | Effect.zipRight(refill), |
| 47 | Effect.forever, |
| 48 | Effect.forkScoped, |
| 49 | Effect.interruptible |
| 50 | ) |
| 51 | const take = Effect.uninterruptibleMask((restore) => |
| 52 | Effect.flatMap( |
| 53 | FiberRef.get(currentCost), |
| 54 | (cost) => Effect.zipRight(restore(semaphore.take(cost)), latch.release(1)) |
| 55 | ) |
| 56 | ) |
| 57 | return (effect) => Effect.zipRight(take, effect) |
| 58 | }) |
| 59 | |
| 60 | const fixedWindow = (limit: number, window: DurationInput): Effect.Effect< |
| 61 | RateLimiter.RateLimiter, |