Limiter

A promise pool with RPS limiter.

Features:

• TypeScript first
• Limits parrallel promises execution
• Limits RPS (requests per second), evenly distributes the requests over time
• Able to retry
• Simple API
• Simple async/await flow
• Allows to handle errors silently using onError callback
• Works with any runtime (Bun/Deno/Node)

Install

bun add github:nesterow/limiter # or pnpm

Usage

Limit number of requests

import {Limiter} from '@nesterow/limiter'

const task = () => {
    await fetch('https://my.api.xyz')
    // ... write
}

const limiter = new Limiter({
    limit: 10
})

for (let i=0; i<100; i++) {
    await limiter.process(task)
}

Limit RPS

import {Limiter} from '@nesterow/limiter'

const execEvery100ms = () => {
    await fetch('https://my.api.xyz')
    // ... write
}

const limiter = new Limiter({
    limit: 20
    rps: 10
})

for (let i=0; i < 100; i++) {
    await limiter.process(execEvery100ms)
}

Retry

import {Limiter, LimiterRetryError} from '@nesterow/limiter'

const retry5times = () => {
    await fetch('https://my.api.xyz')
    throw new Error("Connection refused")
    // ... write
}

const limiter = new Limiter({
    limit: 20
    maxRetry: 5
})

for (let i=0; i < 100; i++) {
    try {
        await limiter.process(retry5times)
    } catch(e) {
        if (e instanceof LimiterRetryError) {
            // Logger.log(e)
        }
    }
}

Handle errors in background

import {Limiter, LimiterRetryError} from '@nesterow/limiter'

const wontStopPooling = () => {
    await fetch('https://my.api.xyz')
    throw new Error("Connection refused")
    // ... write
}

const limiter = new Limiter({
    limit: 20
    maxRetry: 5,
    onError(error) {
        // Logger.error(error)
    }
})

for (let i=0; i < 100; i++) {
    await limiter.process(wontStopPooling)
}