Namespace Concurrent

Package: @litert/concurrentImport path: @litert/concurrentSource: packages/partials/concurrent/src/

The Concurrent namespace provides utilities for managing concurrent operations, including throttling, debouncing, rate limiting, circuit breaking, mutexes, and fiber pools.

Install

Use this namespace only:

npm i @litert/concurrent

Or install the full bundle:

npm i @litert/utils

And then import from it.

import * as LibUtils from '@litert/utils';
const mutex = new LibUtils.Concurrent.MemoryMutex();

// or
import { Concurrent as LibConcurrent } from '@litert/utils';
const mutex = new LibConcurrent.MemoryMutex();

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Errors

Symbol	Description
E_RATE_LIMITED	Thrown when a rate limiter blocks a call
E_BREAKER_OPENED	Thrown when a circuit/manual breaker is open
E_LOCK_FAILED	Thrown when a mutex lock cannot be acquired

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Typings

See Typings.md for shared interfaces used across multiple APIs.

Name	Description
ICounter	Generic counter interface used by CountingRateLimiter and CircuitBreaker.
ISimpleFn	Type for a zero-parameter function.
IBreaker	Interface implemented by all circuit breaker classes.
ISyncRateLimiter	Interface for synchronous rate limiters.
ISyncRateLimiterManager	Interface for managing per-key synchronous rate limiters.
IAsyncRateLimiter	Interface for asynchronous rate limiters.
IAsyncRateLimiterManager	Interface for managing per-key asynchronous rate limiters.

Class-specific option and event interfaces are documented on each class's page.

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Classes

Flow Control

Class	Description
ThrottleController<T>	Throttles concurrent async function calls — deduplicates in-flight calls by ID
DebounceController	Debounces a function call with optional max-delay cap
BatchBuffer<T>	Buffers items and delivers them in batches on timer or capacity

Counters & Rate Limiters

Class	Description
SlideWindowCounter	Sliding time-window counter divided into sub-windows
CountingRateLimiter	Sync rate limiter backed by any ICounter
TokenBucketRateLimiter	Sync rate limiter using the token-bucket algorithm
LeakyBucketRateLimiter	Async rate limiter using the leaky-bucket algorithm
TokenBucketRateLimiterManager	Per-key token-bucket manager
LeakyBucketRateLimiterManager	Per-key leaky-bucket manager

Synchronization

Class	Description
MemoryMutex	In-memory mutex with optional reentrant support
FiberPool	Pool of FiberController workers for concurrent task execution

Circuit Breakers

Class	Description
ManualBreaker	Manually controlled circuit breaker
CircuitBreaker	Automatic circuit breaker with half-open recovery